WO2010027109A1

WO2010027109A1 - Endoscope system, method of using the same, assisting tool and adapter

Info

Publication number: WO2010027109A1
Application number: PCT/JP2009/065975
Authority: WO
Inventors: Yuichi Torii; Haruhiko Arai; Takehiko Koga; Toshiyuki Ikeda; Masaya Inoue; Masahiro Seki; Tomoharu Nishino; Shozo Iyama
Original assignee: Fujifilm Corporation
Priority date: 2008-09-08
Filing date: 2009-09-07
Publication date: 2010-03-11
Also published as: KR20110066137A; CN102149312A; EP2339950A1; EP2339950A4; KR101644842B1; CN102149312B

Abstract

An assisting tool (12) combined with a nasal endoscope (11) is provided. The assisting tool (12) has an insertion section (35) insertable through the other nostril as the endoscope (11). The assisting tool (12) has an attachment portion (36) attachable to a forceps inlet port (19) of the endoscope (11). The attachment portion (36) includes a forceps inlet port (42) and a bifurcated connecting channel for connecting the forceps inlet port (42) to both forceps channels in the assisting tool (12) and the endoscope (11). The insertion sections (16, 35) have fastening members (23, 24, 40, 41) to fasten these insertion sections together. The insertion sections (16, 35) are inserted through different nostrils and fastened together with the fastening members (23, 24, 40, 41), as their front faces are aligned in the area around the posterior nares, and then advanced together from the esophagus to the stomach.

Description

DESCRIPTION

ENDOSCOPE SYSTEM, . METHOD OF USING THE SAME, ASSISTING TOOL AND ADAPTER

Technical Field

The present invention relates to an endoscope system for visualizing the interior of a patient's body, a method of using the same, and an assisting tool and an adapter to be used with this endoscope system.

Background Art

A nasal endoscope is the device having a flexible and tubular insertion section to be inserted through a nostril for visualizing the interior of a patient's body (see, for example, Japanese Patent Laid-open Publications No. 2006-68030 and No. 2007-61377). Because of this insertion section that can enter into esophagus without touching a tongue root, the nasal endoscope puts less physical burden on the patients, inducing less gag reflex and less nausea than oral endoscopes whose insertion section is inserted through a patient's mouth. Having additional advantages in that it requires less anesthetic than the oral endoscopes, and that it allows the patient under examination to have a conversation, and that it allows the patient to take breaths through the mouth, the nasal endoscope is now in increasing demand.

The nasal endoscope is almost identical in configuration to the oral endoscope, and incorporates an observation optical system and an illumination optical system in a distal portion of the insertion section. The insertion section also has an interior space throughout the length. This interior space holds various lengthy components, including a forceps channel for inserting a medical instrument, an air/water feed tube for delivering air and water to a front face of the observation optical system (i.e., observation window) or inside the body cavity, and a light guide for guiding illumination light from a light source device to the illumination optical system so as to cast the illumination light from the distal portion.

To facilitate inserting and advancing in a narrow and tortuous path between the nostril and the middle (or inferior) meatus, the insertion section of the nasal endoscope is narrower, typically 6 mm, in diameter than that of the oral endoscope which is typically 9 mm in diameter. Certainly, the insertion section of the nasal endoscope cannot provide sufficient interior space as the oral endoscope does, and thus the forceps channel and other lengthy components need to be ever narrower or at least one of them has to be removed. Narrowing of the forceps channel results in limiting the size of the medical instrument being used, and reduces the amount of biopsies being obtained in medical examination. The forceps channel also functions as a suction tube for suctioning the residual air, the residual liquid and body fluid from a patient' s body cavity. Therefore, with the narrower forceps channel, the suction amount decreases and the suction time increases. With the narrower air/water feed tube, the air or water flow rate per unit time decreases. Therefore, it takes a long time to dilate the stomach for view expansion or to wash out blood and mucus that hinder the observation. With the narrower light guide, the intensity of the illumination light is insufficient to illuminate a distant area.

As described, the nasal endoscope is advantageous for reducing the physical burden on the patient, but at the same time disadvantageous in that it has more functional restrictions than the oral endoscope. Therefore, in the case that the lesion or wound is difficult to treat with the nasal endoscope, the nasal endoscope has to be replaced with the oral endoscope during the diagnostic examination.

In view of the forgoing, it is an object of the present invention to enable the medical procedure and treatment that have been considered difficult to perform due to structural and functional limitations caused by miniaturization of the insertion section.

Disclosure of Invention In order to achieve the above objects and other objects, the endoscope system according to the present invention includes an endoscope having a primary insertion section to be inserted into a body cavity through a nostril, and an assisting tool used together with the endoscope. This assisting tool has an auxiliary insertion section to be inserted into the body cavity through the other nostril for the purpose of assisting function of the endoscope.

The assisting tool may preferably assist the function of at least one of a forceps channel, an illuminator, an air feed channel and a water feed channel of the endoscope.

The assisting tool preferably has an auxiliary forceps channel that extends between proximal and distal ends of the auxiliary insertion section.

A proximal end of the assisting tool is preferably provided with an attachment detachably attached to an endoscope operation section that is coupled to a proximal end of the primary insertion section.

Preferably, the endoscope has a primary forceps channel and a primary forceps inlet port exposed on the operation section. The primary forceps channel extends between distal and proximal ends of the primary insertion section. The primary forceps inlet port is coupled to the primary forceps channel. In this case, the attachment of the assisting tool is provided with an auxiliary forceps inlet port coupled to the auxiliary forceps channel, and a connecting channel for connecting the auxiliary forceps channel and the primary forceps inlet port. It is preferred that the endoscope system further includes a fastening member on either one or both of the primary and auxiliary insertion sections. This fastening member is configured to fasten front ends of the primary and auxiliary insertion sections in a detachable manner, so as to orient front faces of the primary and auxiliary insertion sections in the same direction.

The auxiliary insertion section may have an illuminator for assisting an illumination function of the endoscope. In this case, the endoscope system preferably includes a processing device connected to the endoscope, and a light source device connected to both the processing device and the assisting tool. The processing device generates a video signal and brightness information based on an image signal from an image sensor of the endoscope. The light source device has a light source capable of changing luminous intensity based on the brightness information. The illuminator of the assisting tool, in this case, includes a light guide, an illumination lens and an illumination window. The light guide passes through an interior space extending between the distal and proximal ends of the auxiliary insertion section, and conveys illumination light from the light source to the proximal end. The illumination lens is adjacent to a light exit end of this light guide. The illumination window is configured to emit the illumination light having passed through the illumination lens into the body cavity. Preferably, the endoscope system may further include an LED controller connected to the assisting tool. In this case, the illuminator of the assisting tool includes at least one white LED whose luminous intensity is adjustable by the LED controller, and an illumination window for emitting the light of this white LED into the body cavity.

Also, in this case, the endoscope system may further include a processor connected to both the endoscope and the LED controller.

This processor generates a video signal and brightness information based on an image signal generated by an image sensor of said endoscope, and transmits the brightness information to the LED controller. In response, the LED controller adjusts luminous intensity of the LED based on the brightness information.

It is also preferred to provide the endoscope system with a light guide and an auxiliary LG socket. This light guide passes through an interior space extending between distal and proximal ends of the primary insertion section, and has a light entrance end and a light exit ends. The auxiliary LG socket is connected to a part of the light exit end of the light guide. In this case, the assisting tool is provided with an LG attachment on the proximal end. This LG attachment has an auxiliary LG connector coupled to a light entrance end of the assisting tool's light guide. Detachably attaching the auxiliary LG connector to the auxiliary

LG socket, the LG attachment allows illumination light in the endoscope's light guide to enter the assisting tool's light guide .

It is further preferred that the endoscope system includes a magnet in a front end of one of the primary and auxiliary insertion sections, and a magnetically attractable body in a front end of the other insertion sections. Attracted to the magnet, the magnetically attractable body fastens these insertion sections together while aligning their front faces. At least one of the magnet and the magnetic body is preferably elongated in an axial direction of corresponding insertion section. This elongated shape allows each of the primary and auxiliary insertion sections to move relatively in the axial direction without separating from each other. In this case, the auxiliary insertion section and the primary insertion section are provided with an engaging member and an engaged member in their front ends respectively. These members mechanically fasten the front ends of the primary and auxiliary insertion sections together. The engaging member is configured to engage with the engaged member as the auxiliary insertion section moves in the axial direction on the primary insertion section. It is preferred in this case that the engaging member and the engaged member align the front faces of the primary and auxiliary insertion sections as they engage with each other to fasten the front ends together. The magnet is preferably an electromagnet . Further, the endoscope system preferably includes a detector for detecting the fastening of the primary and auxiliary insertion sections.

The endoscope system may also include a tubular guide member attached parallel to the auxiliary insertion section. This guide member is configured to permit passage of the primary insertion section and hold the primary insertion section along the auxiliary insertion section.

An outer surface of this guide member is preferably formed with at least one access window portion for permitting passage of the primary insertion section.

This window portion is preferably composed of a through hole on the outer surface of the guide member, and a guide element for guiding the primary insertion section approaching from a proximal end of the guide member to this through hole. The endoscope system may further include an adapter for connecting a proximal end of the auxiliary insertion section and a handling part of the endoscope. This adapter preferably includes an endoscope mount attachable to the handling part of the endoscope, and an assisting tool mount attachable to the proximal end of the assisting tool.

The endoscope mount preferably has an endoscope port. This endoscope port is configured to fit to a primary forceps inlet port that is coupled to a primary forceps channel passing through an interior space extending from a distal end of the primary insertion section to the handling part of the endoscope. Also, the assisting tool mount preferably has an assisting tool port. This assisting tool port is configured to fit to an auxiliary forceps inlet port that is coupled to an auxiliary forceps channel passing through an interior space between distal and proximal ends of the auxiliary insertion section. In this case, the adapter has a single or pair of adapter-side forceps inlet ports. The single adapter-side forceps inlet port is connected in parallel to both the endoscope port and the assisting tool port. The pair of adapter-side forceps inlet ports are separately connected to the one of the endoscope port and said assisting tool port.

More preferably, the assisting tool includes a suction channel, a suction valve and a port. The suction channel passes through an interior space between a suction mouth on a front face of the auxiliary insertion section and a proximal end of the auxiliary insertion section. The suction valve is placed on the proximal end, and opens and closes the suction channel. The port connects a suction device to the suction channel as the suction valve opens for suctioning. Preferably, the suction channel also functions as a forceps channel.

A method of using an endoscope system according to the present invention includes a first inserting step, a second inserting step, a fastening step and an attaching step. This endoscope system includes an endoscope and an assisting tool for assisting function of the endoscope. In the first inserting step, a primary insertion section of the endoscope is inserted through a nostril. The primary insertion section has an image sensor on its distal end and at least a primary forceps channel passing through an interior space between the distal and proximal ends of the primary insertion section. In the second inserting step, an auxiliary insertion section of the assisting tool is inserted through the other nostril. The auxiliary insertion section has an auxiliary forceps channel that has a larger diameter than the primary forceps channel and extends between distal and proximal ends of the auxiliary insertion section. In the fastening step, the primary and auxiliary insertion sections are detachably fastened together on their front ends while their front faces are aligned, within an area between posterior nasal aperture and esophagus, using a fastening member provided in one of the front ends of the assisting tool and the endoscope. In the attaching step, the proximal end of the auxiliary insertion section is detachably attached to a handling part of the endoscope before or after the second insertion step or after the fastening step. The handling part is coupled to the proximal end of the primary insertion section.

An assisting tool according to the present invention is used together with an endoscope having a primary insertion section to be inserted into a body cavity through a nostril, and includes an auxiliary insertion section to be inserted into the body cavity through the other nostril so as to assist function of the endoscope.

Additionally, the assisting tool preferably includes a fastening member for detachably fastening front ends of the primary and auxiliary insertion sections together with their front faces being aligned.

This fastening member preferably includes an annular retainer for permitting passage of the primary insertion section so as to fasten the insertion sections together.

The retainer may be a ring-shaped or sleeve-shaped balloon that can expand upon inflation of fluid and shrink upon suction of the fluid. This balloon changes its inner diameter upon expansion and shrinkage, and holds or releases the primary insertion section.

Alternatively, the retainer may be a loop of string translatable between a retracted position into a restraint channel that passes through the auxiliary insertion section and a projected position out of the restraint channel. This loop of string changes its projection length from the restraint channel, and holds or releases the primary insertion section.

The said loop of string is preferably made from an elastic wire that is previously shaped to expand to a loop upon projecting from the restraint channel.

An adapter according to the present invention includes an endoscope mount and an assisting tool mount, and connects an endoscope having a long slender primary insertion section to be inserted into a body cavity through a nostril and an assisting tool having a long slender auxiliary insertion section to be inserted into said body cavity through the other nostril so as to assist function of said endoscope. The endoscope mount is attachable to a handling part coupled to a proximal end of the primary insertion section. The assisting tool mount is attachable to a proximal end of the auxiliary insertion section.

According to the present invention, there is provided an assisting tool to offer supplemental functions for the nasal endoscope. This assisting tool enables the medical procedure and treatment that have been considered difficult to perform with the nasal endoscope.

Brief Description of Drawings Figure 1 is a perspective view of an endoscope system according to the present invention;

Figure 2 is a cross sectional view of an insertion section of the endoscope; Figure 3 is a front view of the insertion section;

Figure 4 is an axial cross sectional view of a distal portion of the endoscope;

Figure 5 is a cross sectional view of an insertion section of an assisting tool; Figure 6 is an axial cross sectional view around a leading end of the assisting tool;

Figure 7 is an explanatory view illustrating the endoscope and the assisting tool tied together at their front parts;

Figure 8 is an explanatory view illustrating the connection of an endoscope system;

Figure 9 is an explanatory view illustrating the situation before pressing an air/water feed button;

Figure 10 is an explanatory view illustrating the situation upon pressing an air/water feed button; Figure 11 is an explanatory view of a suction device and a universal connector linked thereto;

Figure 12 is a flow chart of medical examination using the endoscope system;

Figure 13 is an explanatory view illustrating the insertion section inserted through a nostril;

Figure 14 is an explanatory view illustrating one example of the assisting tool for providing a sucking function;

Figure 15 is an explanatory view illustrating one example of the assisting tool for providing a water jet function; Figure 16 is a perspective view of a second embodiment endoscope system which has an assisting tool for providing an illumination function; Figure 17 is a cross sectional view of the assisting tool containing a light guide;

Figure 18 is an axial cross sectional view around a leading end of the assisting tool with the light guide; Figure 19 is an explanatory view illustrating the connection of the second embodiment endoscope system;

Figure 20 is a perspective view of a light source device;

Figure 21 is a front view of an operation panel of the light source device; Figure 22 is a flow chart of medical examination using the second embodiment endoscope system;

Figure 23 is an explanatory view illustrating the assisting tool connected to the light guide of the endoscope;

Figure 24 is an explanatory view illustrating a light source device having two separate light sources for the endoscope and the assisting tool;

Figure 25 is an explanatory view illustrating two separate light source devices for the endoscope and the assisting tool;

Figure 26 is an explanatory view illustrating an assisting tool for providing LED illumination;

Figure 27 is an explanatory view illustrating an assisting tool having an illumination function and a forceps channel;

Figure 28 is a front view of the assisting tool having the illumination function and the forceps channel; Figure 29 is a front view of an assisting tool having a plurality of LEDs;

Figure 30 is an explanatory view illustrating an assisting tool for providing the illumination function and a water jet function; Figure 31 is a perspective view of a third embodiment endoscope system in which an assisting tool is fastened to an endoscope at their front parts; Figure 32 is an explanatory view illustrating the configuration of the front part of an insertion section of the assisting tool;

Figure 33 is an explanatory view illustrating the configuration of the front part of an insertion section of the endoscope;

Figures 34A and 34B are explanatory views illustrating the front part of the assisting tool being fastened to the front part of the endoscope; Figure 35 is an explanatory view illustrating the front part of a fourth embodiment endoscope having magnets to fasten the assisting tool;

Figure 36 is an explanatory view illustrating the front part of the assisting tool to be fastened by the magnets; Figures 37A and 37B are explanatory views illustrating the front part of the assisting tool being fastened to the front part of the endoscope by the magnets;

Figure 38 is a perspective view of a fifth embodiment endoscope system in which an assisting tool has a fastening tool; Figure 39 is a cross sectional view of the assisting tool having an annular balloon as the fastening tool;

Figure 40 is an explanatory view schematically illustrating an air feed path fitted in the balloon;

Figures 4 IA to 41C are explanatory views illustrating the front part of the assisting tool being fastened to the front part of the endoscope by the balloon;

Figures 42A and 42B are explanatory views of the assisting tool having a tubular balloon as the fastening tool;

Figure 43 is an explanatory view illustrating the assisting tool having a binding loop of elastic wire as the fastening tool;

Figure 44 is a perspective view of a sixth embodiment endoscope system in which an assisting tool has a guide member; Figure 45 is an explanatory view illustrating an insertion opening on the guide member;

Figures 46A to 46C are explanatory views illustrating the endoscope being inserted into the guide member; Figure 47 is an axial cross' sectional view around leading ends of the assisting tool and the guide member;

Figure 48 is a cross sectional view of an assisting tool' s flexible section and the guide member;

Figure 49 is a front view of the assisting tool's flexible section and the guide member;

Figure 50 is a cross sectional view of the assisting tool and the folded guide member;

Figure 51 is a perspective view of a seventh embodiment endoscope system having an adapter; Figure 52 is a horizontal cross sectional view of the adapter;

Figure 53 is a perspective view of the adapter;

Figure 54 is a perspective view of an adapter having a pair of insertion ports for separately connecting to forceps channels of the endoscope and the assisting tool;

Figure 55 is a perspective view of a eighth embodiment endoscope system in which an assisting tool has a suction bulb;

Figure 56 is an explanatory view illustrating the connection of the seventh embodiment endoscope system; Figure 57 is a cross sectional view of the suction bulb in a bulb-close state;

Figure 58 is a cross sectional view of the suction bulb in a bulb-open state;

Figure 59 is a flow chart of medical procedure using the seventh embodiment endoscope system;

Figure 60 is a perspective view of a variation of the eighth embodiment endoscope system in which an assisting tool is attached to an endoscope through an engaging mechanism; and

Figure 61 is an explanatory view illustrating an assisting tool for providing a sucking function and an illumination function.

Best Mode for Carrying Out the Invention [First Embodiment]

Referring to FIG. 1, an endoscope system 10 includes a nasal endoscope (hereinafter, endoscope) 11, an assisting tool 12, a light source device 13, a processing device 14 and a monitor 15. The endoscope 11 has an insertion section 16 to be inserted through one of external nares of a patient. The insertion section 16 is connected to an operation section 17 by way of a grip portion 22a. The operation section 17 is linked to a universal cable 18a. At a leading end of the universal cable 18a, there is provided a universal connector 18 to connect the endoscope 11 with the light source device 13 and the processing device 14.

The insertion section 16 is hollow substantially throughout the length, and contains a forceps channel. This forceps channel is connected at one end to a forceps outlet port on a front of the insertion section 16, and at the other end to a forceps inlet port 19 on the grip portion 22a. The forceps inlet port 19 may be formed on the operation section 17. The grip portion 22a and the operation section 17 constitute a handling part. As is known, the insertion section 16 includes a distal portion 20, a bending portion 21 and a flexible portion 22. In front and in the rear of the bending portion 21, magnets 23, 24 are positioned. The distal portion 20 and the bending portion 21 constitute a front part of the insertion section 16. The distal portion 20 has a rigid metal body that holds an observation optical system and an illumination optical system. The universal connector 18 is composed of a light guide connector (LG connector) 25 and an electric connector 26 extending from the LG connector 25. The LG connector 25 is connected to the light source device 13, and the electric connector 26 is connected to the processing device 14. The processing device 14 has a power circuit and an image processing circuit for encoding an image signal of an image sensor into a composite signal or an RGB component signal. The light source device 13 has a light source lamp, and the irradiated light is transmitted to the illumination optical system by a light guide (fiber bundle) that extends through the operation section 17, the grip portion 22a and the internal space of the insertion section 16.

The flexible portion 22 connects the handling part and the bending portion 21. The flexible portion 22 is a long and slender tubular member with flexibility. The bending portion 21 is bent up, down, right and left by angle wires that run through the interior space of the insertion section 16 and are pushed and pulled upon operation of an angle knob 28 on the operation section 17. This bending action leads to orient a front face of the distal portion 20 toward an affected part, or namely the area of lesion in the patient' s body. The affected part is irradiated by the light from the illumination optical system, and the reflected light is captured through the observation optical system by the image sensor. The image signal of the image sensor is then processed appropriately, and the image of the affected part is displayed on the monitor 15.

In addition to the angle knob 28 and the forceps inlet port 19, the operation section 17 is provided with an air/water feed button 30, a suction button 31 and a water-jet (WJ) port 32. The WJ port 32 is detachably connected to a syringe or a water supply device that holds rinse water, medical solution or other fluid to be sprayed on the affected part. Normally, the WJ port 32 and the forceps inlet port 19 are closed with detachable stoppers.

The assisting tool 12 is used with the endoscope 11, and composed of an insertion section 35 and an attachment portion 36.

The insertion section 35 is inserted through the other unoccupied one of the external nares. The attachment portion 36 is connected to a proximal end of the insertion section 35, and attached detachably to the handling part of the endoscope 11. The insertion section 35 is composed of a distal portion 37, a bending portion

38 and a flexible portion 39. The assisting tool 12 has a pair of tubular magnets 40, 41 aligned along an insertion direction in the bending portion 38. These magnets 40, 41 catch a pair of the magnets 23, 24 of the endoscope 11 as they are advanced to around the inferior meatus and the esophagus. In this condition, the bending portion 38 of the assisting tool 12 follows the bending action of the bending portion 21 of the endoscope 11, and a front face of the distal portion 37 of the assisting tool 12 is oriented to the same direction as the front face of the distal portion 20 of the endoscope 11. The distal portion 37 of the assisting tool 12 is made of a rigid material. The bending portion 38 can bend together with the bending portion 21 of the endoscope 11. The flexible portion

39 connects the attachment portion 36 and the bending portion 38. The flexible portion 39 is a long and slender tubular member with flexibility.

The insertion section 35 has a forceps channel 72 (see, FIG. 5) that passes completely through to the attachment portion 36. This forceps channel 72 is connected at the one end to a forceps outlet port formed on the front face of the assisting tool 12, and at the other end to a forceps inlet port 42 formed in the attachment portion 36. A forceps channel stopper 42a is attached to the forceps inlet port 42. The forceps channel stopper 42a has an elastic cork with a slit or a small aperture to be push-opened by a medical instrument, and closes the forceps inlet port 42 to prevent the impure solution in the patient's body from flowing out of the forceps inlet port 42 by way of the forceps channel 72.

The attachment portion 36 is attached to the forceps inlet port 19 on the grip portion 22a. The attachment portion 36 has a connecting channel for connecting the forceps channel 72 to the forceps inlet port 19 as it is attached to the forceps inlet port 19. This connecting channel provides options of the forceps channels. A forceps or such a medical instrument is inserted through the forceps inlet port 42, and then directed to one of the forceps channels in the endoscope 11 and the assisting tool 12. The insertion sections 16, 35 are both made into slender flexible tubes to facilitate the insertion from the nostril to the stomach or the duodenum via the inferior meatus and the esophagus, and have almost the same diameter and length. In the medical examination using the endoscope 11, the attachment portion 36 of the assisting tool 12 can be attached to the grip portion 22a either before or after the insertion of the insertion sections 16, 35 into the patient's body. For better workability in the latter situation, the insertion section 35 of the assisting tool 12 preferably is preferably made longer than the insertion section 16 of the endoscope 11. Also, in view of the situation where the insertion section 16 of the endoscope 11 is found too wide to insert into one of the nostrils in an endoscope inserting test, the insertion section 35 is preferably made thinner than the insertion section 16. As shown in FIG, 2, the flexible portion 22 is configured by a three-layered flexible tube 47 composed of a flexible spiral tube 44, so-called a flex, for internal protection, a net 45, so-called a blade, being coated on the spiral tube 44 to retain a protective layer 46, and the resin-made protective layer 46 coated on the net 45.

The flexible portion 22 loosely holds a plurality of lengthy contents, including a pair of light guides 48, 49 for delivering the illumination light to an illumination lens in the distal portion 20, angle wires 50, a forceps channel 51, an air/water feed channel 52, a multicore cable 53 and a water-jet (WJ) channel 54. The multicore cable 53, which is composed of a plurality of signal wires and a protective tube for binding these signal lines, transmits a drive signal from an image signal processing section to an image sensor, and also transmits an image signal of the image sensor back to the image signal processing section. The angle wires 50 are actually an up-down angle wire and a right-left angle wire wound around separate pulleys, while their terminal ends being fastened to the bending portion 21. When viewed in cross section, there are four angle wires 50 within the flexible portion

22, and each angle wire 50 is inserted into a tight coil pipe 50a.

As shown in FIG.3, the distal portion 20 of the endoscope 11 has a front face 20a that exposes an observation window 55, a pair of illumination windows 56, 57, a water-jet (WJ) nozzle 58, a forceps outlet port 59 and an air/water nozzle 60. The observation window 55 exposes a part of an objective optical system 61 (see, FIG. 4) that receives an image light of the region of interest in the patient's body. The illumination windows 56, 57 are positioned on both sides of the observation window 55, and irradiate the region of interest with the illumination light that is transmitted from the light source device 13 through the light guides 48, 49. The forceps outlet port 59 of the endoscope 11 is connected to the forceps inlet port 19 via the forceps channel 51. The air/water nozzle 60 discharges air and water to an affected part or sprays rinse water and air onto the observation window 55, according to the operation of the air/water feed button 30 on the operation section 17. The WJ nozzle 58 discharges rinse water or various types of medical solution, supplied from a syringe attached to the WJ port 32, toward the region of interest.

As shown in FIG. 4, the objective optical system 61 is partially exposed from the observation window 55. The illumination light out of the illumination windows 56, 57 is reflected on the region of interest, and enters the objective optical system 61. This incident light, or object light, passes through the objective optical system 61 and enters a prism 62. The object light is then bent in the prism 62, and focused onto an imaging surface of an image sensor 63. The image sensor 63 is coupled to a circuit board 64 that is connected to each signal wire 53a of the multicore cable 53.

The distal portion 20 and the bending portion 21 are covered with a flexible angle rubber 65. Placed inside the angle rubber 65 is a front-side connection ring 66 that holds the terminal ends of the angle wires 50. The front-side connection ring 66 is connected to the plurality of joint pieces interconnected alternately with a pair of right and left pins or upper and lower pins to extend toward the proximal end. The up-down angle wire 50 and the right-left angle wire 50 are translatably supported on the inner walls of the joint pieces, and pushing and pulling of the angle wires 50 leads to bend these joint pieces in the vertical or horizontal directions.

The forceps channel 51 running through the flexible portion 22 terminates in the bending portion 21. The forceps channel 51 is a synthetic resin-made flexible tube. The leading end of the forceps channel 51 is connected to a rigid pipe 67 extending in the distal portion 20. The rigid pipe 67 is connected to the forceps outlet port 59. As shown in FIG. 5, the flexible portion 39 is configured by a three-layered flexible tube 71 composed of a spiral tube 68, a net 69 and a protective layer 70, as with the flexible portion 22 of the endoscope 11. The spiral tube 68 covers the forceps channel 72 to protect it without losing the flexibility. The net 69 is coated on the spiral tube 68, and retains a protective layer 70. The protective layer 70 is made of resin coated on the net 69.

The forceps channel 72 is a synthetic resin-made flexible tube. This flexible tube has an inner diameter that is at least 70% of the outer diameter of the insertion section 35 of the assisting tool 12 and is at least twice as large as the inner diameter of the forceps channel 51 of the endoscope 11. With this dimension of the inner diameter, the forceps channel 72 of the assisting tool 12 can accept a large medical instrument.

As shown in FIG. 6, the distal portion 37 of the assisting tool 12 is covered with an end body 73. The distal portion 37 has a front face 37a that exposes a forceps outlet port 76. The forceps outlet port 76 is coupled to a rigid pipe 75, which is connected to the flexible forceps channel 72. These forceps outlet port 76, rigid pipe 75 and forceps channel 72 have substantially the same inner diameters .

The bending portion 38 of the assisting tool 12 is covered with a protective tube 74 flexible enough to bend along with the bending portion 21 of the endoscope 11. While having substantially the same structure as the flexible portion 39, the protective tube 74 of the bending portion 38 can stretch slightly in the insertion direction so as to prevent the front face 37a of the distal portion 37 from getting out of alignment with the front face 20a of the endoscope 11 as the bending portion 38 bends in accordance with the bending action of the bending portion 21 of the endoscope 11.

As shown in FIG. 7, the magnets 40, 41 in the bending portion 38 of the assisting tool 12 are fitted into grooves 77, 78 of the protective tube 74 to offer a smooth surface of the assisting tool 12. Similarly, the magnets 23, 24 in the bending portion 21 of the endoscope 11 are also fitted into grooves 79, 80 to offer a smooth surface of the endoscope 11. Being spaced at the same interval, the magnets 23, 24 and the magnets 40, 41 attract each other to tie the bending portions 21, 38 of the endoscope 11 and the assisting tool 12 horizontally at two separate points while aligning the front surfaces 20a, 37a. As shown in FIG. 8, the endoscope 11 has the image sensor 64 in the distal portion 20, and also has a CPU 83, a reference clock generator 84, a timing generator (TG) 85 and an analog front-end processor (AFE) 86 in the universal connector 18.

The image sensor 63 may be any conventional image sensor, such as a CCD or a CMOS, and captures the object light focused on the imaging surface through the objective optical system 61.

The image sensor 63 has a color filter with plural color segments

(for example, Bayer primary color filter) on this imaging surface.

The CPU 83 controls the operation of the endoscope 11. The TG 85 generates a drive pulse (vertical/horizontal drive pulse) for the image sensor 63 and a synchronization pulse for the AFE 86, in response to a reference clock signal from the reference clock generator 84, and enters these pulses into the image sensor 63 and the AFE 86. The image sensor 63 captures an image in accordance with the drive pulse from the TG 85, and transmits the image signal to the AFE 86.

The AFE 86 includes a correlation double sampling circuit (CDS) 88, an automatic gain control circuit (AGC) 89 and an analog to digital converter (A/D) 90. The CDS 88 applies a correlation double sampling process to the image signal out of the image sensor 63, and removes reset noises and amplification noises from the image signal. The AGC 89 amplifies this cleaned image signal. The A/D 90 converts this amplified image signal into a digital signal having a predetermined number of bits, and sends this digital signal to the processing device 14 via the universal connector 18. The TG 85 generates a horizontal synchronizing signal, a vertical synchronizing signal and a clock signal each corresponding to the image signal from the AFE 86, and sends these signals to the processing device 14 via the universal connector 18. The processing device 14 includes a CPU 91, an isolation circuit (insulating circuit) 92, a digital signal processing circuit (DSP) 93, a synchronization signal generating circuit (SSG) 94 and a digital to analog converter (D/A) 95.

The CPU 91 controls the operation of the processing device 14 and the light source device 13. The isolation circuit 92 isolates and insulates the endoscope 11 from the processing device 14. The DSP 93 processes the image signal to generate a video signal.

The SSG 94 generates a corrected horizontal synchronizing signal, a corrected vertical synchronizing signal and a corrected clock signal. The D/A 95 converts the video signal out of the DSP 93 into an analog video signal in, for example, NTSC format.

The horizontal synchronizing signal, the vertical synchronizing signal and the clock signal that the TG 85 of the endoscope 11 generates are entered into the SSG 94 by way of the isolation circuit 92. The SSG 94 corrects the phase shift between the horizontal synchronizing signal, the vertical synchronizing signal and the clock signal, and enters the phase-corrected signals into the DSP 93. The DSP 93 also receives the image signal from the AFE 86 of the endoscope 11 by way of the isolation circuit 92. The DSP 93 applies various types of signal processing to the image signal, including color separation, color interpolation, gain correction, white balance adjustment, gamma correction and image enhancement, so as to generate Y/C video signal composed of a luminous (Y) signal and a chroma (C) signal, and enters this Y/C signal into the D/A 95. The D/A 95 converts the entered video signal into an NTSC video signal, and sends it to the external monitor 15 connected to a connector 96.

The light source device 13 includes a light source lamp 97, a light source driver 98, an aperture stop mechanism 99, a collecting lens 100 and a CPU 101. The light source lamp 97 may be any conventional white light source, such as a xenon lamp or a halogen lamp. The light source driver 98 activates the light source lamp 97. The aperture stop mechanism 99 is positioned between the light source lamp 97 and the light guides 48, 49, and adjusts the amount of light incident to the light guides 48, 49. The collecting lens 100 collects the light passed through the aperture stop mechanism 99, and directs it to the entrance of the light guides 48, 49. The CPU 101 communicates with the CPU 91 of the processing device 14, and controls the operation of the light source driver 98 and the aperture stop mechanism 99. The light out of the light source lamp 97 passes through the aperture stop mechanism 99 and the collecting lens 100, and enters the light guides 48, 49. The light is then carried to the exit of the light guides 48, 49, and emitted from the illumination windows 56, 57 to the inside the patient's body through the illumination lenses 102, 103.

The air/water feed channel 52 coupled to the air/water nozzle 60 is divided at the rear end into an air channel 104 and a water channel 105. These air channel 104 and water channel 105 are separately connected to the air/water feed button 30. As shown in detail in FIG. 9, the air/water feed button 30 is composed of an air feed port 106, a water feed port 107, a water supply port 108 and an air supply port 109 to provide a channel switching function. The water channel 105 is connected to the water feed port 107, and the air channel 104 is connected to the air feed port 106. The water supply port 108 is coupled through a water feed connector 110 of the universal connector 18 to a water tank 111. The air supply port 109 is coupled through the universal connector 18 to a valve 112 and an air feed pump 113 in the light source device 13.

The light source device 13 is provided with an air feed button 114 for selecting air feeding pressure. The information of the air feeding pressure selected with the air feed button 114 is transmitted to the CPU 101. Based on this information, the CPU 101 controls the valve 112. The air/water feed button 30 has a through hole 115 in the middle, and the air feed pump 113 is activated all the time to expel air from the through hole 115. By closing the through hole 115 of the air/water feed button 30, the air is directed to the air/water nozzle 60, and discharged from it .

Additionally, by pressing the air/water feed button 30, as shown in FIG. 10, the air supply port 109 is closed, and the air flows into the water tank 111. This air flow pushes the water in the water tank 111 to air/water feed channel 52 by way of the water feed port 107 and the water supply port 108, and the water is discharged from the air/water nozzle 60. Referring back to FIG. 8, the WJ channel 54 in the insertion section 16 of the endoscope 11 is connected at one end to the WJ nozzle 58, and at the other end to the WJ port 32 on the operation section 17. The WJ port 32 is connected to a syringe 121 or a connecting tube of the syringe 121. By pushing a plunger of the syringe 121 in the axial direction, the solution in the syringe 121 is fed in the WJ channel 54, and discharged from the WJ nozzle 58 to the affected part. The forceps channel 51 of the endoscope 11 is divided at the rear end into two passages, and connected separately to the forceps inlet port 19 and the suction button 31 on the operation section 17. The suction button 31 has two ports: a port 116 linked to the forceps channel 51 and a port 117 linked to a suction connector 118 of the universal connector 18. As shown in detail in FIG. 11, the suction connector 118 is connected to a tube 120 extending from a suction device 119. Pressing the suction button 31 connects the port 116 and the port 117 to allow the suction device 119 to suction dirt, blood and other body fluids from the patient's body through the forceps channel 51 of the endoscope 11, and collect them in a suction tank 123.

As described above, the attachment portion 36 of the assisting tool 12 is attached to the forceps inlet port 19 of the endoscope 11. As shown in FIG. 8, the attachment portion 36 has a connecting channel 122 for connecting the forceps channel 72 to the forceps inlet port 19 of the endoscope 11. Therefore, as the attachment portion 36 is attached to the forceps inlet port 19, the forceps channel 72 of the assisting tool 12 is coupled to the forceps channel 51 of the endoscope 11. In this state, pressing the suction button 31 of the operation section 17 leads to select both the forceps outlet ports 59, 76, and allows suctioning a large volume of dirt, blood and other body fluids through the forceps channels 51, 72 of the endoscope 11 and the assisting tool 12.

Next, with reference to FIG. 12, the operation of the endoscope system 10 is described. The nasal endoscopic examination begins with a previous treatment which includes the application of anesthesia to the nasal cavity behind the nostril and the inferior meatus to facilitate the insertion of the insertion section 16, and the endoscope inserting test to confirm if the insertion section 16 is insertable through this nasal cavity. If this nasal cavity is too small to insert the insertion section 16, anesthesia is applied to the other nasal cavity for insertion of the insertion section 16. The previous treatment is conducted with a patient seating or lying flat on his/her back, and then the insertion section 16 is inserted through a nostril

130 with the patient lying flat or lying on his/her left side.

As shown in FIG. 13, the insertion section 16 is advanced to pass the middle meatus 131 or the inferior meatus 132, a posterior

(internal) nasal aperture 133, the esophagus 134, and then reach the stomach.

When no lesion or wound to be treated is found in the duodenum and the stomach, the insertion section 16 is pulled out . If a lesion is found and it can be treated with the small-diameter forceps channel 51 of the endoscope 11, a compact snare or forceps or such medical instrument is inserted into the forceps channel 51 to medically treat the lesion.

In the case that the found lesion is difficult to treat with a compact medical instrument for some reason, the assisting tool 12 is introduced. Firstly, anesthesia is applied to the nasal cavity behind the other unoccupied nostril for insertion of the insertion section 35 of the assisting tool 12. Then, the insertion section 16 of the endoscope 11 is once pulled back to the area between the posterior nasal aperture 133 and the esophagus 134, so as to tie and advance together the front parts of these two insertion sections 16, 35 of the endoscope 11 and the assisting tool 12. Now, the insertion section 35 of the assisting tool 12 is inserted through the other nostril, and advanced in the middle meatus 131 or the inferior meatus 132 to the area between the posterior nasal aperture 133 and the esophagus 134. The insertion sections 16, 35 are then moved relative to each other to align the front surfaces 20a, 37a, and tied to each other with the magnets 23, 40 and the magnets 24, 41. The bending portions 21, 38 are thereby fastened in parallel to each other, and their front surfaces 20a, 37a face the same direction.

Subsequently, the attachment portion 36 of the assisting tool 12 is attached to the forceps inlet port 19 of the endoscope 11, and the insertion sections 16, 35 are slowly advanced. During this operation, the angle knob 28 is manipulated while viewing the monitor 15 to bend the bending portion 21 of the endoscope 11 in accordance with a tortuous insertion path. Tied with the insertion section 21 of the endoscope 11 by the magnets 23, 24, 40 and 41, the insertion section 38 of the assisting tool 12 is bent and advanced along with the insertion section 21 of the endoscope 11. Therefore, it is only necessary to hold and advance the insertion section 16 of the endoscope 11 to insert the insertion section 35 of the assisting tool 12. Then, while visualizing the affected part to be treated on the monitor 15, a medical instrument is inserted into the forceps channel 72 through the forceps inlet port 42 of the attachment portion 36, and a treatment tool, such as a pair of forcep cups or a choking loop, at the tip of the medical instrument is projected from the forceps outlet port 76 of the assisting tool 12 to treat the affected part.

A typical forceps, an example of the medical instruments, has an operation wire inserted in a flexible sheath, and the pair of forcep cups at a distal end of the operation wire. The proximal end of the operation wire is moved back and forth along the axial direction outside the forceps inlet port to open and close the forcep cups by projecting and retracting them through the sheath. The forceps is used mainly for biopsy, and a typical channel for the forceps generally has an outer diameter of at least 2.8 mm. A typical snare has the choking loop made by looping a distal end of an elastic wire, and a sheath for slidably holding this elastic wire. Pulling back a proximal end of the elastic wire draws the choking loop into the sheath, and the choking loop elastically deforms in a closed shape. Pulling ahead the proximal end of the elastic wire pushes the choking loop out of the sheath, and the choking loop expands to a loop from the closed shape. To remove a polyp with the snare, the choking loop is placed around the base of the polyp to squeeze thereof moderately, and high-frequency current is applied to the choking loop. Burned by this high-frequency current, the body tissues in contact with the choking loop are cut and solidified simultaneously. A typical channel for the snare also generally has an outer diameter of at least 2.8 mm.

The forceps channel 72 of the assisting tool 12 enables a variety of medical treatments using these types of medical instruments, such as a tissue biopsy, removal of a foreign object, hemostasis, tumor removal and gallstone destruction. The assisting tool 12 also serves to accelerate the suctioning of dirt, blood and other body fluids since the forceps outlet port 76 is activated together with the forceps outlet port 59 of the endoscope 11 by pressing the suction button 31 on the operation section 17. Using the forceps outlet ports 59, 76 at once makes it possible to suck more body tissues.

At the end of the treatment, the medical instrument is pulled out through the forceps inlet port 42, and then the insertion sections 16, 35 are both slowly pulled out. Along the way, the insertion sections 16, 35 are untied or disengaged from each other at somewhere between the esophagus and the posterior nasal aperture. This can be easily done by sliding one of the insertion sections 16, 35 in the insertion direction relative to the other until the magnets 23, 24 are separated from the magnets 40, 41. Thereafter, the insertion section 35 of the assisting tool 12 is firstly pulled out, and then the insertion section 16 of the endoscope 11 is pulled out. Lastly, the attachment portion 36 of the assisting tool 12 is detached from the forceps inlet port 19 of the operation section 17.

When it is apparent at first sight that the treatment cannot be performed with the forceps channel 51 of the endoscope 11, the assisting tool 12 may be introduced from the beginning. In this case, the attachment portion 36 can be attached to forceps inlet port 19 either before the insertion section 35 is inserted or after the insertion section 35 is fastened to the insertion section 16.

Although the assisting tool 12 has the attachment portion 36 to be connected to the endoscope 11, the attachment portion 36 may be omitted, and the assisting tool 12 may be used without connecting the proximal end thereof to the endoscope 11. As shown in FIG. 14, an assisting tool 140 has a forceps inlet port 141 and a suction connector 142 separately coupled to the proximal end of the forceps channel 72. The suction connector 142 is connected to a suction device 143. The suction device 143 is provided exclusively for the assisting tool 140, and has a controller 145 and a pump 146. It is preferred in this case to provide a foot switch 144 which is connected to the controller 145 and enables foot control of the sucking operation of the assisting tool 140 so as to reduce hand activities in using the endoscope 11. In this embodiment, the forceps channel 51 of the endoscope 11 and the forceps channel 72 of the assisting tool 12 can be used separately for suctioning. It is therefore possible to harvest large and small body tissues separately using the forceps channel 72 of the assisting tool 12 for the large one, and the forceps channel 51 of the endoscope 11 for the small one.

Meanwhile, many of the nasal endoscopes do not have the WJ nozzle 58. Designed for this type of nasal endoscope is an assisting tool 151 which has, as shown in FIG. 15, a water-jet (WJ) channel 150 for ejecting liquid to an object, in addition to the forceps channel 72. The assisting tool 151 is also provided on the rear end with a water-jet (WJ) port 153 coupled to the WJ channel 150. The WJ port 153 is connected to a water feed device 152. A distal end of the WJ channel 150 is connected to a water-jet (WJ) nozzle 154 formed on the front face 37a of the distal portion 37.

The water feed device 152 includes a water feed pump 155, a controller 156 for controlling the water feed pump 155, a foot switch 157 and a water tank 158 connected to the water feed pump 155. The controller 156 activates the water feed pump 155 in response to the operation of the foot switch 157, and feeds the liquid in the water tank 158 to the assisting tool 151. The liquid is then conveyed in the WJ channel 150, and ejected from the WJ nozzle 154. Having smaller diameters than the forceps channel 76 and the forceps outlet port 76, the WJ nozzle 154 and the WJ channel 150 do not require reducing the diameters of the forceps channel 76 and the forceps outlet port 76. Two or more WJ nozzles 154 may be provided to the assisting tool 151. In this case, an additional WJ channel and an additional WJ port may be provided for each of the WJ nozzles 154 to eject different types of fluids at the same time.

[Second Embodiment]

Next, another embodiment of the present invention is described. Hereafter, elements similar to those in the first embodiment are designated by the same reference numerals, and the detail explanation thereof is omitted.

As shown in FIG. 16, an endoscope system 160 includes an endoscope 161, an assisting tool 162, a light source device 163, a processing device 164 and a monitor 165.

The assisting tool 162 has the insertion section 35 and an auxiliary LG connector 166. The auxiliary LG connector 166 is provided at a leading end of a cord 168 extending from a proximal portion 167 of the insertion section 35, and detachably connected to an auxiliary LG socket 170 of the light source device 163.

The insertion section 35 of the assisting tool 162 contains a light guide in the interior space extending from the distal portion 37 to the proximal portion 167. This light guide conveys illumination light emitted from the light source device 163 to the illumination optical system behind the illumination window on the front face 37a of the insertion section 35.

As shown in FIG. 17, the flexible portion 39 of the assisting tool 162 holds a light guide 172. The light guide 172 is covered and protected by the flexible tube 71. The light guide 172 has a bundle of optical fibers 173 and a protective tube 174 of silicon or such an elastic material to cover the optical fibers 173. The light guide 172 excluding the protective tube 174 has a diameter that is at least 70% of the outer diameter of the insertion section 35 of the assisting tool 12 and is at least twice as large as the diameters of the light guides 48, 49.

As shown in FIG. 18, the distal portion 37 of the assisting tool 162 is covered with a rigid pipe 175. The distal portion 37 retains a lens holding frame 176, which holds an illumination lens 177. The illumination lens constitutes the illumination optical system, and has a front face 117a exposed from an illumination window 178 on the front face 37a. The opposite surface of the illumination lens 177 to the front face 177a is a light entrance surface that faces a light exit end 172a of the light guide 172. For the purpose of providing additional luminous intensity to the endoscope, the illumination lens 177 may be a collecting lens having a convex optical surface. For the purpose of widening the angle of light, the illumination lens 177 may be a diffusing lens having a concave optical surface. Additionally, the illumination lens may be either a single lens or a group of lenses .

As shown in FIG. 19, the light source device 163 includes the light source lamp 97, the light source driver 98, the aperture stop mechanism 99, a luminous intensity limiting mechanism 180, a collecting lens 181 and a CPU 182. The light source lamp 97, the light source driver 98 and the aperture stop mechanism 99 has the same structure as those in the previous embodiment. The luminous intensity limiting mechanism 180 has a luminous intensity limiting filter to be put in and out of an optical path of the illumination light. The luminous intensity limiting filter limits the amount of a predetermined wavelength component in the white light generated from the light source lamp 97 as it is put in the optical path.

The collecting lens 181 collects the light having passed through the aperture stop mechanism 99 and the luminous intensity limiting mechanism 180, and directs it to the light entrance ends of the light guides 48, 49 of the endoscope 161 and the light guide 172 of the assisting tool 162.

The CPU 182 communicates with the CPU 91 of the processing device 164 to obtain the brightness information produced as the video signal is generated, and controls both the amount of light from the light source lamp 97 and the open/close action of the aperture stop mechanism 99, based on the brightness information, to adjust the illumination light.

The light out of the light source lamp 97 is adjusted by the aperture stop mechanism 99, the luminous intensity limiting mechanism 180 and collecting lens 181, and enters, as illumination light, into the light guides 48, 49, 172. The illumination light is then emitted from the illumination windows 56, 57 of the endoscope 161 and the illumination window 178 of the assisting tool 162 to an internal body part of the patient.

As shown in FIG. 20 and FIG. 21, the light source device 163 has a power button 185 on the right side of the front face. Pressing the power button 185 leads to supply or interrupt the electric power from a commercial power source to the light source device 163. Placed side by side on the left side of the power button 185 are a lamp button 186, a dimmer button 187, a luminous intensity limiting button 188, a back-light button 189 and an air feed button 190. On the right side in the front of the light source device 163, there are provided a LG socket 192 detachably fitting onto the LG connector 25 of the endoscope 161, and the auxiliary LG socket 170 detachably fitting onto the auxiliary LG connector 166 of the assisting tool 162. The lamp button 186 is a push-button switch. Pressing the lamp button leads to turn on and off the light source lamp 97. The dimmer button 187 includes an UP button 187a and a DOWN button 187b, and changes the aperture size to provide 10-step brightness adjustment of the illumination light. Instead of changing the aperture size, the brightness of the illumination light can be adjusted by inserting a light attenuation filter or by adjusting the lighting current to the light source lamp 97. The luminous intensity limiting button 188 is a push-button switch, and pressed for placing the luminous intensity limiting filter in and out of the illumination optical path to limit and unlimit the intensity of a predetermined wavelength component in the white light.

The back-light button 189 is pushed to light up the buttons 186, 187, 189 and 190 from the back, for better visibility of the operational buttons in a dark place. The light source device 163 is equipped with the pump 113 and the valve 112 (see, FIG. 8) for feeding air and liquids to the air/water feed channel 52 in the endoscope 161. The air feed button 190 is pressed for controlling the valve 112 to adjust the air feeding pressure in, for example, three steps of low, mid and high. The air feeding pressure selected through the air feed button 190 is transmitted to the CPU 182. Based on this information, the CPU 182 adjusts the valve 112. Before the medical examination using the endoscope 161, it is necessary to determine the brightness and the wavelength of the illumination light in view of the patient's data, the type of examination and the region of interest. An example procedure to do this begins with turning on the power button 185 and the lamp button 186. Then, the dimmer button 187 is manipulated to sufficiently illuminate the region of interest, and the luminous intensity limiting button 188 is turned on if necessary. Lastly, the air feed button 190 is manipulated to select a desired air feeding pressure.

Now, with reference to FIG. 22, the operation of the endoscope system 160 is described. After the previous treatment, the insertion section 16 of the endoscope 161 is inserted through a nostril. While the duodenum and the stomach are clearly visualized on the monitor 165, the examination is continued using only the endoscope 161. Upon finding a lesion or wound, the snare or the forceps or an appropriate medical instrument is inserted in the forceps channel 51 of the endoscope 161 to medically treat that affected part. When the image on the monitor 165 is too dim due to poor illumination, the assisting tool 162 is introduced. In this case, before inserting the assisting tool 162, anesthesia is administered to the nasal cavity behind the other unoccupied nostril. Then, the insertion section 16 of the endoscope 161 is once pulled back to the area between the posterior nasal aperture 133 and the esophagus 134, so as to tie and advance together the front parts of these two insertion sections 16, 35 of the endoscope 161 and the assisting tool 162.

Subsequently, the insertion section 35 of the assisting tool 162 is inserted through the other nostril, and advanced in the middle meatus 131 or the inferior meatus 132 to the area between the posterior nasal aperture 133 and the esophagus 134. The insertion sections 16, 35 are then moved relative to each other to align the front surfaces 20a, 37a, and tied to each other with the magnets 23, 40 and the magnets 24, 41. The bending portions 21, 38 are thereby fastened in parallel to each other, and their front surfaces 20a, 37a face the same direction.

After checking that the lamp button 186 of the light source device 163 is turned off, the auxiliary LG connector 166 of the assisting tool 162 is connected to the auxiliary LG socket 170. The auxiliary LG socket 170 is closed with a cap for preventing the leakage of light, and this cap needs to be removed in advance.

After the connection, the lamp button 186 is pressed to turn on the light source lamp 97. Now, the illumination light is emitted form the illumination windows 56, 57 of the endoscope 161 and the illumination window 178 of the assisting tool 162, providing more brightness inside the patient' s body than the endoscope 161 alone .

As described, the endoscope system 160 allows using the assisting tool 162 with the endoscope 161, and can produce a distinct image on the monitor 165 even if the inside of the patient's body is too dim for the endoscope 161 alone. Thereafter, as with the above embodiment, the insertion sections 16, 35 are advanced together, and the affected part is treated with the medical instrument inserted in the forceps channel 51 of the endoscope 161. At last, the insertion sections 16, 35 are pulled out separately to finish the medical examination.

Although the assisting tool 162 is connected to the light source device 163, it is possible to provide, in the rear end of the assisting tool 162, an attachment portion 194 for connecting the light guide 172 of the assisting tool 162 and the light guides 48, 49 of the endoscope 161 to convey the illumination light from the endoscope 161 to the assisting tool 162.In this case, an auxiliary LG connector 195 or coupler is provided in the attachment portion 194 of the assisting tool 162, and an auxiliary LG socket 196 or coupler to fit onto the auxiliary LG connector 195 is provided in the operation section 17.

The optical fiber bundle in the endoscope 161 has a single light entrance end, and is connected to the light source device via the LG socket 192. This optical fiber bundle is divided on the light exit side into three bundles: the light guides 48, 49 and a branched light guide 197 for guiding the illumination light to the auxiliary LG socket 196. By connecting the auxiliary LG connector 195 to the auxiliary LG socket 196, the branched light guide 197 is coupled to the light guide 172 of the assisting tool 162.

Although the illumination light is generated from a single light source lamp 97, and transmitted to both the endoscope 161 and the assisting tool 162 in the above embodiments, it is possible to provide separate light source lamps for each of the endoscope 161 and the assisting tool 162. FIG. 24 shows an example of this configuration .

As shown in FIG. 24, a light source device 200 has an additional lamp button 201 exclusive for the assisting tool 162, so that the light source lamp 97 for the endoscope 161 and a light source lamp 202 for the assisting tool 162 can be turned on and off separately by the lamp buttons 186, 201 respectively. The light source device 200 also is an auxiliary light source for producing the illumination light for the assisting tool 162, as well as the main light source composed of the elements 97 to 99, 180 to 182 for producing the illumination light for the endoscope 161.

Similar to the main light source, the auxiliary light source is composed of the light source lamp 202, a light source driver 203, an aperture stop mechanism 204, a luminous intensity limiting mechanism 205 and a collecting lens 206. These elements have the same function and structure as those of the main light source.

The endoscope system of FIG. 24 has the separate light source lamps 97 , 202 each for the endoscope 161 and the assisting tool

162, and these lamps 97, 202 are placed together in the light source device 200. The brightness of the illumination light can be adjusted by manual operation of the dimmer button 187 on the light source device 200 to change the aperture size of one or both the aperture stop mechanisms 99, 204 of the endoscope 161 and the assisting tool 162. The most effective way is to change the aperture size of the aperture stop mechanism 204 of the light source device 200 since the assisting tool 162 can produce more amount of light than the endoscope 161. It is therefore convenient to detect the connection of the assisting tool 162, and associate the manipulation of the dimmer button 187 with the aperture size of the aperture stop mechanism 204 while the assisting tool 162 is connected, and with the aperture size of the aperture stop mechanism 99 of the endoscope 161 while the assisting tool 162 is removed.

It may be possible, as shown in FIG. 25, to provide an auxiliary light source device 208 for producing the illumination light for the assisting tool 162, in addition to the light source device 163 for producing the illumination light for the endoscope 161. The auxiliary light source device 208 has the lamp button 201 for the assisting tool 162, the auxiliary light producing mechanism composed of the light source lamp 202, the light source driver 203, the aperture stop mechanism 204, the luminous intensity limiting mechanism 205, the collecting lens 206 and the CPU 207, and an auxiliary LG socket 211 or coupler for fitting onto an auxiliary LG connector 210 or coupler in the attachment portion 209 of the assisting tool 162.

The light source driver 203 is connected to the CPU 207, and controls the amount of light from the light source lamp 202. The CPU 207 communicates with the CPU 91 of the processing device 164 to obtain the brightness information produced as the video signal is generated, and controls both the amount of light from the light source lamp 202 and the open/close action of the aperture stop mechanism 204, based on the brightness information, to adjust the illumination light emitted from the auxiliary light source device 208. In this configuration, the auxiliary light source device 208 may be equipped with a brightness adjusting button to achieve independent brightness control. In the above embodiment, the assisting tool 162 has the illumination instrument based on the light guide 172. However, the illumination instrument may be based on white LEDs such as an assisting tool 215, shown in FIG. 26, which has a plurality of LEDs 216, a driver 217 and an auxiliary LED connector 218. Each of the LEDs 216 is arranged to expose its light emitter to the outside from the front face 37a of the assisting tool 215. The driver 217 is electrically connected to the LEDs 216 through signal wires to drive each LED 216. Preferably, a flexible multicore cable may be used as the signal wire to connect the driver 217 to the LEDs 216.

The auxiliary LED connector 218 is provided on the tip of a cord 219 extending from the proximal end of the assisting tool 215, and connected to an LED controller 220. The LED controller 220 is connected to the processing device 164, and communicates with the CPU 91 of the processing device 164. Receiving the brightness information from the CPU 91, the LED controller 220 adjusts the luminous intensity of the LEDs 216 through the driver 217, based on the brightness information, to provide an optimum observation condition at all times. The LED controller 220 has a lamp button 221. The LEDs 216 are turned on and off by pressing this lamp button 221.

Although the driver 217 is positioned in the rear end of the assisting tool 215 in the drawing, it may be positioned in the front part of the assisting tool 215 or in the LED controller 220. The LEDs 216 may be arranged in a concentric pattern on the front face 37a or in a radial pattern from the center of the front face 37a. Alternatively, the LED controller 220 may be placed in the light source device 163, and the auxiliary LED connector 218 may be connected to the light source device 163.

Although the endoscope 161 in FIG. 26 the illumination instrument based on the light guides 48, 49, the illumination instrument of the endoscope 161 may be based on white LEDs. In this case, a single LED controller may be provided to control both the endoscope 161 and the assisting tool 162, or separate LED controllers may be provided to control them independently.

While the assisting tools 162, 215 only provide the illumination function, they may be configured to provide an additional function, such as the forceps channel. For example, an assisting tool 225 in FIG. 27 has a forceps channel 226 passing through the insertion section 35. This forceps channel 226 is connected at one end to a forceps outlet port 227 on the front face 37a, and at the other end to a forceps inlet port 228 in the rear end of the assisting tools 225. Provided at the rear end of the assisting tool 225 is an attachment portion 229 to be detachably connected to the operation section 17 of the endoscope 161. The attachment portion 229 has a connecting channel 230 that connects the forceps channel 226 of the assisting tool 225 to the forceps inlet port 19 on the operation section 17 as it is attached to the forceps inlet port 19.

As shown in FIG. 28, the forceps outlet port 227 is arranged in parallel to the illumination window 178 on the front face 37a. An additional illumination window may be provided, and in this case the forehead of the light guide 172 may be divided into two paths in the insertion section 35. In the case of using LEDs as the illumination instrument, the LEDs may preferably be arranged around the forceps channel 226, as shown in FIG. 29.

Furthermore, as shown in FIG. 30, a water-jet (WJ) channel 236 for spraying liquids to an object may be added along with the light guide 172. In this case, an assisting tool 235 is also provided with a water-jet (WJ) port 238 for connecting a water feed device 237 to the rear end of the assisting tool 235. The proximal end of the WJ channel 236 is connected to the WJ port

238, and the distal end thereof is connected to a water-jet (WJ) nozzle 239 formed on the front face 37a.

The water feed device 237 includes a water feed pump 240, a controller 241 for controlling the pump 240, a foot switch 242 and a water tank 243 coupled to the water feed pump 240. The controller 241 activates the water feed pump 240 in response to the operation of the foot switch 242, and feeds the liquid in the water tank 243 to the assisting tool 235. The liquid is then conveyed in the WJ channel 236, and ejected from the WJ nozzle

239. Having smaller diameters than the light guide 172, the WJ nozzle 239 and the WJ channel 236 do not require reducing the diameter of the illumination window 178. Two or more WJ nozzles 239 may be provided to the assisting tool 235. In this case, an additional WJ channel and an additional WJ port may be provided for each of the WJ nozzles to eject different types of fluids at the same time. In place of the water feed device 237, a syringe may be connected to the assisting tool 235.

Although the assisting tools of the above embodiments provide the white light, they may be configured to provide special light for enabling the NBI (narrow band imaging) using narrow-spectrum light, the IRI (infra-red imaging) using infrared light, the AFI (auto-fluorescence imaging) using auto-fluorescence excitation light and such special observation. These types of special light are used for effectively visualizing a small lesion that is difficult to observe under the white light. Controlling the waveband of the special light allows for obtaining emphasized images of, for example, the capillaries on a mucosal surface, slight thickening of the mucosal and deep blood vessels. In using the special light, the assisting tool is connected to a special light source device having a special light generating function. The lamp button of the endoscope is manipulated to turn off the white light, and then a lamp button of the special light source device is turned on. The illumination is thereby switched from the white light to the special light, saving the trouble of exchanging the endoscopes.

In the NBI, the region of interest is irradiated by the light in two narrow wavebands (390-445nm and 530-550nm) easily absorbed by the hemoglobin in the blood, so that capillaries on a mucosal surface and the microscopic pattern of the mucosal are emphasized on the monitor . Therefore, the assisting tool may be provided with two illumination windows for separately emitting the light of these two different wavebands.

In the IRI, the infrared light in two wavebands (790-820nm and 905-970nm) is emitted to emphasize the deep blood vessels and the bloodstream that is difficult to observe under the white light. To visualize the deep blood vessels at high contrast, an infrared indicator agent is administered to the patient by intravenous injection. Subsequently, the region of interest is irradiated by the light in the waveband (790-820 run) most-easily absorbed by the infrared indicator agent and the light in the waveband (905-970 run) least-easily absorbed by the infrared indicator agent so as to visualize the submucosal vessels in blue color. Therefore, the assisting tool may be provided with two illumination windows for separately emitting the light of these two different wavebands.

In the AFI, the region of interest is irradiated by the excitation light (390-470 nm) to visualize the fluorescent substances, such as collagen, and by the light in the waveband

(540-560nm) easily absorbed by the hemoglobin in the blood so as to visualize a neoplastic lesion area and normal mucosa in different colors . In this case, the assisting tool may be provided with two illumination windows for separately emitting the light of two different wavebands. The auto-fluorescence is extremely weak light. Therefore, the assisting tool may be combined with an endoscope having a high-sensitivity CCD or such an image sensor.

[Third Embodiment]

Hereinafter described is another preferred embodiment of the present invention which has a magnet of different form.

As shown in FIG. 31, an endoscope system 300 includes an endoscope 301 for capturing an image inside a patient's body, an assisting tool 302 for providing an additional function to the endoscope 301, a light source device 303 for supplying the endoscope 301 with illumination light to illuminate the interior of the patient's body, a processing device 303 for generating an endoscopic image and a monitor 305 for displaying this endoscopic image .

The endoscope 301 includes an insertion section 306 to be inserted into the patient's body, an operation section 307 connected to the proximal end of the insertion section 306 and manipulated by an operator such as a doctor or a technician, and a universal cable 308 connected to the operation section 307 so as to couple the endoscope 301 with the light source device 303 and the processing device 304.

The endoscope 301 contains the forceps channel 51 (see, FIG. 2) extending from the operation section 307 to the leading end of the insertion section 306 for the insertion of a medical instrument, such as a forceps or a snare. The insertion section 306 has a tubular shape with an outer diameter of approximately 6 mm. The forceps channel 51 is a tubular element having an inner diameter of approximately 2 mm.

The assisting tool 302 includes an insertion section 325 to be inserted into the patient' s body, and an attachment portion 326 for attaching the proximal end of the assisting tool 302 to the operation section 307 of the endoscope 301. The insertion section 325 has a tubular shape with an outer diameter substantially identical to or slightly smaller than the insertion section 306 of the endoscope 301. Inside the assisting tool 302, from the attachment portion 326 to the leading end of the insertion section 325, extends the forceps channel 72 (see, FIG. 5) having a larger diameter than the forceps channel 51 of the endoscope 301. The endoscope 301 is a so-called nasal endoscope configured to insert the insertion section 306 through an external naris of the patient. The insertion section 306 of this endoscope 301 has a smaller diameter than the insertion section of a typical oral endoscope being inserted through the mouth. Naturally, the forceps channel 51 in the insertion section 306 has a small diameter. Compared to the oral endoscopes, the nasal endoscopes have a restriction on the size of medical instruments available.

The endoscope system 300 enables a parallel use of the endoscope 301 being inserted through one nostril and the assisting tool 302 being inserted through the other nostril. The forceps channel 72 of the assisting tool 302 aids the function of the forceps channel 51 of the endoscope 301, and allows for using the large medical instruments, typically used with the oral endoscopes, in the medical examination using the endoscope 301 that is the nasal endoscope. Since the forceps channel of a typical oral endoscope has an internal diameter of approximately 3.2 mm, it is preferred that the forceps channel 72 of the assisting tool 302 has an internal diameter of at least 3.2 mm.

Similar to the above embodiments, the insertion section 306 of the endoscope 301 is composed of a distal portion 310, a bending portion 311 and a flexible portion 312. The bending portion 311 is configured to bend in four directions of up, down, right and left in conjunction with an up-down angle knob 313 and a right-left angle knob 314 on the operation section 307. This bending action leads to orient a front face of the distal portion 310 in a desired direction. In addition to the angle knobs 313, 314, the operation section 307 is provided with a forceps inlet port 315 for inserting a medical instrument into the forceps channel 51, an air/water feed button 316 for feeding air and water into the patient' s body, a suction button 317 for suctioning the residual air, the residual liquid and the body fluid from a patient's body, and a water-jet (WJ) port 318 for spraying rinse water, medical solution or other fluid onto an object. The WJ port 318 is detachably connected to a syringe. The rinse water and the drug solution are supplied from this syringe. Normally, the forceps inlet port 315 and the WJ port 318 are closed with detachable stoppers.

The universal cable 308 has, on the opposite end to the operation section 307, an LG connector 320 to be connected to the light source device 303 and an electrical connector 321 to be connected to the processing device 304. The electrical connector 321 is coupled to the LG connector 320 by a cord 322. These connectors 320, 321 permit detachable connection of the endoscope 301 to the devices 303, 304.

The LG connector 320 has two joints: a first joint for connecting a water tank 323 containing the water to be fed to the endoscope 301, and a second joint for connecting a suction device 324 to apply a suction pressure to the endoscope 301. More specifically, the LG connector 320 is connected to the water tank 323 via the first joint and a water feed tube 323a, and to the suction device 324 via the second joint and a suction tube 324a.

The second joint is connected to a suction channel running through the endoscope 301. This suction channel is connected to the forceps channel 51 at the operation section 307, and closed at this connecting point by a valve that operates in response to the press of a suction button 317. While the suction button 317 is kept pressed, the valve opens the suction channel to connect the forceps channel 51 to the suction device 324 by way of the suction channel and the suction tube 324a. The suction device 324 is then activated to suction the air and the liquids in the patient' s body through the tip of the insertion section 306. These suctioned liquids, such as the rinse water and the body fluids, are collected in a suction tank 324b. In this manner, the forceps channel 51 constitutes a part of the suction channel.

The light source device 303 has a light source lamp to emit the illumination light. The light source lamp is arranged to face a light entrance surface of the LG connector 320, so that the illumination light out of the light source lamp enters the light entrance surface. The illumination light incident on the LG connector 320 is conveyed to an illumination optical system in the distal portion 310 by a light guide running inside the endoscope 301, and emitted from the front face of the distal portion 310. The light source device 303 also has a pump for providing air to the endoscope 301. The pumped air is sent to an air channel in the endoscope 301 and to the water feed tube 323a via the LG connector 320.

The water feed tube 323a holds an air conduit for sending the air from the light source device 303 to the water tank 323 to change the pressure within the water tank 323, and a water conduit for withdrawing the water forced out of the water tank 323 due to the pressure change therein. The water conduit is connected through the LG connector 320 to a water channel in the endoscope 301.

The air channel and the water channel in the endoscope 301 are closed by a valve that operates in response to the press of the air/water feed button 316. Through the axis of the air/water feed button 316 passes a hole to leak the air supplied from the light source device 303. Upon the press of the air/water feed button 316, the valve opens one of the air and water channels and closes the other. By closing the hole of the air/water feed button 316 with a finger, the air from the light source device 303 is sent to the air channel and ejected from the tip of the insertion section 306. By pressing the air/water feed button 316, the air channel is closed and the water channel is opened, and the water out of the water tank 323 is discharged from the tip of the insertion section 306.

The air channel and the water channel are attached, on the downstream side from the valve, into the air/water feed channel 52 (see, FIG. 2) . Within the insertion section 306, the air from the light source device 303 and the water from the water tank 323 are conveyed to the tip of the insertion section 306 through the same air/water feed channel 52.

The processing device 304 has an image processing circuit for generating an endoscopic image by applying various types of image processing to the image signal transmitted from an image sensor of the endoscope 301. This image processing circuit converts the endoscopic image into a composite signal and an RGB component signal, and transmits these signals to the monitor 305. The endoscopic image is thereby displayed on the monitor 305. The insertion section 325 of the assisting tool 12 is composed of a distal portion 327 and a flexible portion 328. Similar to the distal portion 310 of the endoscope 301, the distal portion 327 is made of metal or a similar rigid material-. The flexible portion 328 is a long and slender tubular member with flexibility, similar to the flexible portion 312 of the endoscope 301, and connects the distal portion 327 to the attachment portion 326.

The attachment portion 326 is composed of two tubes combined into a substantially T shape, and connected to the insertion section 325 by the intersecting tube. One end of the attachment portion 326 has an inner diameter as large as the outer diameter of the annular forceps inlet port 315. Fitting onto the forceps inlet port 315, this end of the attachment portion 326 attaches the assisting tool 302 to the operation section 307 in a detachable manner.

The other end of the attachment portion 326 constitutes a forceps inlet port 330 for selectively inserting a medical instrument to the forceps channels 51, 72 of the endoscope 301 and the assisting tool 302. Upon attachment to the forceps inlet port 315 of the endoscope 301 through the attachment portion 326, the assisting tool 302 allows a medical instrument to be inserted through the forceps inlet port 330 and the interior path of the attachment portion 326 to the forceps channel 51 of the endoscope 301 or the forceps channel 72 of the assisting tool 302. The forceps inlet port 330 has substantially the same shape as the forceps inlet port 315 of the endoscope 301. Therefore, a stopper for the forceps inlet port 315 can also be used to close the forceps inlet port 330.

As described above, the forceps channel 51 of the endoscope 301 constitutes a part of the suction channel. When the suction button 317 is pressed as the assisting tool 302 is attached to the forceps inlet port 315, the suction is performed simultaneously by the forceps channels 51, 72 of the endoscope 301 and the assisting tool 302 which are interconnected by the T-shaped attachment portion 326. Namely, when combined with the endoscope 301 for the suction operation, the assisting tool 302 can increase a suction rate per unit time.

The flexible portion 312 of the endoscope 301 is configured by the three-layered flexible tube 47, as with the first embodiment. Inside the flexible portion 312, there are contained the light guides 48, 49, the angle wires 50, the forceps channel 51, the air/water feed channel 52, the multicore cable 53 and the water-jet (WJ) channel 54 (see, FIG. 2) . As with the first embodiment, the flexible portion 328 of the assisting tool 302 is also configured by the flexible tube 71, and holds the forceps channel 72.

As shown in FIG. 31 and FIG. 32, on the front part of the insertion section 325 of the assisting tool 302, there is attached a fastening member 340 for fastening the front part of the insertion section 325 to the front part of the insertion section 306 of the endoscope 301. The fastening member 340 has a hollow cylindrical shape with a peripheral surface partially cut out, and includes an arcuate pillar 341 and rings 342, 343 on both ends of the pillar 341. The fastening member 340 is detachably attached to the insertion section 325 by inserting the insertion section 325 in the rings 342, 343.

On the surface of the pillar 341, there are provided an engaging projection 344 and a ferromagnetic body 345. The engaging projection 344 extends linearly throughout the length of the fastening member 340. The engaging projection 344 as whole is substantially cylindrical, and also tapered from the side of the ring 342 to the side of the ring 343 to gradually decrease the degree of projection. The ferromagnetic body 345, as magnetically attractable segment, also extends linearly throughout the length of the fastening member 340, and lies next to the engaging projection 344. The ferromagnetic body 345 is a thin film of iron or such magnetic material. The fastening member 340 excluding the ferromagnetic body 345 is made of an elastic resin material, such as silicone rubber. The flexible portion 328 of the insertion section 325 is configured to have a recess 348 for fitting the fastening member

340. The recess 348 has a depth substantially identical to the thickness of the pillar 341 and the rings 342, 343 of the fastening member 340. Upon attachment of the fastening member 340 to the insertion section 325 by means of the rings 342, 343, the recess 348 positions the fastening member 340 with respect to the axial and circumferential directions in such a manner that the pillar

341, the rings 342, 343 are level with the outer surface of the distal portion 327 and the flexible portion 328, and only the engaging projection 344 upstands from the outer surface.

Each of the rings 342, 343 has the inner diameter slightly smaller than the outer diameter of the corresponding portion of the recess 348. Owing to their elasticity, the rings 342, 343 can hold tight to the recess 348 upon attachment of the fastening member 340 to the insertion section 325.

On a front face 327a of the distal portion 327 opens a forceps outlet port 350 for projecting the leading end of the medical instrument inserted to the forceps channel 72. By contrast, as shown in FIG. 33, there are provided an image capturing window 360, a pair of illumination windows 361, 362, a forceps outlet port 363, an air/water nozzle 364 and a water-jet (WJ) nozzle 365 on a front face 310a of the distal portion 310 of the endoscope 301.

On the surface of the insertion section 306 of the endoscope 301, there are provided an engaging groove 366 for fitting to the engaging projection 344 of the fastening member 340, and a magnet 367 for attracting the ferromagnetic body 345 as the engaging groove 366 fits onto the engaging projection 344. The engaging groove 366, which is configured to receive the engaging projection 344, is a substantially cylindrical groove that extends linearly throughout the distal portion 310 and the bending portion 311, and is tapered from the front face 310a to the bending portion 311 to gradually decrease the degree of depression. The magnet 367 is placed on the outer surface of the distal portion 310 and next to the engaging groove 366 in such a manner that it can stick to the ferromagnetic body 345. The magnet 367 is arranged near to the front face 310a, and is substantially level with the outer surface of the distal portion 310 so that it will not be caught on a body wall during the insertion.

In attaching the insertion section 325 of the assisting tool 302 to the insertion section 306 of the endoscope 301, the insertion sections 325, 306 are firstly arranged parallel to each other, so that the front faces 310a, 327a face the same direction. The insertion sections 325, 306 are then shifted relatively to each other in such a manner that the front face 310a is located behind the fastening member 340 attached to the insertion section 325.

Subsequently, the insertion section 306 is advanced to move its front face 310a closer to the front face 327a of the insertion section 325. During this process, the insertion sections 306, 325 are rotated to bring the outer surface of the distal portion 310 of the insertion section 306 into contact with the rear end of the fastening member 340, as shown in FIG. 34A, until the magnet 367 sticks to the rear end of the ferromagnetic body 345 of the fastening member 340.

Here, the insertion sections 325, 306 are positioned with respect to the circumferential direction, and the engaging projection 344 faces the engaging groove 366. At this point, as shown in FIG. 34A, the engaging projection 344 and the engaging groove 366 do not engage but partially face each other since they are tapered. In FIG. 34A and FIG. 34B, the internal elements of the insertion sections 325, 306 have been eliminated for the sake of clarity. The insertion section 306 is further advanced with the magnet 367 sticking to and sliding on the ferromagnetic body 345 until the front faces 310a, 327a are aligned as shown in FIG. 34B. Now, the engaging projection 344 engages with the engaging groove 366, and the front part of the insertion section 325 of the assisting tool 302 is fastened to the front part of the insertion section 306 of the endoscope 301.

Fixed to the front part of the insertion section 306 in this manner, the insertion section 325 can bend on the flexible portion 328 following the bending action of the flexible portion 312 as the angle knobs 313, 314 are manipulated, and the front face 327a of the assisting tool 302 is oriented in the same direction as the front face 310a of the endoscope 301. This configuration only requires the endoscope 301 to be manipulated even when the assisting tool 302 is combined, and improves the operability of the endoscope system 300.

Since the insertion section 306 is advanced to engage the engaging projection 344 with the engaging groove 366, the insertion section 325 can be visualized on the monitor 305 in fastening the insertion section 306 to the insertion section 325 inside the patient's body. This allows the user to watch the insertion section 325 during the fastening operation including the alignment of the magnet 367 with the ferromagnetic body 345 and the engagement of the engaging projection 344 with the engaging groove 366. Therefore, the insertion sections 325 can be easily fastened to the insertion section 306.

Since the insertion sections 306, 325 are attached together by the ferromagnetic body 345 and the magnet 367, the insertion sections 325 can be more easily fastened to the insertion section 306.

Although the engaging projection 344 and the ferromagnetic body 345 in this embodiment are formed on the fastening member 340 that is detachable to the insertion section 325, they may be integrated with the insertion section 325. Alternatively, the structure of the insertion sections 306, 325 may be switched, so that the fastening member 340 is attached to the insertion section 306 of the endoscope 301. Contrary to this embodiment, the engaging projection may be formed on the insertion section 306, and the engaging groove may be formed on the insertion section 325. Other than the engaging projection and the engaging groove, any conventional structure may be incorporated to fasten the insertion sections 306, 325 mechanically. While this embodiment uses the magnet 367 on the insertion section 306 of the endoscope 301 and the ferromagnetic body 345 on the insertion section 325 of the assisting tool 302, it is possible to provide the magnetic body to the insertion section 306 and the magnet to the insertion section 325, or provide magnets to both the insertion sections 306, 325. The magnet 367 may either be a permanent magnet or an electromagnet . [Fourth Embodiment]

Yet another preferred embodiment of the present invention is described hereafter. As shown in FIG. 35, an endoscope 301 has recesses 370, 372 on both ends of the bending portion 311. These recesses 370, 372 receive rubber bands 374, 376 respectively. The rubber bands 374, 376 have ferromagnetic bodies 375, 377 of iron or the like.

These rubber bands 374, 376 are attached to the recesses 370, 372 in such a manner that the ferromagnetic bodies 375, 377 are aligned in the axial direction of the insertion section 306. It may be possible to provide the recesses 370, 372 and the rubber bands 374, 376 with projections and corresponding grooves that engage with one another to determine the relative positions of the ferromagnetic bodies 375, 377.

The rubber bands 374, 376 have the thickness substantially identical to the depth of the recesses 370, 372. The diameters of the rubber bands 374, 376 are slightly smaller than the diameters of the recesses 370, 372. Owing to their elasticity, the rubber bands 374, 376 can hold tight to the recesses 370, 372, and become substantially level with the outer surface of the insertion section 306 upon attachment to the recesses 370, 372.

As shown in FIG. 36, an assisting tool 380 is composed mainly of an insertion section 382 to be inserted into the patient's body and an attachment section 383 for connecting a proximal end of the insertion section 382 to the forceps inlet port 315 of the endoscope 301 in a detachable manner.

The insertion section 382 has a tubular shape with a diameter substantially identical to or slightly smaller than the insertion section 306 of the endoscope 301, and is made up of a distal portion 384 on the distal side and a flexible portion 385 on the proximal side. The insertion section 382 holds the forceps channel 72 as with the first embodiment. The insertion section 382 has a front face 384a, which exposes a forceps outlet port 36 for projecting the medical instrument inserted to the forceps channel 72. The distal portion 384 and the flexible portion 385 are identical in structure to the distal and flexible portions of the first embodiment, and the detailed explanation thereof is omitted.

The flexible portion 385 has two electromagnets 388, 389 aligned at a predetermined interval on the outer surface. Between the electromagnets 388, 389, a pressure sensor 390 is placed. The electromagnets 388, 389 and the pressure sensor 390 are aligned in the axial direction of the insertion section 382. Additionally, the electromagnets 388, 389 and the pressure sensor 390 are substantially level with the outer surface of the flexible portion 385 so that they will not be caught on a body wall during the insertion.

As shown in FIG. 37A, the electromagnets 388, 389 are arranged to face the ferromagnetic bodies 375, 377 attached to the insertion section 306 as the insertion sections 306, 382 are placed in parallel with the front faces 310a, 384a being aligned. The electromagnets 388, 389 are attached to the ferromagnetic bodies 375, 377 by means of a magnetic force and, as shown in FIG. 37B, the insertion section 382 is fastened in parallel to the front part of the insertion section 306 of the endoscope 301.

The pressure sensor 390 makes contact with the surface of the bending portion 311 of the endoscope 301 as the insertion sections 306, 382 are attached together by the ferromagnetic bodies 375, 377 and the magnets 388, 389. Sensing the contact pressure, the pressure sensor 390 detects that the insertion sections 306, 382 of the endoscope 301 and the assisting tool 380 are attached together at their front parts.

Referring back to FIG. 36, the attachment portion 383 is a tubular element having a substantially T shape, similar to the attachment portion 326 of the third embodiment, and connected to the insertion section 382 by the intersecting tube. One end of the attachment portion 326 is shaped to fit to the forceps inlet port 315, and the other end of the attachment portion 326 constitutes a forceps inlet port 392 for inserting a medical instrument to the forceps channels 51, 72 of the endoscope 301 and the assisting tool 380.

The attachment portion 383 is provided with a magnetizing switch 394 for turning on and off the electromagnets 388, 389, a magnet lamp 395 for indicating the on-off state of the electromagnets 388, 389, and a contact indication lamp 396 for indicating the detection result of the pressure sensor 390. The magnetizing switch 394 is a push button switch, and turns on and off the electromagnets 388, 389 alternately whenever it is pressed. The magnet lamp 395 is turned off while the electromagnets 388, 389 are off, and turned on while the electromagnets 388, 389 are on. The contact indication lamp 396 lights up only while the pressure sensor 390 detects the attachment of the insertion sections 306, 382, and thereby indicates whether the insertion sections 306, 382 are attached together. These elements of the assisting tool 380, including the electromagnets 388, 389, the pressure sensor 390 and the lamps 395, 396 may be powered by the external device, such as the endoscope 301, or by an internal battery of the assisting tool 380. In the third embodiment, the insertion section 325 of the assisting tool 302 is fastened mechanically to the insertion section 306 of the endoscope 301 by firstly attaching the magnet 367 to the ferromagnetic body 345, and then engaging the engaging projection 344 with the engaging groove 366. In this embodiment, by contrast, the insertion sections 306, 382 are attached to each other only by the magnetic force between the ferromagnetic bodies 375, 377 and the electromagnets 388, 389.

This magnetic force alone can fasten the insertion sections 306, 382, and makes it possible to bend the insertion section 382 on the flexible portion 385 following the bending action of the flexible portion 312 as the angle knobs 313, 314 are manipulated, and advance the insertion sections 306, 382 together only by the bending operation of the endoscope 301. Therefore, similar to the third embodiment, the operability of the endoscope system is improved. Additionally, at the end of the medical examination, the insertion sections 306, 382 can be detached from each other by simply pressing the magnetizing switch 394 to turn off the electromagnets 388, 389. This configuration also serves to facilitate the unfastening operation of the insertion sections 306, 382.

Although the electromagnets 388, 389 are provided on the insertion section 382 of the assisting tool 380, and the ferromagnetic bodies 375, 377 are provided on the insertion section 306 of the endoscope 301, it may be possible to provide the magnetic bodies to the insertion section 382 and the electromagnets to the insertion section 306, or provide the electromagnets to both the insertion sections 306, 382. While this embodiment uses the electromagnets, permanent magnets may be used in place of the electromagnets to fasten together the insertion sections .

In this embodiment, the pressure sensor 390 is used as the detecting means. The pressure sensor 390 can, however, be replaced with a mechanical switch such as a limit switch, an optical or magnetic sensor, or any conventional type of detecting means insofar as it can detect the contact between the insertion sections 306, 382. Although the third embodiment is directed to the endoscope system without the detection means, the third embodiment system may incorporate the detection means.

The insertion section 306 in this fourth embodiment is provided with the recesses 370, 372 fitting to the rubber bands 374, 376, but the recesses 370, 372 are not absolutely necessary. For the conventional nasal endoscopes, for example, the rubber bands 374, 376 can be attached to the positions near the front-side connection ring at the interface of the bending and distal portions and near the rear-side connection ring at the interface of the bending and flexible portions. Although the ferromagnetic bodies 375, 377 are attached to the insertion section 306 by means of the rubber bands 374, 376 in this embodiment, they may be formed directly on the surface of the insertion section 306. [Fifth Embodiment]

Hereafter described is yet another preferred embodiment of the present invention in which an insertion section of the assisting tool is fastened to the endoscope with balloons or the like.

As shown in FIG. 38, an endoscope system 400 includes an endoscope 401, an assisting tool 402, a light source device 403, a processing device 404 and a monitor 405. The endoscope 401 includes an insertion section 406, an operation section 407 and a universal cable 408. The insertion section 406 holds the forceps channel 51 (see, FIG. 2) . The assisting tool 402 includes an insertion section 425 and an attachment portion 426.

The insertion section 406 includes a distal portion 406, a bending portion 411 and a flexible portion 412. The bending portion 411 is configured to bend in four directions of up, down, right and left in accordance with the manipulation of an up-down angle knob 413 and a right-left angle knob 414 on the operation section 407. The flexible portion 412 is a long and slender tubular member with flexibility, and connects the bending portion 411 to the operation section 407.

In addition to the angle knobs 413, 414, the operation section 407 is provided with a forceps inlet port 415 , an air/water feed button 416, a suction button 417 and a water-jet (WJ) port

418. The forceps inlet port 415 and the WJ port 418 are closed with detachable stoppers.

The universal cable 408 has an LG connector 420 and an electric connector 421. The electric connector 421 is coupled to the LG connector 420 through a cord 422. The endoscope 401 is connected through the LG connector 420 and the electric connector 421 to the light source device 403 and the processing device 404 in a detachable manner.

The LG connector 420 is connected to a water tank 423 via a first joint and a water feed tube 423a, and to a suction device 424 via a second joint and a suction tube 424a. The suction device 424 has a suction tank 424b to collect dirt, blood and other body fluids suctioned from the patient's body. The insertion section 425 of the assisting tool 402 is composed of a distal portion 427 and a flexible portion 428. The distal portion 427 is made of metal or a similar rigid material. The flexible portion 428 is a long and slender tubular member with flexibility, and connects the distal portion 427 to the attachment portion 426.

The insertion section 425 has a pair of annular balloons (retainers) 430, 431 in the front part. Made of polyurethane or a similar resin material, these balloons 430, 431 are designed to expand only to a predetermined dimension. Additionally, each of the balloons 430, 431 has a smoothed surface to protect a body wall from damaging during the insertion of the insertion section 425. The balloons 430, 431 are provided for fastening the front part of the insertion section 425 of the assisting tool 402 to the front part of the insertion section 406 of the endoscope 401. FIG. 38 shows the balloons 430, 431 in an expanded state.

A tube 432 is branched from the proximal end of the insertion section 425. This tube 432 connects the insertion section 425 to a syringe pump 433 for expanding or shrinking the balloons 430, 431. The tube 432 is made of rubber or the like, and has flexibility.

The syringe pump 433 blows or draws air in accordance with the push or pull of a piston 433a. Pushing the piston 433a moves air in to the balloons 430, 431 from the syringe pump 433, and the balloons 430, 431 are expanded. Pulling the piston 433a moves air out of the balloons 430, 431 to the syringe pump 433, and the balloons 430, 431 are shrunk. In this manner, the balloons 430, 431 are expanded or shrunk by manipulating the syringe pump 433. It should be noted that the balloons 430, 431 may be expanded by- water or any fluid instead of by air.

The attachment portion 426 is composed of two tubes combined into a substantially T shape (see, FIG. 40) , and connected to the insertion section 425 by the intersecting tube. One end of the attachment portion 426 has an inner diameter as large as the outer diameter of the annular forceps inlet port 415. Fitting onto the forceps inlet port 415, this end of the attachment portion 426 attaches the assisting tool 402 to the operation section 407 in a detachable manner.

The other end of the attachment portion 426 constitutes a forceps inlet port 434 for selectively inserting a medical instrument to the forceps channel 51 of the endoscope 401 and a forceps channel 440 (see, FIG. 39) of the assisting tool 402. Upon attachment to the forceps inlet port 415 of the endoscope 401 through the attachment portion 426, the assisting tool 402 allows a medical instrument to be selectively inserted to the forceps channel 51 of the endoscope 301 or the forceps channel 440 of the assisting tool 402 through the forceps inlet port 434 and the interior path of the attachment portion 426. The forceps inlet port 434 has substantially the same shape as the forceps inlet port 415 of the endoscope 401. Therefore, a stopper for the forceps inlet port 415 can also be used to close the forceps inlet port 434. When the suction button 417 is pressed while the assisting tool 402 is attached to the forceps inlet port 415, the suction is performed simultaneously by the forceps channels 51, 440 of the endoscope 401 and the assisting tool 402 which are interconnected by the T-shaped attachment portion 426. Namely, when combined with the endoscope 401 for the suction operation, the assisting tool 402 can increase a suction rate per unit time.

The flexible portion 412 of the endoscope 401 is configured by the three-layered flexible tube 47, as with the first embodiment. Inside the flexible portion 412, there are contained the light guides 48, 49, the angle wires 50, the forceps channel 51, the air/water feed channel 52, the multicore cable 53 and the water-jet (WJ) channel 54 (see, FIG. 2) .

As shown in FIG. 39, the flexible portion 428 of the assisting tool 402 is configured by a three-layered flexible tube 438 composed of a spiral tube 435, a net 436 and a protective layer 437. The flexible tube 438 holds a forceps channel 440 and a balloon pumping channel 441. These channels 440, 441 consist, for example, flexible resin tubes. The forceps channel 440 guides the medical instrument inserted through the forceps inlet port 434 to the distal portion 427. The balloon pumping channel 441 transfers air between the balloons 430, 431 and the syringe pump 433. As shown in FIG. 40, the distal portion 427 has a front face 427a that exposes a forceps outlet port 442 for projecting a leading end of the medical instrument inserted to the forceps channel 440. The flexible portion 428 has two recesses 443, 444 or plugs on the outer surface for attaching the balloons 430, 431. Each of the recesses 443, 444 is formed by depressing the outer surface of the flexible tube 438 in a substantially circular shape. These recesses 443, 444 are aligned in the axial direction of the insertion section 425.

Each of the balloons 430, 431 has one of discoid attachments 430a, 431a or necks to fit in the recesses 443, 444. These attachments 430a, 431a have through holes that open in the center of the attachments 430a, 431a throughout to the internal spaces thereof. Namely, the attachments 430a, 431a function as a vent hole for transferring air to expand or shrink the balloons 430, 431.

The balloons 430, 431 are attached to the insertion section 425 in a detachable manner by engaging the attachments 430a, 431a with the recesses 443, 444. Each of the recesses 443, 444 has a substantially semicircular groove on the inner side wall, and each of the attachments 430a, 431a has a substantially semicircular flange. Upon attachment of the balloons 430, 431 to the insertion section 425, the semicircular flanges engage with the semicircular grooves to prevent the balloons 430, 431 from running off the insertion section 425, and to fasten the recesses 443, 444 with the attachment 430a, 431a airtight.

For the sake of convenience, the balloons 430, 431 are shown in FIG. 40 as if they are attached to the insertion section 425 with facing to the plane of the drawing. In fact, however, the balloons 430, 431 are attached to the insertion section 425 with facing in the axial direction of the insertion section 425, as shown in FIG. 38. One end 441a of the balloon pumping channel 441 is connected to the tube 432. The other end 441b of the balloon pumping channel 441 is connected to the leading recess 443. The balloon pumping channel 441 has a branched channel 441c, which is connected to the following recess 444. In this manner, the balloons 430, 431 are connected to the syringe pump 433 by means of the tube 432 and the balloon pumping channel 441, and expanded or shrunk by the push or pull of the piston 433a.

To fasten the insertion section 425 of the assisting tool 402 to the insertion section 406 of the endoscope 401 at their front parts, the syringe pump 433 is firstly manipulated to pump up the balloons 430, 431. Then, as shown in FIG. 41A, the insertion sections 406, 425 are paralleled to orient the front parts 410a, 427a in the same direction, and they are positioned to locate the front face 410a of the insertion section 406 behind the balloon 431 on the insertion section 425.

Subsequently, as shown in FIG. 41B, the insertion section 406 is advanced and inserted into the balloons 430, 431 to move the front face 410a of the insertion section 406 closer to the front face 427a of the insertion section 425 until the front faces 410a, 427a are aligned.

To facilitate the insertion of the insertion section 406, each of the balloons 430, 431 is configured to have an inner diameter slightly larger than the outer diameter of the insertion section 406. Additionally, the balloon 430 is positioned proximal to the front part of the bending portion 411 as the front faces 410a, 427a are aligned. Further, the balloon 431 is positioned proximal to the rear end of the bending portion 411 as the front faces 410a, 427a are aligned.

As the insertion section has been inserted in the balloons 430, 431, and the front faces 410a, 427a have been aligned, the syringe pump 433 is manipulated to draw air and shrink the balloons 430, 431. The inner diameters of the balloons 430, 431 are reduced as the balloons 430, 431 are shrunk. In FIG. 41C, the balloons

430, 431 being shrunk hold the insertion section 406, and fasten together the front parts of the insertion sections 406, 425.

Fixed to the insertion section 406 in this manner, the insertion section 425 can bend on the flexible portion 428 following the bending action of the flexible portion 411 as the angle knobs 413, 414 are manipulated, and the front face 427a of the assisting tool 402 is oriented in the same direction as the front face 410a of the endoscope 401. This configuration only requires the endoscope 401 to be manipulated even when the assisting tool 402 is combined, and improves the operability of the endoscope system 400.

This embodiment that uses the balloons 430, 431 enables the fastening of the insertion sections 406, 425 without any modification of the endoscope 401. It is therefore possible to combine the assisting tool 402 with the existing endoscopes. Since the front part 410a has the image capturing window 55, the balloons 430, 431 are visualized on the monitor 405 in inserting the insertion section 406 into the balloons 430, 431. The user can confirm the positions of the balloons 430, 431, and thus the insertion section 406 can be easily inserted into the balloons 430, 431.

At the end of the medical examination, the insertion sections 406, 425 can be detached from each other by simply pumping up the balloons 430, 431 again and pulling out the insertion section 406. Therefore, this configuration serves to facilitate the unfastening operation of the insertion sections 406, 425.

Although the balloons 430, 431 are attached on the insertion section 425 by the engagement of the attachments 430a, 431a with the recesses 443, 444, they may be attached by any other method.

For example, two projections coupled to the balloon pumping channel 441 may be provided on the insertion section 425, and the through holes of the balloons 430, 431 may be inserted in these projections. The balloons 430, 431 are not necessarily attached in a detachable manner to the insertion section 425, and instead they may be fastened with adhesive or the like to the insertion section 425.

While this embodiment uses the syringe pump 433 to expand or shrink the balloons 430, 431, a rotary pump or any conventional pump may be used instead for this purpose.

The insertion section 406 of the endoscope 401 is retained by the annular balloons 430, 431, but as shown in FIG. 42A and FIG. 42B, it may be retained by a tubular balloon 446. Since the balloon 446 of this sleeve shape can be expanded and shrunk through a single through hole, the branched channel 441c of the balloon pumping channel 441 can be omitted. Therefore, with the tubular balloon 446, the balloon pumping channel 441 can have a simpler configuration than with the annular balloons 430, 431.

As a matter of course, the tubular balloon 446 can be expanded and shrunk through two or more through holes. Additionally, for better contact of the insertion sections 406, 425 of the endoscope 401 and the assisting tool 425, the balloon 446 may preferably be attached at the both ends and the center thereof to the insertion section 425.

The insertion sections can be fastened together by any other means than the balloons. For example, an assisting tool 450 in FIG. 43 is provided with a restraint channel 452 for inserting a retaining device or a snare 451, in addition to the forceps channel 440. The insertion section 406 of the endoscope 401 is retained by a retaining loop 453 at the tip of the snare 451 being inserted in the restraint channel 452, and fastened to the insertion section 425.

The restraint channel 452 is smaller in inner diameter than the forceps -channel 440, and connected at one end to a channel exit 454 in the front part of the assisting tool 450 and at the other end to a channel entrance 455 in the rear end of the assisting tool 450. The snare 451 can slide back and forth in the restraint channel 452. The snare 451 is provided, on the tip, with the openable retaining loop 453 made by folding an elastic wire. The rear end of the snare 451 is provided with a handle 456 to project from the channel entrance 455.

As the handle 456 is pushed and pulled, the retaining loop 453 moves between a retracted position within the restraint channel 452 and a proj ected position outside the restraint channel 452. This retaining loop 453 is previously shaped to expand to a circle as it is pushed out of the restraint channel 452. The retaining loop 453 is put in the retained position during the insertion of the insertion section 425 through the exterior nostril.

In fastening the insertion sections 406, 425 together, the retaining loop 453 is pushed out of the restraint channel 452, and expanded to the circular shape. The insertion section 406 of the endoscope 401 is inserted in this expanded retaining loop 453, and then the handle 456 is pulled to close the retaining loop 453. In this manner, by changing the length out of the restraint channel 452, the retaining loop 453 holds the insertion section 406, and fastens it to the insertion section 425. Namely, the snare 451 with the retaining loop 453 can provide the same fastening effect as the balloons .

To make the insertion section 425 easily follow the bending action of the insertion section 406, the channel exit 454 is preferably positioned in the vicinity of the proximal end of the distal portion 427. Additionally, the retaining loop 453 in FIG. 43 is made of an elastic wire, the retaining loop may be made of a resin thread, a thin metallic wire or any conventional string-like material having enough strength to hold the insertion sections 406. With either string-like material, the retaining loop 453 is preferably shaped to expand to a circular shape as it is pushed out of the restraint channel 452, otherwise the retaining loop 453 remains closed even outside the restraint channel 452, and hardly holds the insertion section 406.

This embodiment uses the annular balloons or the elastic wire loop to hold the insertion section 406 of the endoscope 401. Instead of the balloons and the loop, however, a clip-like member or any other retaining member may be provided on the insertion section of the assisting tool so as to hold the insertion section of the endoscope and fastening these insertion sections together. [Sixth Embodiment]

Hereinafter described is yet another preferred embodiment in which a tubular guide member is added to the assisting tool. As shown in FIG. 44, an endoscope system 500 includes an endoscope 501, an assisting tool 502, a light source device 503, a processing device 504 and a monitor 505, similar to the endoscope systems of above embodiments. The endoscope 501 includes an insertion section 506, an operation section 507 and a universal cable 508. Through the endoscope 501 runs the forceps channel 51 (see, FIG. 2) . The assisting tool 502 includes an insertion section 525, an attachment portion 526 and a guide member 527 for guiding the insertion section 525 along with the insertion section 506 of the endoscope 501.

The insertion section 506 includes a distal portion 510, a bending portion 511 and a flexible portion 512. The bending portion 511 is configured to bend in four directions of up, down, right and left in accordance with the manipulation of an up-down angle knob 513 and a right-left angle knob 514 on the operation section 507. The flexible portion 512 is a long and slender tubular member with flexibility, and connects the bending portion 511 to the operation section 507.

In addition to the angle knobs 513, 514, the operation section 507 is provided with a forceps inlet port 515, an air/water feed button 516, a suction button 517 and a water-jet (WJ) port 518. The forceps inlet port 515 and the WJ port 518 are closed with detachable stoppers.

The universal cable 508 has an LG connector 520 and an electric connector 521. The electric connector 521 is coupled to the LG connector 520 through a cord 522. The endoscope 501 is connected through the LG connector 520 and the electric connector 521 to the light source device 503 and the processing device 504 in a detachable manner.

The LG connector 520 is connected to a water tank 523 via a first joint and a water feed tube 523a, and to a suction device 524 via a second joint and a suction tube 524a. The suction device 524 has a suction tank 524b to collect dirt, blood and other body fluids suctioned from the patient's body. The insertion section 525 of the assisting tool 502 is composed of a distal portion 528 and a flexible portion 529. The distal portion 528 is made of metal or a similar rigid material. The flexible portion 529 is a long and slender tubular member with flexibility, and connects the distal portion 528 to the attachment portion 526.

The attachment portion 526 is composed of two tubes combined into a substantially T shape, similar to the above embodiments. One end of the attachment portion 526 can fit to the forceps inlet port 515, and thus attaches the assisting tool 502 to the operation section 507. The other end of the attachment portion 526 constitutes a forceps inlet port 530 for inserting a medical instrument to the forceps channel 51 of the endoscope 401 and a forceps channel 544 (see, FIG. 48) of the assisting tool 502. The guide member 527 constitutes a substantially tubular passage, or channel, having the length substantially identical or slightly shorter than the insertion section 506 of the endoscope 501. This guide member 527 and the insertion section 525 of the assisting tool 502 are arranged parallel to each other with their tip being aligned, and fastened together with adhesive. Configured in this manner, the guide member 527 holds the insertion section 506 of the endoscope 501, and moves together the insertion sections 506, 525 of the endoscope 501 and the assisting tool 502. The guide member 527 is made of flexible and transparent biocompatible plastic material, such as polypropylene, polyurethane or nylon. Made of the transparent material of this kind, the guide member 527 allows a certain level of visual inspection even with the endoscope 501 inserted halfway into the guide member 527.

On the outer surface of the guide member 527, a plurality of access window portions 532 are formed to accept the passage of the insertion section 506 of the endoscope 501 into the guide member 527. These window portions 532 are arranged in a line at predetermined intervals along the axial direction of the guide member 527. As shown in FIG. 45, each of the window portions 532 is composed of a through hole 533 on the outer surface of the guide member 527, and a pair of guide flaps 534, 535. The through hole 533 has a long elliptical shape elongated in the direction crosswise to the axial direction of the guide member 527. The long axis of the through hole 533 is made slightly longer than the diameter of the insertion section 506 to easily swallow the insertion section 506. The through hole 533 is covered with the guide flaps 534, 535, which block the body fluid and other fluids from entering into the through hole 533 as the guide member 527 is inserted in the patient's body.

The guide flaps 534, 535 are beveled, and overlapped with their long sides facing outward, just like the front collars of a robe. Additionally, as shown in FIG. 46A, the guide flaps 534, 535 are slightly elevated from the outer surface of the guide member 527.

Configured in this manner, the guide flaps 534, 535 broaden the entrance of the window portion 532 toward proximal end of the guide member 527, and catch the tip of insertion section 506 that is advanced from the proximal end of the guide member 527. The insertion section 506 is therefore easily inserted in the through hole 533.

More particularly, in inserting the insertion section 506 into the guide member 527 through one of the window portions 532, the insertion section 506 is firstly advanced along the guide member 527, as shown in FIG. 46A, toward the window portion 532. The insertion section 506 is then placed in between the guide flaps 534, 535, and thus roughly positioned to the window portion 532. Subsequently, as shown in FIG. 46B, the insertion section 506 is pushed into the guide flaps 534, 535 in such a manner that the surface of the guide member 527 is depressed obliquely. As it is further advanced, the insertion section 506 is guided to the through hole 533 by the guide flaps 534, 535, and inserted into the guide member 527, as shown in FIG. 46C, through the through hole 533.

As shown in FIG. 47, the tip of the guide member 527 has an inwardly projecting rim 536 that narrows the diameter of the guide member 527 to define an aperture 538 for exposing a front face 510a of the insertion section 506. The diameter of the aperture 538 is slightly smaller than the outer diameter of the insertion section 506. Therefore, the rim 536 makes contact with the front surface 510a and stops it from projecting as the insertion section 506 is inserted in the guide member 527. Now, the guide member 527 fastens the insertion sections 506, 525 together with their front face being aligned.

The endoscope 501 is inserted through one of the nostrils, and so does the assisting tool 502 through the other. The insertion section 525 and the guide member 527 are advanced to the area between the posterior nasal aperture and the stomach. Thereafter, the insertion section 506 of the endoscope 501 is inserted into the guide member 527 through one of the window portions 532. The insertion section 506 is advanced in the guide member 527 until the front face 510a touches the rim 536, and thereby the insertion sections 506, 525 are fastened together with their front faces being aligned.

Fixed to the insertion section 506 by the guide member 527 in this manner, the insertion section 525 can bend on the flexible portion 529 following the bending action of the flexible portion 511 as the angle knobs 513, 514 are manipulated, and a front face 528a (see, FIG. 49) of the assisting tool 502 is oriented in the same direction as the front face 510a of the endoscope 501. This configuration only requires the endoscope 501 to be manipulated even when the assisting tool 502 is combined, and improves the operability of the endoscope system 500. As shown in FIG. 48, the flexible portion 529 of the assisting tool 502 is configured by a three-layered flexible tube 543 composed of a spiral tube 540, a net 541 and a protective layer 542. The flexible tube 543 holds a synthetic resin-made flexible tube, or namely a forceps channel 544. This forceps channel 544 guides the medical instrument being inserted through the forceps inlet port 530 to the distal portion 528.

As shown in FIG. 49, the front face 528a of the distal portion 528 has a forceps outlet port 546 for projecting the tip of the medical instrument being inserted in the forceps channel 544. Referring back to FIG. 48, the guide member 527 has a thin wall 550 defining a hollow cylindrical shape, and eight ribs 552 on the inner surface of the thin wall 550. As described above, the thin wall 550 and the ribs 552 are made of biocompatible plastic material to provide flexibility. The thin wall 550 is approximately 0.3 mm in thickness. The ribs 552 are semi-cylindrical projections extending in the axial direction of the guide member 527, and are evenly spaced from one another. Each of the ribs 552 projects inwardly by approximately 0.5 mm from the thin wall 550. An inscribed circle of the ribs 552 is approximately 6.2 mm in diameter, which is slightly larger than the outer diameter of the insertion section 506 of the endoscope 501 so as to facilitate the insertion of the insertion section 506.

Only with the thickness of the thin wall 550, the guide member 527 cannot provide enough strength to endure the insertion of the endoscope 501, and may easily sag to impede the insertion of the insertion section 506. Only with the thickness of the rib 552, on the other hand, the guide member 527 is no longer flexible, though it provides enough strength, and complicates the insertion and the bending action of the insertion section 525 within the patient's body. By contrast, when composed of the thin wall 550 and the ribs 552, the guide member 527 can provide enough strength while offering adequate flexibility. It is therefore possible to improve the insertability of the insertion section 506 without impeding the insertion and the bending action of the insertion section 525. Additionally, the ribs 552 serve to decrease the area of contact with the insertion section 506, and the insertability of the insertion section 506 to the guide member 527 can therefore be improved.

At the insertion of the assisting tool 502 through the nostril, the guide member 527 is folded, as shown in FIG. 50, to follow the outer surface of the insertion section 525. In this folded state, the guide member 527 can be easily inserted without impeding the insertion of the insertion section 525.

This embodiment uses the guide flaps 534, 535 overlapped like the collars of a robe as a guide means. However, the guide means may have any other configuration to guide the approaching insertion section 506 to the through hole 533.

While the guide member 527 has the rim 536 to align the front faces of the insertion sections 506, 525, the guide member 527 may be configured to project the insertion section 506.

Although the length of the guide member 527 is identical to or slightly shorter than the insertion section 506 in this embodiment, the guide member 527 may be even shorter to hold only the distal portion of the insertion section 506. In this case, there is no need of inserting the insertion section 506 from the midpoint of the guide member, and the window portions 532 of the guide member may be omitted. [Seventh Embodiment]

Hereinafter described is yet another preferred embodiment of the present invention which includes an adapter with a T-shaped flow path as an accessory. As shown in FIG. 51, an endoscope system 600 includes an endoscope 601, an assisting tool 602, a light source device 603, a processing device 604 and a monitor 605, similar to the endoscope systems of above embodiments. The endoscope system 600 is also provided with an adapter 606 for detachably connecting the assisting tool 601 to the endoscope 601.

The endoscope 601 includes an insertion section 607, a handling section 608, an operation section 609 and a universal cable 610. The universal cable 610 has a universal connector 611 at the distal end. The insertion section 607 is composed of a distal portion

612, a bending portion 613 and a flexible portion 614. On both sides of the bending portion 613 is provided a pair of annular magnets 615, 616 for attracting the front part of the assisting tool 602. Similar to the first embodiment, the insertion section 607 holds the light guides 48, 49, the angle wires 50, the air/water feed channel 52, the multicore cable 53 and the WJ channel 54.

The handling section 608 has a forceps inlet port 617 for inserting a medical instrument into the forceps channel 51. The operation section 609 has an angle knob set 618, an air/water feed button 619, a suction button 620 and a WJ port 621.

The universal connector 611 is composed of an LG connector

622 to be detachably connected to the light source device 603, and an electric connector 623 to be detachably connected to the processing device 604. The electrical connector 623 is coupled to the LG connector 622 by a cord 624.

The assisting tool 602 includes an insertion section 625 for providing an additional function to the endoscope 601. This insertion section 625 is composed of a distal portion 626, a bending portion 627 and flexible portion 628. The flexible portion 628 has a proximal end 629 to be detachably attached to the adapter 606. On both sides of the bending portion 627 in the insertion direction, there is provided a pair of annular magnets 630, 631. These magnets 630, 631 attract the magnets 615, 616 of the endoscope 601. Their magnetic forces fasten the assisting tool 602 to the endoscope 601, and thereby the bending portion 627 of the assisting tool 602 can follow the bending action of the bending portion 613 of the endoscope 601, and a front face of the distal portion 626 of the assisting tool 602 faces the same direction as the front face of the distal portion 612 of the endoscope 601.

As shown in FIG. 52, the assisting tool 602 has a forceps channel 632 that passes throughout the assisting tool 602. The assisting tool 602 also has a forceps outlet port 633 on a front face of the distal portion 626, and a forceps inlet port 634 at the proximal end 629.

As better seen in FIG. 53, the adapter 606 has an endoscope mount 640 or connection portion for detachably attaching the handling section 608 of the endoscope 601, an endoscope port 640a to be coupled with the forceps inlet port 617 of the endoscope 601, an assisting tool mount 641 for detachably attaching the proximal end 629 of the assisting tool 602, an assisting tool port 641a or connection portion to be coupled with the forceps inlet port 634 of the assisting tool 602, and an instrument port 642 for inserting a medical instrument into one of the forceps channels 51, 632 of the endoscope 601 and the assisting tool 602.

The instrument port 642 is coupled to both the endoscope port 640a and the assisting tool port 641a by means of a bifurcated channel. In this manner, the adapter 606 is configured to connect the endoscope 601 to the assisting tool 602, and the forceps channel 51 to the forceps channel 632 through the bifurcated channel . The medical instrument inserted through the instrument port 642 can be turned toward one of the ports 640a, 641a, and selectively inserted to one of the forceps channels 51, 632. The endoscope mount 640 and the assisting tool mount 641 have elastic engaging grooves 640b, 641b respectively. These engaging grooves 640b, 641b are configured to engage with corresponding projections 617a, 634a of the forceps inlet ports 617, 634 in a detachable manner, facilitating the attachment thereof.

The adapter 606 is equipped with a detachable channel stopper 643 as a lid. Composed of a hinge 643a and an elastic plug 643b having a slit to be push-opened by the medical instrument, this channel stopper 643 closes the instrument port 642 to prevent the body fluids and other solutions from leaking through the instrument port 642.

In the medical treatment or examination using the endoscope 601, the assisting tool 602 is attached to the handling section 608 via the adapter 606 before or after the insertion of the insertion sections 607, 625. In the case of fastening after the insertion, the assisting tool 602 is preferably advanced further than the endoscope 601 in the patient's body for the subsequent operation.

Although the adapter 606 has a single instrument port 642 connected to both the forceps channels 51, 632 of the endoscope 601 and the assisting tool 602 , the adapter may have two instrument ports separately connected to one of the forceps channels, such as an adapter 650 in FIG. 54.

This adapter 650 includes an endoscope mount 651 for connecting the handling section 608 of the endoscope 601, an assisting tool mount 652 for detachably attaching the proximal end 629 of the assisting tool 602, a first instrument port 653 for inserting a medical instrument into the forceps channels 51 of the endoscope 601, and a second instrument port 654 for inserting a medical instrument into the forceps channels 632 of the assisting tool 602. The endoscope mount 651 has an endoscope port 651a to be coupled with the forceps inlet port 617 of the endoscope 601. The assisting tool mount 652 has an assisting tool port 652a to be coupled with the forceps inlet port 634 of the assisting tool 602.

The first instrument port 653 is coupled to the endoscope port 651a through a channel 655. The second instrument port 654 is coupled to the assisting tool port 652a through a channel 656.

The adapter 650 is equipped with two channel stoppers 657,

658 for the first and second instrument ports 653, 654.

Enabling parallel access to the forceps channels 51, 632 through the instrument ports 653, 654, the adapter 650 allows two medical instruments to be used at the same time. [Eighth Embodiment]

Hereinafter described is still yet another preferred embodiment of the present invention in which the assisting tool has a suction valve.

As shown in FIG. 55, an endoscope system 700 includes an endoscope 701, an assisting tool 702, a light source device 703, a processing device 704 and a monitor 705, similar to the endoscope systems of above embodiments. The endoscope 701 includes an insertion section 706, a handling section 707, an operation section 708 and a universal cable 709. The universal cable 709 has a universal connector 710 at the distal end.

The insertion section 706 is composed of a distal portion 712, a bending portion 713 and a flexible portion 714. On both sides of the bending portion 713 is provided a pair of annular magnets 715, 716 for attracting the front part of the assisting tool 702. Similar to the first embodiment, the insertion section 706 holds the light guides 48, 49, the angle wires 50, the forceps channel 51, the air/water feed channel 52, the multicore cable 53 and the WJ channel 54. The handling section 707 has a forceps inlet port 717 for inserting a medical instrument into the forceps channel 51. The operation section 708 has an angle knob set 718, an air/water feed button 719, a suction button 720 and a WJ port 721.

The universal connector 710 is composed of an LG connector 722 to be detachably connected to the light source device 703, and an electric connector 723 to be detachably connected to the processing device 704. The electrical connector 723 is coupled to the LG connector 722 by a cord 724.

The forceps inlet port 717 is covered with a detachable channel stopper 725. This channel stopper 725 has an elastic plug having a slit to be push-opened by the medical instrument, and closes the forceps inlet port 717 to prevent the body fluids and other solutions from leaking through the forceps inlet port 717. The WJ port 721 is normally covered with a detachable stopper (not shown) having the same configuration as the channel stopper 725.

The assisting tool 702 has an insertion section 727, an attachment portion 728, a forceps inlet port 729 and a suction valve 730. The insertion section 727 has a distal portion 732, a bending portion 733 and a flexible portion 734. On both sides of the bending portion 733 in the insertion direction, there are provided a pair of annular magnets 735, 736. These magnets 735, 736 attract the magnets 715, 716 of the endoscope 701. Their magnetic forces fasten the assisting tool 702 to the endoscope 701, and thereby the bending portion 733 of the assisting tool 702 can follow the bending action of the bending portion 713 of the endoscope 701, and a front face of the distal portion 732 of the assisting tool 702 faces the same direction as the front face of the distal portion 712 of the endoscope 701.

The attachment portion 728, the forceps inlet port 729 and the suction valve 730 are provided in a proximal portion 738 of the insertion section 727. The attachment portion 728 is attached to the forceps inlet port 717 of the endoscope 701 in a detachable manner. The attachment portion 728 has an elastic engaging groove 728a on the inner surface. This engaging groove 728a is configured to engage with a corresponding flange 717a around the forceps inlet port 717 of the endoscope 701 for easy attachment. The attachment portion 728 is covered with a detachable stopper 739, which prevents the body fluids and other solutions from leaking through the forceps channel of the assisting tool 702.

As shown in FIG. 56, the assisting tool 702 has a forceps channel 740 within the interior space passing throughout the length between the distal portion 732 and the proximal portion 738. This forceps channel 740 is connected at one end to a forceps outlet port 741 on a front face of the distal portion 732. The other end of the forceps channel 740 is divided into three paths, and connected to the attachment portion 728, the forceps inlet port 729 and the suction valve 730. Upon attachment of the assisting tool 702 to the endoscope 701 through the attachment portion 728 and the forceps inlet port 729, the forceps channels 51, 740 are interconnected.

The suction valve 730 has a port 742, which is connected to a suction device 744 through a tube 743. The suction valve 730 opens as an operating member 745 is manipulated. The suction device 744 is configured in the same manner as the suction device 119 of the first embodiment. The dirt, blood and other body fluids suctioned from the patient' s body are collected in a suction tank 746.

Upon manipulation of the operating member 745 to open the suction valve 730, the suction device 744 performs suctioning either through the forceps channel 740 of the assisting tool 702 alone or through the forceps channels 51, 740 of the endoscope 701 and the assisting tool 702. The forceps inlet port 729 of the assisting tool 702 is used for inserting a medical instrument while the assisting tool 702 is attached to the endoscope 701, and the forceps channels 51, 740 are in use for suctioning. At this point, the forceps inlet port 729 is covered with the detachable stopper 725 that is normally put on the forceps inlet port 717 of the endoscope 701. Additionally, the forceps channel 51 interconnected to the forceps channel 740 can also be connected to the separate suction device 119, so that it can be used independently from the forceps channel 740 for suctioning. In either case, a larger volume of dirt, blob and other body fluids can be suctioned than with the endoscope 701 alone. Further, the medical treatment can be conducted during the examination by inserting a medical instrument through the forceps inlet port 729 of the assisting tool 702.

As shown in FIG. 57, the suction valve 730 has a valve main body 750 and a valve casing 738 to be secured to the proximal portion 738 of the assisting tool 702, and they are dissociable. The valve main body 750 includes the operating member 745, a valve guide shaft 752 as a stem, a valve element 753 and a connecting pipe 754 with the port 742 on the tip. The operating member 745 is an elastic component having a channel-shaped cross section, and includes a head 756, a thin skirt 757 beneath the head 756 and an opening 758 being fastened to the valve main body 750. Upon the press of the head 756, the skirt 757 is folded outward to bring down the head 756. The head 756 is coupled to one end of the valve guide shaft 752. The skirt 757 has an aperture 759 for communicating with the exterior space, and as the head 756 is released, the head 756 returns by itself to the original position. This movement of the head 756 shifts the valve guide shaft 752 between an upper position and a lower position.

Inside the valve main body 750 is formed a channel 760. Inside the valve casing 751 is formed a channel 761, or valve chamber, leading to the forceps channel 740. These channels 760,

761 are interconnected as the valve main body 750 is attached to the valve casing 751.

The valve guide shaft 752 is surrounded and guided by an inner wall of the channel 760 in the valve main body 750, and its leading end is exposed to the channel 761 in the valve casing 751.

The valve element 753 is fastened to the leading end of the valve guide shaft 752. As the valve guide shaft 752 is shifted to the upper position, the valve element 753 moves to a close position where it fits into a small diameter portion 762 in the valve casing 751 to close the channel 761. As the valve guide shaft 752 is shifted to the lower position, the valve element 753 moves to an open position where it projects into a large diameter portion 763 in the valve casing 751, as shown in FIG. 38, to open the channel 761.

The connecting pipe 754 is coupled to the channel 760 in the valve main body 750. The valve guide shaft 752 has a cutout 764 on the shaft surface. As the valve element moves to the open position, this cutout 764 connects the channel 760 of the valve main body 750 to the channel 761 of the valve casing 751. For better handling, the valve main body 750 is configured to rotate the connecting pipe 754 around the channel 760.

Next, with reference to FIG. 59, the operation of the endoscope system 700 is described. The nasal endoscopic examination begins with the previous treatment, and then the insertion section 706 of the endoscope 701 is inserted through one of nostrils. When no lesion or wound to be treated is found in the duodenum and the stomach, the insertion section 706 is pulled out.

If a lesion is found and it seems be treated with the small-diameter forceps channel 51 of the endoscope 701, a compact snare or forceps or such medical instrument is introduced to treat the lesion.

On the other hand, the assisting tool 702 is combined with the endoscope 701 in the case of suctioning the body fluids during the medical treatment or examination, or the case of suctioning a large volume of body fluids .

When combined with the endoscope 701 in use, the assisting tool 702 is connected to the suction device 744 via the port 742, and anesthesia is applied to the other nasal cavity behind the other unoccupied nostril. Then, the insertion section 706 of the endoscope 701 is once pulled back to the area between the posterior nasal aperture and the esophagus, so as to fasten together the insertion sections 706, 727.

Now, the insertion section 727 of the assisting tool 702 is inserted through the other nostril and advanced until the magnets 735, 736 of the assisting tool 702 stick to the magnets 715, 716 of the endoscope 701.

The stoppers 725, 739 are removed from the forceps inlet port 717 of the endoscope 701 and the attachment portion 728 of the assisting tool 702 respectively, and the attachment portion

728 is attached to the forceps inlet port 717. Two forceps channels

51, 740 of the endoscope 701 and the assisting tool 702 are now interconnected, and the proximal portion 738 of the assisting tool

702 can be handled integrally with the handling section 707 of the endoscope 701.

Thereafter, the insertion sections 706, 727 are slowly advanced together to visualize the interior of the patient' s body. Upon finding a lesion or wound on the monitor 705, a medical instrument is inserted through the forceps inlet port 729 of the assisting tool 702 to treatment that affected part.

When it is required to suction dirt, blood and other body fluids during the treatment or examination, the medical instrument is once pulled out. Then, the suction device 744 is activated, and the operating member 745 of the suction valve 730 is pushed to start suctioning.

This combined use of the endoscope 701 and the assisting tool 702 enables the forceps channels 59, 741 to function as two separate suction mouths, and makes it possible to suction a large volume of body fluids in a short time.

Alternatively, the suctioning and the medical treatment can be conducted at the same time. In this case, the suction button 720 is pressed with the medical instrument remaining in the forceps channel 740 of the assisting tool 702, so as to start suctioning through the forceps channel 51 of the endoscope 701.

In this embodiment, the forceps channels 51, 740 are interconnected upon attachment of the assisting tool 702 to the endoscope 701 through the attachment portion 728. The forceps channels 51, 740 need not, however, be interconnected, and the assisting tool 702 may be simply attached to the handling section

707 or the operation section 708.

In this case, as shown in FIG. 60, depressions are formed in the handling part (namely, the handling section 707 or the operation section 708) of the endoscope 701, and corresponding projections are formed in the proximal portion 738 of the assisting tool 702. These projections are inserted in the depressions to join the handling part and the proximal portion 738.

The depressions have grooves 770, 771 on their interior side walls, and the projections have elastic flanges 772, 773 that detachably fit into the grooves 770, 771. The engagement of these grooves 770, 771 and flanges 772, 773 integrates the handling part with the proximal portion 738.

The grooves 770, 771 and the flanges 772, 773 are equally spaced apart in the insertion direction of the insertion sections 706, 727. One of the grooves 770, 771 is used for positioning, while the other is used for anti-rotation. The insertion of the medical instrument and the suctioning are mainly performed with the assisting tool 702 that has the larger diameter forceps channel 740. Instead of the depressions and the projections, any conventional engagement mechanism including an engaging claw and an engaging hole, a magnet and a magnetic body, a coupling band may be used.

The endoscopic image may sometimes appear dark on the monitor 705. In view of this situation, a light guide and a illumination optical system may be provided in the insertion section 727 of the assisting tool 702. As shown in FIG. 61, an assisting tool 780 has an illumination window 781 on a front face 732a of the insertion section 727, and an illumination optical system placed behind the illumination window 781. A light incident plane of the illumination optical system faces a light exit end of a light guide 782. The light guide 782 runs throughout an interior space of the insertion section 727. This light guide 782 further passes through a cord 783 that extends from the proximal portion 738, and reaches the light source device 703 by way of an LG connector 784. The light guide 782 has a light incident end through which the illumination light out of a light source lamp of the light source device 703 enters.

Providing additional illumination light, the assisting tool 780 improves the luminous intensity distribution of the illumination light, and expands the sufficiently illuminated area for the image sensor 63 of the endoscope 701. Since the luminous intensity is increased, the illumination light can reach a distant area. It is therefore possible to enhance the image quality.

Also in this embodiment, it is preferred to attach the proximal portion 738 of the assisting tool 780 to the handling part of the endoscope 701. The assisting tool 780 may be provided with two or more illumination windows 781. Additionally, the assisting tool 780 may be connected to a separate light source device. This light source device may preferably be configured to communicate with the light source device 703, and adjust the illumination light to the same intensity as the illumination light of the light source device 703. Instead of the light guide and the illumination optical system, one or more LEDs and an LED driver may be used.

Various changes and modifications are possible in the present invention and may be understood to be within the present invention.

Claims

1. An endoscope system comprising: an endoscope having a primary insertion section to be inserted into a body cavity through a nostril; and an assisting tool used together with said endoscope, said assisting tool having an auxiliary insertion section to be inserted into said body cavity through the other nostril so as to assist function of said endoscope.

2. The endoscope system of claim 1, wherein said function comprises a function of at least one of a forceps channel, an illuminator, an air feed channel and a water feed channel.

3. The endoscope system of claim 1, wherein said assisting tool has an auxiliary forceps channel extending between proximal and distal ends of said auxiliary insertion section.

4. The endoscope system of claim 1, wherein a proximal end of said assisting tool is provided with an attachment detachably attached to an endoscope operation section that is coupled to a proximal end of said primary insertion section.

5. The endoscope system of claim 4, wherein said endoscope has a primary forceps channel extending between a distal end and said proximal end of said primary insertion section, and a primary forceps inlet port exposed on said operation section and coupled and said primary forceps channel, and wherein said attachment has an auxiliary forceps inlet port coupled to said auxiliary forceps channel, and a connecting channel for connecting said auxiliary forceps channel to said primary forceps inlet port.

6. The endoscope system of claim 1, further comprising a fastening member on either one or both of said primary and auxiliary insertion sections, said fastening member detachably fastening front ends of said primary and auxiliary insertion sections so as to orient front faces of said primary and auxiliary insertion sections in the same direction.

7. The endoscope system of claim 1, wherein said auxiliary insertion section has an illuminator for assisting an illumination function of said endoscope.

8. The endoscope system of claim 7, further comprising: a processing device connected to said endoscope, said processing device generating a video signal and brightness information based on an image signal from an image sensor of said endoscope; and a light source device connected to said processing device and said assisting tool, said light source device having a light source capable of changing luminous intensity based on said brightness information, and wherein said illuminator of said assisting tool includes a light guide passing through an interior space extending between said distal and proximal ends of said auxiliary insertion section, said light guide guiding illumination light from said light source to said proximal end, an illumination lens adjacent to a light exit end of said light guide, and an illumination window for emitting said illumination light having passed through said illumination lens into said body cavity.

9. The endoscope system of claim 7, further comprising an LED controller connected to said assisting tool, and wherein said illuminator of said assisting tool includes at least one white LED whose luminous intensity is adjustable by said LED controller, and an illumination window for emitting the light of said LED into said body cavity.

10. The endoscope system of claim 9, further comprising a processor connected to said endoscope and said LED controller, said processor generating a video signal and brightness information based on an image signal generated by an image sensor of said endoscope, said brightness information being transmitted to said LED controller, and wherein said LED controller adjusts luminous intensity of said LED based on said brightness information.

11. The endoscope system of claim 8, wherein said endoscope further comprises: a light guide passing through an interior space extending between distal and proximal ends of said primary insertion section, said light guide having light entrance and light exit ends: and an auxiliary LG socket connected to a part of said light exit end of said light guide, and wherein said assisting tool has an LG attachment on said proximal end, said LG attachment having an auxiliary LG connector coupled to a light entrance end of said light guide of said assisting tool, said LG attachment detachably attaching said auxiliary LG connector to said auxiliary LG socket and allowing illumination light in said light guide of said endoscope to enter said light guide of said assisting tool.

12. The endoscope system of claim 1, further comprising: a magnet in a front end of one of said primary and auxiliary insertion sections; and a magnetically attractable body in a front end of the other of said primary and auxiliary insertion sections, said magnetically attractable body being attachable to said magnet and fastening together said insertion sections with their front faces being aligned.

13. The endoscope system of claim 12, wherein at least one of said magnet and said magnetically attractable body is elongated in an axial direction of corresponding insertion section so as to allow each of said primary and auxiliary insertion sections to move relatively in said axial direction without separating from each other, and wherein said auxiliary insertion section of said assisting tool is provided with an engaging member for mechanically fastening said front ends of said primary and auxiliary insertion sections together, said engaging member being configured to engage with an engaged member on said primary insertion section as said auxiliary insertion section moves in said axial direction on said primary insertion section.

14. The endoscope system of claim 13, wherein said engaging member and said engaged member align said front faces of said primary and auxiliary insertion sections as they engage with each other to fasten together said front ends.

15. The endoscope system of claim 12, wherein said magnet comprises an electromagnet.

16. The endoscope system of claim 12, further comprising a detector for detecting that said primary and auxiliary insertion sections are fastened together.

17. The endoscope system of claim 1, further comprising a tubular guide member attached parallel to said auxiliary- insertion section, said guide member permitting passage of said primary insertion section and holding said primary insertion section along said auxiliary insertion section.

18. The endoscope system of claim 17, wherein an outer surface of said guide member is formed with at least one access window portion for permitting passage of said primary insertion section.

19. The endoscope system of claim 18, wherein said opening includes a through hole on said outer surface of said guide member, and a guide element for guiding said primary insertion section approaching from a proximal end of said guide member to said through hole .

20. The endoscope system of claim 1, further comprising an adapter for connecting a proximal end of said auxiliary insertion section and a handling part of said endoscope.

21. The endoscope system of claim 20, wherein said adapter includes an endoscope mount attachable to said handling part of said endoscope, and an assisting tool mount attachable to said proximal end of said assisting tool.

22. The endoscope system of claim 21, wherein said endoscope mount has an endoscope port fitting to a primary forceps inlet port that is coupled to a primary forceps channel passing through an interior space extending from a distal end of said primary insertion section to said handling part of said endoscope, and wherein said assisting tool mount has an assisting tool port fitting to an auxiliary forceps inlet port that is coupled to an auxiliary forceps channel passing through an interior space extending between distal and proximal ends of said auxiliary insertion section of said assisting tool, and wherein said adapter has either an adapter-side forceps inlet port to be connected to both said endoscope port and said assisting tool port, or a pair of adapter-side forceps inlet ports to be separately connected to said endoscope port and said assisting tool port.

23. The endoscope system of claim 1, wherein said assisting tool includes a suction channel passing through an interior space extending between a suction mouth on a front face of said auxiliary insertion section and a proximal end of said auxiliary insertion section, a suction valve provided on said proximal end and opening and closing said suction channel, and a port for connecting a suction device to said suction channel as said suction valve opens for suctioning.

24. The endoscope system of claim 23, wherein said suction channel also functions as a forceps channel.

25. A method of using an endoscope system having an endoscope and an assisting tool for assisting function of said endoscope, said method comprising the steps of: inserting a primary insertion section of said endoscope through a nostril, said primary insertion section having an image sensor on its distal end and at least a primary forceps channel passing through an interior space extending between said distal end and a proximal end of said primary insertion section; inserting an auxiliary insertion section of said assisting tool through the other nostril, said auxiliary insertion section having an auxiliary forceps channel with larger diameter than said primary forceps channel and extending between distal and proximal ends of said auxiliary insertion section; detachably fastening front ends of said primary and auxiliary insertion sections together while aligning their front faces within an area between posterior nasal aperture and esophagus by using a fastening member provided in one of said front ends of said assisting tool and said endoscope; and before or after said insertion step of said auxiliary insertion section or after said fastening step, detachably attaching said proximal end of said auxiliary insertion section to a handling part of said endoscope, said handling part being coupled to said proximal end of said primary insertion section.

26. An assisting tool used together with an endoscope having a primary insertion section to be inserted into a body cavity through a nostril, comprising: an auxiliary insertion section to be inserted into said body cavity through the other nostril so as to assist function of said endoscope.

27. The assisting tool of claim 26, further comprising a fastening member for detachably fastening front ends of said primary and auxiliary insertion sections together with their front faces being aligned.

28. The assisting tool of claim 27, wherein said fastening member includes an annular retainer for permitting passage of said primary insertion section of said endoscope so as to fasten said primary and auxiliary insertion sections together.

29. The assisting tool of claim 28, wherein said retainer comprises a ring-shaped or sleeve-shaped balloon that expands upon inflation of fluid and shrinks upon suction of said fluid, said balloon changing its inner diameter upon expansion and shrinkage so as to hold or release said primary insertion section.

30. The assisting tool of claim 28, wherein said retainer comprises a loop of string translatable between a retracted position into a restraint channel passing through said auxiliary insertion section and a projected position out of said restraint channel, said loop of string changing its projection length out of said restraint channel so as to hold or release said primary insertion section.

31. The assisting tool of claim 30, wherein said loop of string is made of an elastic wire that is previously shaped to expand to a loop upon projecting from said restraint channel.

32. An adapter for connecting an endoscope having a long slender primary insertion section to be inserted into a body cavity through a nostril and an assisting tool having a long slender auxiliary insertion section to be inserted into said body cavity through the other nostril so as to assist function of said endoscope, said adapter comprising: an endoscope mount attachable to a handling part coupled to a proximal end of said primary insertion section; and an assisting tool mount attachable to a proximal end of said auxiliary insertion section.