JP4647972B2 - Endoscope shape detection device - Google Patents

Description

  The present invention relates to an endoscope shape detecting apparatus that detects and displays an insertion shape of an endoscope using a magnetic field generating element and a magnetic field detecting element.

  2. Description of the Related Art In recent years, an endoscope shape detecting apparatus that detects the shape of an endoscope inserted into a body or the like using a magnetic field generating element and a magnetic field detecting element and performs display by a display means has come to be used.

  For example, Japanese Patent Application Laid-Open No. 2003-290129 discloses an apparatus that detects an endoscope shape using a magnetic field and displays the detected endoscope shape. Then, a plurality of magnetic field generating elements arranged at predetermined intervals in the insertion portion of the endoscope inserted into the body are driven to generate a magnetic field around the elements, and each magnetic field generating element is arranged by a magnetic field detecting element arranged outside the body. A three-dimensional position is detected, a curve continuously connecting the magnetic field generating elements is generated, and a modeled three-dimensional image of the insertion portion is displayed on the display means.

By observing the image, the surgeon or the like can grasp the position of the distal end portion of the insertion portion inserted into the body, the insertion shape, and the like, and can smoothly perform the insertion operation to the target site.
JP 2003-290129 A

  However, in the endoscope shape detection apparatus disclosed in Japanese Patent Laid-Open No. 2003-290129, a sine wave is generated by an oscillator and amplified by an amplifier, a sine wave current is caused to flow through the coil, and an alternating magnetic field is generated (driven). However, because the gain of the amplifier is fixed, proper driving cannot be performed if the type of coil changes.

  That is, a large coil is used for a thick endoscope, and a small coil is used for a thin endoscope, and lead wire lengths and the like are also different (the length of the insertion portion of the endoscope, the material → thin, so that the direct current resistance is high. Can not be ignored when driving). As a result, when the type of the coil changes, the impedance changes. For example, the current is too large and the coil can be burned, or the current is too small and only a weak magnetic field can be generated.

  These problems can be solved by changing the processing steps or data depending on the coil to be used. However, since the type of coil to be arranged differs every time the endoscope used is changed, software is frequently used. Or you need to update the data.

  The present invention has been made in view of the above circumstances, and provides an endoscope shape detection device that can easily perform shape detection and estimation using optimal coil data without updating software or data. The purpose is that.

An endoscope shape detection device according to the present invention has one of a plurality of magnetic field generating elements and a plurality of magnetic field detection elements arranged inside an insertion portion of an endoscope that is inserted into a subject, and is provided outside the subject. The other element is arranged, and a detecting means for detecting each position of one element arranged inside the insertion portion using the position of the other element as a reference, and controlling the detecting means, The shape of the endoscope insertion portion is estimated , information on the arrangement of the magnetic field generating elements is read for each endoscope inserted into the subject, and the detection result of the detection means and the information on the arrangement are used. And a shape estimating means for estimating the shape of the endoscope insertion portion .

  According to the present invention, there is an effect that shape detection and estimation can be easily performed using optimum coil data without updating software or data.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 to 15 relate to a first embodiment of the present invention, FIG. 1 is a configuration diagram showing a configuration of an endoscope system, and FIG. 2 is a diagram showing an arrangement example of coils built in the coil unit of FIG. 3 is a block diagram showing the configuration of the endoscope shape detection device of FIG. 1, FIG. 4 is a diagram showing the configuration of the reception block and the control block of FIG. 3, and FIG. 5 is a diagram showing the detailed configuration of the reception block of FIG. 6 is a timing diagram showing the operation of the 2-port memory and the like of FIG. 4, FIG. 7 is a diagram showing the configuration of the electronic endoscope of FIG. 1, and FIG. 8 is a diagram showing a memory map of the second RAM of FIG. 9 is a diagram showing the configuration of the coil drive unit of the source coil drive circuit unit of FIG. 4, FIG. 10 is a flowchart for explaining the operation of the endoscope system of FIG. 3, and FIG. 11 is a flowchart of the coil drive unit of FIG. FIG. 12 is a diagram illustrating a first modification, FIG. 12 is a diagram illustrating a second modification of the coil driving unit in FIG. Is a diagram showing a modification of the memory map of the second RAM in FIG. 5, FIG. 14 is a diagram for explaining a modification of data stored in the second RAM in FIG. 5, and FIG. 15 is an endoscope system in FIG. FIG.

  As shown in FIG. 1, the endoscope system 1 in the present embodiment includes an endoscope apparatus 2 that performs an endoscopic examination, and an endoscope shape detection apparatus 3 that is used to assist the endoscopic examination. The endoscope shape detection device 3 is used as an insertion assisting means when performing an endoscopic examination by inserting the insertion portion 7 of the electronic endoscope 6 into the body cavity of the patient 5 lying on the bed 4.

  The electronic endoscope 6 is formed with an operation portion 8 provided with a bending operation knob at the rear end of the elongated insertion portion 7 having flexibility, and a universal cord 9 is extended from the operation portion 8 so that a video imaging system is provided. (Or video processor) 10.

  This electronic endoscope 6 is inserted with a light guide, transmits illumination light from the light source section in the video processor 10, emits illumination light transmitted from an illumination window provided at the distal end of the insertion section 7, and removes the patient and the like. Illuminate. An illuminated object such as an affected part is connected to an image sensor (CCD) disposed at the image formation position by an objective lens attached to an observation window provided adjacent to the illumination window, and this image sensor is photoelectrically converted. To do.

  The photoelectrically converted signal is subjected to signal processing by a video signal processing unit in the video processor 10 to generate a standard video signal, which is displayed on an image observation monitor 11 connected to the video processor 10.

  The electronic endoscope 6 is provided with a forceps channel 12, for example, 16 magnetic field generating elements (or source coils) 14 a, 14 b,..., 14 p (hereinafter, denoted by reference numeral 14 i) from the insertion opening 12 a of the forceps channel 12. The source coil 14 i is installed in the insertion portion 7 by inserting the probe 15 having a representative).

  The source cable 16 extended from the rear end of the probe 15 has a rear end connector 16a detachably connected to a detection device (also referred to as a device main body) 21 as a device main body of the endoscope shape detection device 3. . Then, a high frequency signal (drive signal) is applied from the detection device 21 side to the source coil 14i serving as the magnetic field generating means via the source cable 16 as the high frequency signal transmitting means, so that the source coil 14i transmits the electromagnetic wave accompanied by the magnetic field around. Radiate.

  The detection device 21 disposed near the bed 4 on which the patient 5 lies is provided with a (sense) coil unit 23 that can move up and down in the vertical direction. The detection element (sense coil) is arranged (more specifically, as shown in FIG. 2, for example, the sense coil 22a-1 that faces the X axis, for example, the center Z coordinate is the first Z coordinate, 22a-2, 22a-3, 22a-4, and the sense coils 22b-1, 22b-2, 22b-3 facing the Y axis, which is the second Z coordinate whose Z coordinate is different from the first Z coordinate , 22b-4, and the sense coils 22c-1, 22c-2, 22c-3, 22c-4 facing the Z axis, which is a third Z coordinate whose center Z coordinate is different from the first and second Z coordinates Twelve sense coils (hereinafter referred to as symbols) Representing at 2j) are arranged).

  The sense coil 22j is connected to the detection device 21 via a cable (not shown) from the coil unit 23. The detection device 21 is provided with an operation panel 24 for a user to operate the device. In addition, a liquid crystal monitor 25 is disposed on the detection device 21 as display means for displaying the detected shape of the endoscope insertion portion (hereinafter referred to as a scope model).

  As shown in FIG. 3, the endoscope shape detection device 3 includes a transmission block 26 that drives the source coil 14 i, a reception block 27 that receives a signal received by the sense coil 22 j in the coil unit 23, and a reception block 27. And a control block 28 that performs signal processing on the signal detected in (1).

  As shown in FIG. 4, the probe 15 installed in the insertion portion 7 of the electronic endoscope 6 has 16 source coils 14i for generating a magnetic field arranged at predetermined intervals as described above. These source coils 14 i are connected to a source coil drive circuit 31 that generates 16 drive signals having different frequencies constituting the transmission block 26.

  The source coil drive circuit unit 31 drives each source coil 14i with a sinusoidal drive signal having a different frequency, and each drive frequency is a drive frequency setting data storage means (not shown) or a drive frequency inside the source coil drive circuit unit 31. It is set by drive frequency setting data (also referred to as drive frequency data) stored in the setting data storage means. This drive frequency data is obtained from a source coil drive circuit unit 31 via a PIO (parallel input / output circuit) 33 by a CPU (central processing unit) 32 which is a shape estimation means for performing an endoscope shape calculation process in the control block 28. Is stored in a drive frequency data storage means (not shown).

  On the other hand, twelve sense coils 22 j in the coil unit 23 are connected to a sense coil signal amplification circuit unit 34 that constitutes a reception block 27.

In the sense coil signal amplifying circuit section 34, as shown in FIG. 5, twelve single core coils 22k constituting the sense coil 22j are respectively connected to the amplifying circuit 35k and 12 processing systems are provided. After a minute signal detected by the heart coil 22k is amplified by the amplifier circuit 35k, the filter circuit 36k has a band through which a plurality of frequencies generated by the source coil group passes, and unnecessary components are removed and output to the output buffer 37k. An ADC (analog / digital converter) 38k converts the control block 28 into a readable digital signal.
The reception block 27 includes a sense coil signal amplification circuit unit 34 and an ADC 38k. The sense coil signal amplification circuit unit 34 includes an amplification circuit 35k, a filter circuit 36k, and an output buffer 37k.

  Returning to FIG. 4, the 12 outputs of the sense coil signal amplifying circuit unit 34 are transmitted to the 12 ADCs 38 k and supplied from the control signal generating circuit unit 40 as numerical data writing means in the control block 28. It is converted into digital data having a predetermined sampling period by a clock. This digital data is written into a 2-port memory 42 as data output means via a local data bus 41 by a control signal from the control signal generation circuit unit 40.

  As shown in FIG. 5, the 2-port memory 42 is functionally composed of a local controller 42a, a first RAM 42b, a second RAM 42c, and a bus switch 42d. The ADC 38k starts A / D conversion by the A / D conversion start signal from the controller 42a, and the bus switch 42d alternately reads the first RAMs 42b and 42c while switching the RAMs 42b and 42c by the switching signal from the local controller 42a. Used as a memory, data is always taken in after a power-on by a write signal.

  Returning to FIG. 4 again, the CPU 32 transfers the digital data written in the 2-port memory 42 by the control signal from the control signal generation circuit 40 from the local data bus 43, the PCI controller 44 and the PCI bus 45 (see FIG. 5). Is read out via the internal bus 46, and the main memory 47 is used to perform frequency extraction processing (Fast Fourier Transform: FFT) on the digital data, and the magnetic field detection information of the frequency component corresponding to the driving frequency of each source coil 14i. And the spatial position coordinates of each source coil 14i provided in the insertion portion 7 of the electronic endoscope 6 is calculated from each digital data of the separated magnetic field detection information.

  In addition, the insertion state of the insertion unit 7 of the electronic endoscope 6 is estimated from the calculated position coordinate data, display data forming a scope model is generated, and output to the video RAM 48. The data written in the video RAM 48 is read by the video signal generation circuit 49, converted into an analog video signal, and output to the liquid crystal monitor 25. When this analog video signal is input, the liquid crystal monitor 25 displays the scope model of the insertion portion 7 of the electronic endoscope 6 on the display screen.

  In the CPU 32, magnetic field detection information corresponding to each source coil 14i, that is, electromotive force (amplitude value of a sine wave signal) generated in the single-core coil 22k constituting each sense coil 22j and phase information are calculated. The phase information indicates the polarity ± of the electromotive force.

  In this embodiment, as shown in FIG. 1, the detection device 21 has an extracorporeal marker 57 for displaying the position outside the body in order to confirm the position of the insertion portion 7 inserted into the body. Even if the posture of the patient 5 is changed by attaching it to the abdomen of the patient 5 or the like, the reference plate 58 used for always displaying the scope model from a specific direction (of the patient 5) is provided on the detection device 21. It can also be used by connecting.

  The extracorporeal marker 57 accommodates one source coil therein, and the connector 59a at the base end of the cable 59 of the extracorporeal marker 57 is detachably connected to the detection device 21.

  By connecting this connector 59a, the source coil of the extracorporeal marker 57 is driven in the same manner as the source coil in the probe 15, and the position of the source coil of the extracorporeal marker 57 detected by the coil unit 23 is also the scope model. Is displayed on the monitor 25 in the same manner.

  The reference plate 58 includes, for example, three source coils on the disk surface inside the disk-shaped portion, and a connector 60a at the base end of the cable 60 connected to the three source coils is a detection device. 21 is detachably connected.

  By detecting the positions of these three source coils, the surface on which they are arranged is determined. Then, it is used to draw a scope model so as to be a scope model observed when the insertion portion 7 is viewed from a direction perpendicular to the surface.

  As shown in FIG. 4, in this embodiment, the connector 21a, 21b, 21c to which the connector 16a of the probe 15, the connector 59a of the extracorporeal marker 57, and the connector 60a of the reference plate 58 are connected to the detection device 21, respectively. The connector receivers 21 a, 21 b, and 21 c are connected to the source coil drive circuit 31.

  As shown in FIG. 7, in the electronic endoscope 6, a light guide 100 that transmits illumination light and a probe 15 having a plurality of source coils 14 i are disposed in the insertion portion 7, and in the distal end portion of the insertion portion 7. Is provided with a CCD 101 for imaging a subject. Then, the CCD 101 is driven by the drive signal from the video processor 10, and the image signal picked up by the CCD 101 is transmitted to the video processor 10 through the buffer circuit 102. The drive signal and the imaging signal are transmitted and received between the video processor 10 and the CCD 101 through a signal cable 99 for inserting the insertion unit 7.

  On the other hand, the operation unit 102 on the proximal end side of the electronic endoscope 6 is provided with a non-volatile memory 103, and this non-volatile memory 103 is provided with the probe 15 which is calculation / setting numerical data. Stored is gain setting data of a drive signal used when driving the source coil 14i.

  The gain setting data (calculation / setting numerical data) is taken into the endoscope shape detection device 3 via the video processor 10 when the endoscope system 1 is activated. In the endoscope shape detecting device 3, the gain setting data (calculation / setting numerical data) is transmitted through the control signal generating circuit unit 40 (numerical data writing means), for example, as shown in FIG. 2 is stored in a predetermined address area of the RAM 42c (see FIG. 4).

  As shown in FIG. 9, the source coil drive circuit unit 31 of the endoscope shape detection device 3 includes an oscillator 110 that generates a sine wave, and a GCA that amplifies the sine wave and generates (drives) an AC magnetic field in the source coil. (Gain control amplifier) 111 and a plurality of coil driving units 113 including a data conversion unit 112 that converts gain setting data (calculation / setting numerical data) into 8-bit serial data. The plurality of source coils 14i are driven by setting the gain of the GCA 111 by the serial gain setting data.

  The endoscope shape detection process in the present embodiment configured as described above will be described.

  When the endoscope system 1 is activated, the CPU 32 of the endoscope shape detection apparatus 3 gains a gain from the nonvolatile memory 103 of the electronic endoscope 6 in step S1, as shown in FIG. Setting data (calculation / setting numerical data) is read, and gain setting data (calculation / setting numerical data) is transmitted to the endoscope shape detection device 3.

  In step S <b> 2, the CPU 32 of the endoscope shape detection device 3 sends the gain setting data (calculation / setting numerical data) to the predetermined RAM of the second RAM 42 c of the 2-port memory 42 via the control signal generation circuit unit 40. Store in the address area (see FIG. 8).

  For example, when the gain setting value of the GCA 111 is “11001000” as the driving condition of the source coil of the probe 15 arranged in the electronic endoscope 6, this data “11001000” is the gain setting data (calculation / setting numerical data). ) Is stored in the non-volatile memory 103, and data “11001000” is written to a predetermined address area of the second RAM 42 c of the 2-port memory 42.

  At this time, since the default gain setting data or the gain setting data of the electronic endoscope 6 when the endoscope system 1 was used last time is stored in the predetermined address area, the CPU 32 has a predetermined address. Processing to rewrite the data in the area is performed, and gain setting data (calculation / setting numerical data) is stored.

  Next, in step S3, gain setting data (calculation / setting numerical data) is read out from a predetermined address area of the second RAM 42c and output to the source coil drive circuit unit 31 (see FIG. 9). Thereby, in the source coil drive circuit unit 31, gain setting data (calculation / setting numerical value data) is converted into serial gain setting data by the data conversion unit 112, and the gain of the GCA 111 is arranged in the electronic endoscope 6. 15 is set to a set value.

  In step S4, the source coil is driven to detect the endoscope shape, the detected endoscope shape is displayed on the liquid crystal monitor 25, and the process is terminated.

  As described above, in the endoscope shape detection device 3 according to the present embodiment, gain setting data which is calculation / setting numerical data corresponding to the source coil of the probe 15 arranged in the electronic endoscope 6 is obtained from the electronic endoscope 6. Stored in a predetermined address area of the second RAM 42c of the 2-port memory 42 from the non-volatile memory 103 via the video processor 10, and the gain of the GCA 111 is directly set using this gain setting data. Every 15th, the source coil can be easily driven under optimum driving conditions without updating the software or data table.

  Although the gain of the GCA 111 is set using the gain setting data, the present invention is not limited to this. For example, as shown in FIG. 11, the gain is set by switching the oscillator 110 that generates a sine wave and a plurality of feedback resistors. The coil driving unit 113 may be configured by the operational amplifier 121 and the data conversion unit 122 that converts the gain setting data into parallel data for setting the feedback resistance of the operational amplifier 121. As shown in FIG. May be configured by the digital potentiometer 131, and the coil driving unit 113 may be configured by providing a data conversion unit 132 that converts the gain setting data into a control signal of the digital potentiometer 131.

  In this embodiment, the gain setting data is described as an example of the calculation / setting numerical data. However, the present invention is not limited to this. For example, the number of source coils arranged in the probe 15 and the coil interval are electronically calculated / set numerical data. The data is stored in the nonvolatile memory 103 of the endoscope 6 and data indicating the number of source coils and the coil interval are written in a predetermined address area of the second RAM 42c of the 2-port memory 42 as shown in FIG. Also good.

  There are various types of endoscopes, and some have different insertion lengths. Longer ones have more coils and shorter ones have fewer. For example, in the endoscope shape detection apparatus disclosed in Japanese Patent Application Laid-Open No. 2000-93986, the interval between the coils is narrow in the bending portion and is widely arranged in the soft portion.

  Moreover, in the endoscope shape detection apparatus of Unexamined-Japanese-Patent No. 2003-2445293986, when drawing an endoscope shape, an interpolation process is performed and the smooth shape is drawn. This processing requires the coil interval and the number of coils.

  Some have two curved portions as disclosed in JP-A-2001-231743.

  Therefore, in the nonvolatile memory 103 of the endoscope 6, as shown in FIG. 14, for example, the number of source coils is 10 and the coil interval is 5 cm from the distal end of the endoscope to the fifth coil, and the tenth from the fifth coil. When the distance to the coil is 10 cm, "10, 5, 5, 5, 5, 5, 10, 10, 10, 10, 10" is encoded and stored as operation / setting numerical data, as shown in FIG. By writing data indicating the number of source coils and the coil interval in a predetermined address area of the second RAM 42c of the two-port memory 42, the endoscope shape detection apparatus draws a shape using the data. May be.

  In this embodiment, the endoscope shape detection apparatus 3 takes in the arithmetic / setting numerical data stored in the nonvolatile memory 103 of the electronic endoscope 6 via the video processor 10, but the present invention is not limited to this. Instead, the endoscope shape detection device 3 may directly acquire calculation / setting numerical data stored in the nonvolatile memory 103 of the electronic endoscope 6.

  Further, when the calculation / setting numerical data stored in the nonvolatile memory 103 of the electronic endoscope 6 is stored in a separate memory card (not shown) and the electronic endoscope is used, FIG. As shown in the figure, a memory card may be inserted into a slot 151 provided in the endoscope shape detecting device to read calculation / setting numerical data, and even in an electronic endoscope having no nonvolatile memory 103, this embodiment The calculation / setting numerical value data can be taken in by the slot 151 without using the video processor 10.

  The present invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the scope of the present invention.

1 is a configuration diagram showing the configuration of an endoscope system according to Embodiment 1 of the present invention. The figure which shows the example of arrangement | positioning of the coil incorporated in the coil unit of FIG. The block diagram which shows the structure of the endoscope shape detection apparatus of FIG. The figure which shows the structure of the receiving block and control block of FIG. The figure which shows the detailed structure of the receiving block of FIG. Timing chart showing the operation of the 2-port memory of FIG. The figure which shows the structure of the electronic endoscope of FIG. The figure which shows the memory map of 2nd RAM of FIG. The figure which shows the structure of the coil drive part of the source coil drive circuit part of FIG. The flowchart explaining the effect | action of the endoscope system of FIG. The figure which shows the 1st modification of the coil drive part of FIG. The figure which shows the 2nd modification of the coil drive part of FIG. The figure which shows the modification of the memory map of 2nd RAM of FIG. The figure explaining the modification of the data stored in 2nd RAM of FIG. The figure which shows the modification of the endoscope system of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Endoscope system 2 ... Endoscope apparatus 3 ... Endoscope shape detection apparatus 4 ... Bed 5 ... Patient 6 ... Electronic endoscope 7 ... Insertion part 8 ... Operation part 10 ... Video processor 12 ... Forceps channel 14i ... Source coil 15 ... Probe 16 ... Cable 21 ... Detection device 23 ... Coil unit 22j ... Sense coil 24 ... Operation panel 26 ... Transmission block 27 ... Reception block 28 ... Control block 31 ... Source coil drive circuit 32 ... CPU
42 ... 2-port memory 42a ... Local controller 42b ... First RAM
42c ... second RAM
42d ... bus switch 100 ... light guide 101 ... CCD
102 ... Buffer circuit 103 ... Non-volatile memory 110 ... Oscillator 111 ... GCA
112 ... Data conversion unit 113 ... Coil drive unit Agent Patent attorney Susumu Ito

Claims (2)

One of a plurality of magnetic field generating elements and a plurality of magnetic field detecting elements is arranged inside an insertion portion of an endoscope to be inserted into a subject, and the other element is arranged outside the subject, and the insertion portion Detecting means for detecting each position of one of the elements arranged in the inside using the position of the other element as a reference;
Controls the detection means and estimates the shape of the endoscope insertion portion , reads out information on the arrangement of the magnetic field generating elements for each endoscope inserted into the subject, An endoscope shape detection apparatus comprising: a shape estimation unit that estimates a shape of the endoscope insertion portion based on a detection result and information on the arrangement. The shape estimation unit estimates the shape based on information on the number and interval of the magnetic field generating elements read from a storage unit provided in the endoscope. The endoscope shape detection apparatus described.

Images