JP7523762B2 - Irrigation fluid supply system and method of operating the same - Google Patents

Description

The present disclosure relates to an irrigation fluid supply system that delivers irrigation fluid or gas to a surgical site during endoscopic surgery, and more particularly to an irrigation fluid supply system for use in upper urinary tract endoscopic surgery and a method of operating the irrigation fluid supply system .

In the medical field, endoscopic surgery, which involves inserting an endoscope into a body cavity through a hole formed on the patient's skin surface, is becoming more common in order to make surgery less invasive. In the treatment of urological diseases, upper urinary tract endoscopic surgery is performed using a pyeloscope to remove urothelial tumors and urolithiasis in the upper urinary tract (ureter and renal pelvis). In this upper urinary tract endoscopic surgery, an endoscope is inserted into the upper urinary tract from the urethra via the bladder and ureter, and the tip of the endoscope is inserted into the renal pelvis to form a pyeloscope, and the target area is treated with a resection probe while observing the surgical site. Alternatively, an access sheath is inserted into the upper urinary tract from the urethra via the bladder and ureter, and the tip of the endoscope is inserted into the renal pelvis through the access sheath. At this time, the view inside the renal pelvis may be reduced due to stone fragments or bleeding from the surgical site. For this reason, in upper urinary tract endoscopic surgery, a method is used in which perfusion fluid is supplied to the surgical site using a perfusion device that can be set to drip by gravity or at a constant flow rate, ensuring visibility of the surgical site through an endoscope (for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 62-217952 Registered Utility Model No. 3207495

However, in upper urinary tract endoscopic surgery, when there is a large amount of bleeding from the surgical site or when the supply of irrigation fluid is insufficient, it is sometimes impossible to ensure a sufficient field of view using the established method, and measures have been taken to improve visibility by intermittently supplying irrigation fluid. In such cases, there is concern that postoperative complications such as sepsis due to high intrapelvic pressure may occur. Therefore, in order to prevent postoperative complications, upper urinary tract endoscopic surgery requires the supply of irrigation fluid at a constant flow rate to ensure a clear field of view while maintaining low intrapelvic pressure.

The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a perfusion fluid supply system and a method for operating a perfusion fluid supply system that detects intrapelvic pressure during upper urinary tract endoscopic surgery, and supplies a constant flow rate to ensure visibility while maintaining the intrapelvic pressure at a set low intrapelvic pressure when perfusion fluid is supplied.

In order to achieve the above object, a perfusion fluid supply system according to one aspect of the present disclosure is a perfusion fluid supply system for use in endoscopic surgery, comprising an endoscope to be inserted into a body cavity, a fluid supply channel extending within the endoscope to the vicinity of a tip of the endoscope, a pressure sensor extending within the endoscope and detecting a pressure in the vicinity of the tip of the endoscope, a temperature sensor extending within the endoscope and detecting a temperature in the vicinity of the tip of the endoscope, a perfusion pump connected to the fluid supply channel, supplying fluid to the vicinity of the tip of the endoscope through the fluid supply channel and discharging the supplied fluid to the outside of the body through the body cavity, and the pressure sensor and and a control unit electrically connected to the perfusion pump and controlling the supply pressure of perfusion fluid in the perfusion pump based on a pressure signal acquired from the pressure sensor and a temperature signal acquired from the temperature sensor, wherein the control unit corrects the time change in the pressure value indicated by the pressure signal during a pressurization period , which gradually decreases as the supply amount of fluid supplied to the vicinity of the tip of the endoscope increases, based on the temperature signal, and controls the supply amount of perfusion fluid from the perfusion pump by increasing or decreasing the supply pressure of the perfusion fluid in the perfusion pump so that the corrected pressure value approaches a predetermined reference value.

According to the perfusion fluid supply system and the operation method of the perfusion fluid supply system of one aspect of the present disclosure, the intrapelvic pressure can be detected during surgery and the intrapelvic pressure during the supply of perfusion fluid can be brought close to a set reference value. As a result, the intrapelvic pressure during the supply of perfusion fluid can be kept at a low intrapelvic pressure adaptively set for the patient, while a constant flow rate can be supplied to ensure visibility.

1 is a schematic diagram showing the configuration of a perfusion fluid supply system 1 according to embodiment 1. FIG. 1 is an exploded oblique view of the vicinity of the tip of an endoscope 20 in an irrigation fluid supply system 1. FIG. 1A is a schematic diagram showing an outline of the configuration of a pressure sensor 30, and FIG. 1B is an enlarged view of a portion A in FIG. 3A and 3B are schematic diagrams for explaining the principle of pressure measurement in the pressure sensor 30. FIG. 1A shows an access sheath used in a performance evaluation test of the irrigation fluid supply system 1, and FIG. 1B shows the configuration of the endoscope. 13 is an experimental result showing the relationship between the supply pressure and the renal pelvic pressure in the perfusion fluid supply system 1. 13 is an experimental result showing the relationship between the supply pressure and the amount of perfusion fluid supplied in the perfusion fluid supply system 1. 13 is an experimental result showing the change over time in renal pelvic pressure accompanying the supply of perfusion fluid in the perfusion fluid supply system 1. 13 shows the measurement results of intrapelvic pressure during feedback control of intrapelvic pressure using the pressure sensor 30 in the supply of perfusion fluid by the perfusion fluid supply system 1, where (a) shows the result when the pressure is increased and (b) shows the result when the pressure is decreased. A schematic diagram showing the configuration of a perfusion fluid supply system 1A relating to variant example 1. A schematic diagram showing the configuration of a perfusion fluid supply system 1B relating to embodiment 2. 1 is an exploded oblique view of the vicinity of the tip of an endoscope 20 in an irrigation fluid supply system 1B. FIG. These are the results of measuring the change in temperature over time associated with laser irradiation during upper urinary tract endoscopic surgery using a 12/14 Fr access sheath. These are the results of measuring the change in temperature over time associated with laser irradiation during upper urinary tract endoscopic surgery using a 10/12 Fr access sheath. FIG. 1 is a schematic diagram showing a target area for upper urinary tract endoscopic surgery. 13A and 13B are schematic diagrams for explaining the effect of changes in renal pelvic pressure due to the supply of irrigation fluid in upper urinary tract endoscopic surgery.

<<How the invention was developed>>
In the treatment of urological diseases, upper urinary tract endoscopic surgery is performed using a nephroureteroscope to remove or crush tumors or stones in the upper urinary tract (ureter, renal pelvis). Fig. 15 is a schematic diagram showing the target site of upper urinary tract endoscopic surgery. The upper urinary tract refers to the ureter or renal pelvis, and when a stone or tumor is present in the ureter or renal pelvis, the target site is removed or crushed by upper urinary tract endoscopic surgery using a nephroureteroscope.

A nephroscope is constructed by inserting an endoscope into an access sheath, which is a flexible plastic tube. The endoscope has an image acquisition means at the tip and is constructed from a flexible tube with insertion paths for fluids, forceps, laser scalpels, and other surgical tools.

In upper urinary tract endoscopic surgery, an access sheath is inserted from the urethra through the bladder and ureter into the upper urinary tract, and the tip of the endoscope is inserted into the renal pelvis to form a pyeloscope. The surgical site is then observed while a resection probe is used to perform treatment on the target area.

At this time, bleeding from the surgical site causes a problem of reduced visibility inside the ureter or renal pelvis. For this reason, in upper urinary tract endoscopic surgery, a perfusion device that can drip by gravity or be set to a constant flow rate is used to supply perfusion fluid to the surgical site, improving visibility of the surgical site through the endoscope. A continuous perfusion device, for example, has an inlet at the rear of the endoscope, a fluid delivery pump is connected to the inlet to form a fluid delivery channel within the endoscope, and the perfusion fluid is supplied to the living body through the fluid delivery channel using the perfusion pump, and is perfused by draining it outside the body through a drainage path separate from the fluid delivery channel.

However, in upper urinary tract endoscopic surgery, there are cases where a sufficient field of view cannot be obtained using conventional methods, such as when there is a large amount of bleeding from the surgical site or when the supply of irrigation fluid is insufficient. In such cases, in order to improve the visibility of the endoscope in the body cavity using a continuous irrigation device, measures are taken to improve visibility by increasing the irrigation pressure and flow discharged by the fluid delivery pump into the body cavity and intermittently supplying irrigation fluid at a flow rate of up to 5 cc per time.

However, the intrapelvic pressure associated with perfusion generally needs to be controlled within a range of 30 to 40 cmH ₂ O, but varies depending on surgical conditions such as the diameter of the patient's ureter, the size of the renal pelvis, the diameter of the fluid delivery channel, and the supply pressure of the fluid delivery pump. Therefore, if the supply pressure of the fluid delivery pump is increased and the intrapelvic pressure becomes too high, the irrigated bacteriuria or bacteria attached to stones, etc. will invade the kidney from the renal pelvis and flow back into the blood vessels via the collecting duct, raising concerns about the occurrence of postoperative complications such as sepsis associated with high intrapelvic pressure.

Figures 16(a) and (b) are schematic diagrams for explaining the effect of changes in renal pelvic pressure due to the supply of irrigation fluid during upper urinary tract endoscopic surgery. The inner diameter of the access sheath inserted into the ureter is generally 3.17 mm to 5.33 mm (9.5 Fr to 16 Fr) and is selected according to the diameter of the patient's ureter. Figure 16(a) is an example of the use of a small-diameter access sheath, and (b) is an example of the use of a large-diameter access sheath.

As shown in Figure 16 (a), when a small-diameter access sheath is used, the possibility of ureteral damage due to the insertion of the access sheath is low. However, since the perfusion fluid supplied to the renal pelvis is discharged through the gap between the inner wall of the access sheath and the endoscope as a drainage path, when the access sheath is small in diameter, the capacity of the drainage path is reduced and the amount of perfusion fluid discharged is reduced. As a result, the intrapelvic pressure increases, and bacteria attached to the crushed stones, etc. may invade the kidney, causing postoperative complications such as fever, urinary tract infection, and sepsis.

On the other hand, as shown in FIG. 16(b), when a large-diameter access sheath is used, the gap between the inner wall of the access sheath and the endoscope can provide a sufficient drainage path capacity, and the irrigation fluid supplied to the renal pelvis is sufficiently drained. As a result, intrapelvic pressure does not increase, and there is little possibility of postoperative complications such as sepsis occurring. However, there is a risk that the ureter may be damaged during insertion of the access sheath, leading to ureteral damage such as ureteral perforation, which may then lead to the loss of renal function due to ureteral stenosis.

In contrast, in upper urinary tract endoscopic surgery, it is considered necessary to set the irrigation fluid supply pressure to suit the patient's organs and surgical conditions from the standpoint of ensuring a clear view during surgery and preventing postoperative complications.

The inventors therefore conducted extensive research into a method of supplying perfusion fluid that detects intrapelvic pressure during surgery, maintains a low intrapelvic pressure that is adaptively set for the patient, and supplies a constant flow rate to ensure visibility, resulting in the following embodiment.

<Overview of the embodiment of the present invention>
A perfusion fluid supply system according to an embodiment of the present disclosure is a perfusion fluid supply system for use in endoscopic surgery, comprising: an endoscope to be inserted into a body cavity, a fluid supply channel extending within the endoscope to a vicinity of a tip of the endoscope, a pressure sensor extending within the endoscope and detecting a pressure in the vicinity of the tip of the endoscope, a perfusion pump connected to the fluid supply channel, supplying fluid to the vicinity of the tip of the endoscope through the fluid supply channel and discharging the supplied fluid to the outside of the body through the body cavity, and a control unit electrically connected to the pressure sensor and the perfusion pump and controlling a supply pressure of the perfusion fluid in the perfusion pump based on a pressure signal acquired from the pressure sensor. In another aspect, in any of the above aspects, the control unit may be configured to increase or decrease the supply pressure of the perfusion fluid in the perfusion pump so that the pressure value indicated by the pressure signal approaches a predetermined reference value.

This configuration makes it possible to detect the pressure near the tip of the endoscope during surgery and bring the internal pressure in the body cavity closer to a set reference value. As a result, it is possible to supply a constant flow rate to ensure visibility while maintaining the internal pressure in the body cavity when supplying irrigation fluid at a low internal pressure that is adaptively set for the patient.

In another aspect, any of the above aspects may further include a temperature sensor extending into the endoscope for detecting the temperature near the tip of the endoscope, and the control unit may further control the amount of perfusion fluid supplied from the perfusion pump based on the temperature signal obtained from the temperature sensor.

In another aspect, in any of the above aspects, the control unit may be configured to correct the pressure value indicated by the pressure signal based on the temperature signal, and increase or decrease the supply pressure of the perfusion fluid in the perfusion pump so that the corrected pressure value approaches a predetermined reference value.

This configuration makes it possible to detect the pressure near the tip of the endoscope more accurately during surgery, and to supply a constant flow rate to ensure visibility while keeping the internal pressure in the body cavity low when supplying irrigation fluid.

In another aspect, in any of the above aspects, the body cavity is the ureter, the endoscope is inserted through the ureter to at least the upper urinary tract, the perfusion pump supplies liquid into the upper urinary tract or the renal pelvis through the liquid supply channel, the pressure sensor is inserted at least to the upper urinary tract to detect intrapelvic pressure, and the control unit may be configured to set the supply pressure of the perfusion liquid in the perfusion pump so that the detected intrapelvic pressure approaches a set reference value.

With this configuration, in upper urinary tract endoscopic surgery using a nephroscope, the intrapelvic pressure can be detected during surgery, and the intrapelvic pressure when irrigation fluid is supplied can be brought close to a set reference value. As a result, a constant flow rate can be supplied to ensure visibility while maintaining the intrapelvic pressure when irrigation fluid is supplied at a low intrapelvic pressure that is adaptively set for the patient.

In another aspect, any of the above aspects may further include a ureteral access sheath that is inserted from the patient's ureter into the upper urinary tract and guides the endoscope to the upper urinary tract, and the supplied liquid may be discharged outside the body through the access sheath.

This configuration allows the endoscope to be guided to the upper urinary tract, and the inside of the ureteral access sheath can be used as a fluid delivery path to drain the fluid supplied to the renal pelvis outside the body.

In another aspect, in any of the above aspects, the pressure sensor may be configured to include an optical fiber extending in the longitudinal direction, a half mirror formed from one end of the optical fiber, a peripheral wall surrounding the first mirror in the longitudinal direction, a diaphragm arranged at the end of the peripheral wall in the longitudinal direction, forming an air chamber together with the first mirror and the peripheral wall, and displaced into the air chamber by external pressure, a second mirror arranged on the diaphragm facing the first mirror, a measuring unit that measures the change in phase difference between light entering from the other end of the optical fiber and reflected by the first mirror and light entering from the other end of the optical fiber and reflected by the second mirror, and a pressure calculating unit that calculates the external pressure applied to the diaphragm based on the change in phase difference.

This configuration makes it possible to construct a pressure sensor that can detect the pressure near the tip of an endoscope inserted into a body cavity without sacrificing much of the capacity of the fluid delivery channel.

In addition, a method of operating a perfusion fluid supply system according to an embodiment of the present disclosure is a method of operating a perfusion fluid supply system for an endoscope inserted into a body cavity, which is characterized by detecting pressure near the tip of the endoscope using a pressure sensor extending to the endoscope, controlling the supply pressure of perfusion fluid in a perfusion pump based on the pressure signal obtained from the pressure sensor, supplying fluid to the vicinity of the tip of the endoscope through a fluid delivery channel extending to the vicinity of the tip of the endoscope, and discharging the supplied fluid to the outside of the body through the body cavity.

This configuration makes it possible to detect the pressure near the tip of the endoscope during surgery and supply irrigation fluid so as to bring the internal pressure in the body cavity close to a set reference value. As a result, it is possible to supply a constant flow rate to ensure visibility while keeping the internal pressure in the body cavity at the time of supplying irrigation fluid within a pressure range that is adaptively set for the patient.

In another aspect, in any of the above aspects, the supply pressure may be controlled based on a temperature signal obtained from a temperature sensor that extends through the endoscope and detects the temperature near the tip of the endoscope.

This configuration makes it possible to detect the pressure near the tip of the endoscope more accurately during surgery, and to supply irrigation fluid so as to bring the internal pressure in the body cavity closer to the set reference value.

In another aspect, in any of the above aspects, the liquid may be discharged through an access sheath that guides the endoscope into the body cavity.

This configuration allows the supply and discharge of perfusion fluid while maintaining a low internal pressure within the body cavity when perfusion fluid is being supplied, and allows perfusion fluid to be supplied at a constant flow rate to ensure visibility.

First Embodiment
A perfusion fluid supply system 1 according to the present embodiment will be described with reference to the drawings. Note that the drawings are schematic diagrams and may differ in scale from the actual one. The perfusion fluid supply system 1 (hereinafter referred to as the "perfusion system") is a medical device that allows a doctor or the like to deliver perfusion fluid or gas to a surgical site during endoscopic surgery, and aims to optimize intrapelvic pressure from the viewpoints of ensuring a visual field during surgery and preventing postoperative complications.

<Overall configuration of perfusion system 1>
In upper urinary tract endoscopic surgery, as described above, an endoscope is inserted from the urethra through the bladder and ureter into the upper urinary tract, the tip of the endoscope is inserted into the renal pelvis, and a resection probe or the like is used to treat the target site while observing the surgical site. Alternatively, an access sheath is inserted from the urethra through the bladder and ureter into the upper urinary tract, and the tip of the endoscope is inserted into the renal pelvis through the access sheath. Fig. 1 is a schematic diagram showing the configuration of a perfusion system 1 according to embodiment 1 configured for upper urinary tract endoscopic surgery. In this specification, the upper direction of the paper in the drawings is the "upper" direction, and the lower direction of the paper is the "lower" direction.

As shown in FIG. 1, the perfusion system 1 includes an access sheath 10, an endoscope 20, a pressure sensor 30, a perfusion device 40, and a control unit 50. These components are connected to form a perfusion system in which a fluid delivery channel and a drainage path are formed.

<Configuration of each part of perfusion system 1>
The configuration of each part of the perfusion system 1 will be described below.

(Access sheath 10)
The access sheath 10 is a flexible tube made of a resin material, and has a tube section 11 to be inserted into a body cavity and a handle section 12 for an operator at the rear of the tube. In this example, the access sheath 10 is inserted into the upper urinary tract via the urethra, bladder, and ureter, and an endoscope 20 is inserted inside the tube, and functions as a guide means for allowing the tip of the endoscope 20 to reach the renal pelvis. Fluid supplied into the renal pelvis is discharged outside the body from the open end 12a of the access sheath 10 through the space between the inner wall of the access sheath 10 inserted into the body cavity and the endoscope 20 (denoted as FB in FIG. 1).

The access sheath 10 may be made of a resin material such as polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyamide, polyimide, or polyacetal. The inner diameter of the tube of the access sheath 10 is selected based on the inner diameter of the patient's ureter from a range of, for example, 3.17 mm to 5.33 mm (9.5 Fr to 16 Fr). Alternatively, it may be selected from a range of 3.17 mm to 4 mm (9.5 Fr to 12 Fr). However, it goes without saying that the tube diameter and material are not limited to the above dimensions and materials.

(Endoscope 20)
The endoscope 20 is a medical instrument whose tip is inserted through the access sheath 10 inserted into the ureter up to the vicinity of the renal pelvis, and which performs treatment on the target site using a resection probe or the like while observing the surgical site. The endoscope 20 is a flexible ureteroscope, and for example, a renal ureter fiberscope URF-P6 manufactured by Olympus Corporation may be used.

The endoscope 20 has a long insertion section 20x that is inserted into the body cavity, and an operating section 25 that is located at the rear of the insertion section 20x and serves as a handle for the operator.

The operating section 25 has an operating lever 251 that allows the operator to adjust the degree of curvature of the curved section, a forceps port 252 for inserting the forceps and treatment tool 60, a fluid supply port 253 to which the water supply channel 411 leading from the irrigation device 40 is connected, and an eyepiece 254 for image observation.

The insertion section 20x is composed of a flexible soft tube 20x1, a bending section 20x2 located on the tip side of the flexible tube and bending in two directions, up and down (up and down in FIG. 1), by operating an operating lever 251 described later, and a tip section 20x3 located at the tip. The flexible tube 20x1 is made of a resin material such as fluororesin, the bending section 20x2 is made of a rubber material such as fluororubber, and the tip section 20x3 is made of a resin material.

Through the tube of the insertion section 20x, there are inserted a perfusion fluid delivery channel 21, an image guide 22 for transmitting images, and a light guide 23 for guiding illumination light.

The image guide 22 is composed of an optical fiber bundle for transmitting an image, and transmits light from the subject incident at the tip 221 to the eyepiece 254 of the operation unit 25.

The light guide 23 is composed of an optical fiber bundle for transmitting illumination light, and receives light output from the light source 23 near the operation unit 25 and emits it from the tip 231.

The fluid delivery channel 21 is made of a resin pipe for delivering perfusion fluid, and delivers the perfusion fluid supplied from the perfusion device 40 via the water supply channel 411 and the fluid delivery port 253 of the operation unit 25 to the tip 20x3 (indicated as FF in Figure 1), and supplies it into the body cavity from the fluid delivery opening 21a located at the tip 20x3.

The fluid supply channel 21 also functions as a surgical tool channel through which forceps and treatment tools are inserted. The forceps and treatment tool 60 are inserted from the forceps port 252 provided in the operation section 25, and the treatment tool tip 61 is extended from the fluid supply opening 21a located at the tip 20x of the insertion section 20x to perform treatment on the target area. A laser scalpel, basket, etc. may be used as the treatment tool. A sealing plug is provided at the forceps port 252 to prevent the irrigation fluid from leaking.

Figure 2 is an exploded perspective view of the vicinity of the tip portion 20x3 of the endoscope 20. The tip portion 20x3 is composed of a tip portion body 202 arranged on the tip side of the bending rubber tube 201 of the bending portion 20x2, and a tip portion cover 203 that covers the tip portion body 202.

The tip body 202 has holes into which the tip 221 of the image guide 22, the tip 231 of the light guide 23, and the tube end 211 of the liquid delivery channel 21 are inserted.

The tip cover 203 has an objective lens 222 arranged at a position corresponding to the tip 221 of the image guide 22, an illumination light emission opening 23a is opened at the position where the tip 231 of the light guide 23 is inserted, and a liquid delivery opening 21a is opened corresponding to the tube end 211 of the liquid delivery channel 21.

(Pressure sensor 30)
The pressure sensor 30 extends inside the endoscope 20 and detects the pressure near the tip of the endoscope 20. To prevent damage, the pressure sensor 30 is installed covered with an outer tube made of a resin material such as polyimide. The pressure sensor 30 is disposed inside the endoscope 20 because the structure is simplified, the perfusion fluid supply system 1 can be easily constructed, and the pressure sensor 30 is disposed in a suitable position for measuring the pressure of the perfusion fluid because the pressure sensor 30 directly contacts the perfusion fluid supplied from the fluid supply channel 21. Specifically, the pressure sensor 30 may be, for example, an optical fiber pressure sensor described in the Journal of the Institute of Electrical Engineers, Vol. 136, No. 3, 2016 (pp. 147-150) or a patent publication (JP Patent No. 3393370).

The pressure sensor 30 has an optical fiber 31 extending within the liquid delivery channel 21, a pressure detection unit 32 located at the tip of the optical fiber 31, a measurement unit 33 to which the optical fiber 31 is connected, which is led out from the liquid delivery port 253 of the operation unit 25 of the endoscope 20, and a pressure calculation unit 34.

Figure 3(a) is a schematic diagram showing an outline of the configuration of the pressure sensor 30. As shown in Figure 3(a), the pressure sensor 30 is configured with one end of an optical fiber 31 connected to a measuring unit 33 and the other end equipped with a pressure detection unit 32.

The measurement unit 33 has a white light source 331, a spectroscope 332, a photocoupler 33, and an optical fiber 31 connecting them. The light emitted by the white light source 331, which is bottom coherence light, is transmitted to the pressure detection unit 32 by the optical fiber 31 via the photocoupler 33. The pressure detection unit 32 is configured as a Fabry-Perot interferometer, and the interference light generated between the diaphragm and the half mirror at the end face of the optical fiber is transmitted to the photocoupler 33 by the optical fiber 31, and reaches the spectroscope 332 via the photocoupler 33 and is detected.

The pressure calculation unit 34 calculates the displacement exerted on the diaphragm 323 based on the wavelength change of the interference spectrum, and calculates the external pressure from the amount of displacement relative to the pressure measured in advance.

Figure 3(b) is an enlarged view of part A (pressure detection unit 32) in Figure 3(a). As shown in Figure 3(b), the pressure detection unit 32 has a first mirror 321 composed of one end of an optical fiber 31 extending in the longitudinal direction, a peripheral wall 322 surrounding the first mirror 321 in the longitudinal direction, a diaphragm 323 arranged at the end of the longitudinal direction of the peripheral wall 322, which constitutes an air chamber 325 together with the first mirror 321 and the peripheral wall 322 and is displaced in and out of the air chamber 325 by external pressure, and a second mirror 324 arranged on the diaphragm 323 facing the first mirror 321. The second mirror 324 has a higher reflectivity than the first mirror 321, and the second mirror 324 may be a total reflection mirror and the first mirror 321 may be a half mirror.

Specifically, the optical fiber 31 has a diameter (d1) of, for example, 125 μm, and a dielectric half-mirror layer made of zinc sulfide (ZnS) or a half-mirror layer made of chromium (Cr) is formed on one end of the optical fiber 31 to form the first mirror 321. The first mirror 321 may be formed by a vapor phase growth method such as a vacuum deposition method or a sputtering method.

The peripheral wall 322 has a length l in the major axis direction of approximately 2 to 6 μm, and a thickness t1 in the direction perpendicular to the major axis direction of approximately 15 μm.

The diaphragm 323 has a diameter (d2) of about 120 μm and a thickness (t2) of about 0.7 μm, is made of a silicon oxide film, and may be formed by a vapor phase growth method such as a CVD method. The diaphragm 323 has a diameter (d3) of about 60 μm and a thickness (t3) of 2.3 μm centered on the center in the long axis direction, and a protrusion 323a (protrusion step is 1.6 μm) that protrudes from the first mirror 321, and the second mirror 324 is placed on the top surface of the protrusion 323a.

The second mirror 324 has a diameter (d3) of approximately 50 μm and a thickness (t4) of approximately 0.1 μm, and is made of a metal, for example, aluminum (AL), and may be formed by a vapor deposition method such as vacuum deposition or sputtering.

With the above configuration, in the pressure detection unit 32, when the diaphragm 323 is not deformed by external pressure, the first mirror 321 and the second mirror 324 face each other in the long axis direction, separated by a distance of approximately 2.5 μm.

It goes without saying that the above materials, shapes, dimensions, etc., of the components of the pressure sensor 30 are merely examples and are not limited to those described above.

Figures 4(a) and (b) are schematic diagrams for explaining the principle of pressure measurement in the pressure sensor 30.

Light emitted by the white light source 331 of the measuring unit 33 is transmitted to the pressure detection unit 32 by the optical fiber 31 via the photocoupler 33. Then, interference fringes corresponding to the gap length between the optical fiber and the diaphragm are generated in the pressure detection unit 32, and the interference light (R1, R2) transmitted through the half mirror is transmitted to the photocoupler 33 by the optical fiber 31, reaches the spectroscope 332 via the photocoupler 33, and is detected as an interference spectrum. At this time, the change in the diaphragm is measured from the peak wavelength of the interference spectrum. For this measurement, for example, the method described in K. Totsu, Y. Haga and M. Esashi, "Ultra-miniature fiber-optic pressure sensor using white light interferometry", J. Micromech. Microeng. 15 (2005), pp. 71-75., V. Bhatia, M. B. Sen, K. A. Murphy and R. O. Claus, "Wavelength-tracked white light interferometry for highly sensitive strain and temperature measurements", Electron. Lett., Vol.32, No.3, pp.247-249, (1996) can be used.

The pressure applied to the diaphragm 323 is calculated based on the relationship between the pressure applied to the diaphragm 323 and the amount of change in the spectral peak wavelength, which has been determined in advance through experiments, etc.

This makes it possible to construct a pressure sensor that can detect the pressure near the tip of the endoscope 20 inserted into a body cavity, without sacrificing much of the capacity of the fluid supply channel 21. Specifically, in upper urinary tract endoscopic surgery, when the access sheath 10 is inserted into the patient's upper urinary tract, the endoscope 20 is inserted through the access sheath 10 at least up to the upper urinary tract, and fluid is supplied into the upper urinary tract or renal pelvis through the fluid supply channel 21, the pressure sensor 30 is inserted at least up to the upper urinary tract and can detect intrapelvic pressure.

(Perfusion Device 40)
The perfusion device 40 is a continuous perfusion device that is connected to the fluid supply port 253 of the endoscope 20 via a water supply channel 411 and supplies perfusion fluid to the vicinity of the tip 20x of the endoscope through the fluid supply channel 21. The supplied perfusion fluid is discharged to the outside of the body from the open end 12a of the access sheath 10 through the space between the inner wall of the access sheath 10 and the endoscope 20 due to the supply pressure of the perfusion fluid from the perfusion device 40. The perfusion device 40 includes a perfusion pump 41 for supplying water that is connected to the water supply channel 411. The perfusion pump 41 controls the discharge pressure of the perfusion fluid (apparatus outlet pressure) to increase or decrease based on a control signal output from the control unit 50.

The perfusion pump 41 may be, for example, a constant rate fluid delivery pump RP-1100 manufactured by Tokyo Rikakikai Co., Ltd. In this device, by inputting an input voltage of 0 to 5 V as a control signal to an external signal input terminal, the discharge pressure of the perfusion fluid can be controlled within a range of 0 to 1.4 kg/ ^cm2 according to the input voltage value, thereby controlling the flow rate of the perfusion fluid. The perfusion pump 41 may be configured to be shared by the same pump.

As a result, in upper urinary tract endoscopic surgery, while the access sheath 10 is inserted into the patient's upper urinary tract through the ureter, the endoscope 20 is inserted through the access sheath 10 at least up to the upper urinary tract, and the perfusion pump 41 continuously supplies liquid into the upper urinary tract or renal pelvis through the liquid delivery channel 21, and the supplied liquid can be discharged outside the body through the space within the access sheath 10.

(Control unit 50)
The control unit 50 is electrically connected to the pressure sensor 30 and the perfusion pump 41 , and controls the amount of perfusion fluid supplied from the perfusion pump 41 based on the output signal from the pressure sensor 30 .

Specifically, the control unit 50 receives an electrical signal indicating the pressure applied to the diaphragm 323 from the pressure calculation unit 34, and performs feedback control by increasing or decreasing the supply pressure of the perfusion fluid in the perfusion pump 41 so that the detected pressure value approaches a set reference value, and further repeating pressure detection by the pressure sensor 30. At this time, for example, the control unit 50 may vary the amount by which the supply pressure of the perfusion fluid in the perfusion pump 41 is gradually increased or decreased based on the difference between the detected pressure value and the reference value.

<Evaluation test>
The performance of the perfusion fluid supply system 1 according to the embodiment was evaluated through a preliminary test and an evaluation test. The results are described below.

(Preliminary test)
The inventors have used the perfusion fluid supply system 1 and a number of different commercially available access sheaths to perform a preliminary evaluation of the relationship between the discharge pressure of the perfusion pump and the intrapelvic pressure or the perfusion fluid flow rate. The test conditions are as follows:

[Test conditions and methods]
Using the perfusion fluid supply system 1, an access sheath was inserted from the upper urinary tract of a pig into the renal pelvis, and with the tip of the endoscope inserted into the renal pelvis, the supply pressure (discharge pressure) of the perfusion pump was changed from 40 mbar to 180 mbar to intermittently deliver the perfusion fluid, and the intrapelvic pressure and the perfusion fluid flow rate were measured. Here, the intrapelvic pressure was measured by inserting a nephrostomy catheter into the renal pelvis, and the pressure in the renal pelvis was measured with an arterial pressure measuring device. The perfusion fluid flow rate was measured with the perfusion pump.

Five types of commercially available access sheaths were used as test samples (Sample A: Cook Medical "Flexor" (registered trademark) 9.5/11.5 Fr, Sample B: Olympus "UroPass" (registered trademark) 10/12 Fr, Sample C: Rocamed "BI-FLEX" (registered trademark) 10/12 Fr, Sample D: BARD "PROXIS" (registered trademark) 10/12 Fr, Sample E: Coloplast "ReTrace" (registered trademark) 10/12 Fr). The endoscope 20 used was a URF-P6 pelvic and ureteral fiberscope manufactured by Olympus Corporation. Figure 5 (a) shows the access sheath used in the test sample, and (b) shows the configuration of the endoscope.

[Test results]
Fig. 6 shows the experimental results showing the relationship between the supply pressure of the perfusion fluid and the renal pelvic pressure. As shown in Fig. 6, in samples D and E, in which the cross-sectional area of the access sheath duct is ^8-9 mm2, the intrapelvic pressure is equal to or higher than the reference intrapelvic pressure of ₄₀ cmH2O when the supply pressure of the perfusion pump is 140 mbar or higher, and in sample A, in which the cross-sectional area is 7-8 ^mm2 , the intrapelvic pressure is equal to or higher than the reference intrapelvic pressure of ₄₀ cmH2O when the supply pressure of the perfusion pump is 80 mbar or higher. In contrast, in samples B and C, in which the cross-sectional area is larger than ⁹ mm2, the intrapelvic pressure is lower than the reference intrapelvic pressure of ₄₀ cmH2O over the entire range of the supply pressure of the perfusion pump from 40 mbar to 180 mbar.

Fig. 7 shows the experimental results showing the relationship between the supply pressure of the perfusion fluid and the supply amount of the perfusion fluid. As shown in Fig. 7, in the entire range of the supply pressure of the perfusion pump from 40 mbar to 180 mbar, the supply amount of the perfusion fluid increases with an increase in the cross-sectional area, and the samples B and C with a cross-sectional area larger than 9 ^mm2 had the largest supply amount.

Based on the above results, it is preferable to use sample B or C as the access sheath 10 from the standpoint of intrapelvic pressure and perfusion fluid flow rate.

(Evaluation test using perfusion fluid supply system 1)
The inventors have measured the relationship between the intrapelvic pressure measured using a nephrostomy catheter and the intrapelvic pressure detected by a pressure sensor, using the perfusion fluid supply system 1. The test conditions are as follows.

[Test Condition 1, Method]
Using the perfusion fluid supply system 1, an access sheath was inserted into the renal pelvis from the upper urinary tract of a pig, and with the tip of the endoscope inserted into the renal pelvis, the supply pressure (discharge pressure) of the perfusion pump was changed in ascending order to 60, 80, 100, 120, 140, 160, and 180 mbar to intermittently deliver perfusion fluid at a temperature of 37.0°C, and the intrapelvic pressure and the perfusion fluid flow rate were measured. Here, the intrapelvic pressure was measured by the pressure sensor 30 in the perfusion fluid supply system 1 (solid line in Figure 8). In addition, in order to verify the measurement results of the intrapelvic pressure, a catheter for nephrostomy (A-line pressure) was inserted into the renal pelvis, and the intrapelvic pressure was measured by an arterial pressure measuring device (dashed line in Figure 8). The perfusion fluid flow rate was measured by the perfusion pump. The access sheath B or C shown in Figure 5(a) was used, and the endoscope shown in Figure 5(b) was used.

[Test result 1]
8 shows experimental results showing the change over time in the renal pelvic pressure accompanying the supply of perfusion fluid in the perfusion fluid supply system 1. Specifically, the experimental results show the change over time in the renal pelvic pressure measured using a nephrostomy catheter and the renal pelvic pressure detected by a pressure sensor during the supply of perfusion fluid in the perfusion fluid supply system 1.

As shown in Figure 8, when pressurized to 60 and 80 mbar, the pressure measured by the pressure sensor was lower than the A-line pressure. This is presumably due to the influence of flow path resistance.

In addition, when pressurized to 100, 120, and 140 mbar, the pressure measured by the pressure sensor matched the A-line pressure.

In addition, when pressurized to 160 and 180 mbar, the pressure measured by the pressure sensor and the A-line pressure were almost the same immediately after pressurization, but the pressure measured by the pressure sensor decreased during the pressurization period, and the difference with the A-line pressure gradually increased. The pressure measured by the pressure sensor became 0 or less after pressurization.

The changes in intrapelvic temperature during each pressurization period from 60 to 180 mbar are shown below.

When pressurized to 160 and 180 mbar, the increase in intrapelvic temperature is greater than when pressurized to 100, 120, and 140 mbar. The temperature of the perfusate is higher than body temperature, and when the supply pressure is high, as shown in Figure 7, the amount of perfusate supplied is large, so it is thought that the increase in intrapelvic temperature is greater when pressurized to 160 and 180 mbar. The gradual increase in the difference between the pressure measured by the pressure sensor and the A-line pressure during the pressurization periods of 160 and 180 mbar shows the same trend as the increase in intrapelvic temperature, so it is presumed to be due to the increase in intrapelvic temperature during the pressurization period.

The above results confirmed that when using the perfusion fluid supply system 1, the pressure sensor can properly detect intrapelvic pressure when pressurized to 100, 120, and 140 mbar.

When pressurizing to 160 or 180 mbar, the intrapelvic pressure can be detected by the pressure sensor immediately after pressurization, but it has been confirmed that the pressure measured by the pressure sensor gradually decreases during the pressurization period in response to the increase in intrapelvic temperature during the pressurization period. Therefore, in order to minimize the effect of the pressure sensor on the change in intrapelvic temperature, a perfusion fluid supply system 1B according to embodiment 2 that enables temperature correction will be described later.

[Test Condition 2, Method]
Using the perfusion fluid supply system 1, an access sheath was inserted into the renal pelvis from the upper urinary tract of a pig, and the tip of the endoscope was inserted into the renal pelvis, and an evaluation experiment was conducted on the feedback control of the intrapelvic pressure based on the measurement value of the pressure sensor 30 during the supply of perfusion fluid by the perfusion fluid supply system 1. Specifically, the target values of the intrapelvic pressure of 5, 10, 15, and 20 mmHg were set in the control unit 50 in ascending and descending order, and the supply pressure (discharge pressure) of the perfusion pump 41 was controlled to increase or decrease so that the output of the measurement value of the intrapelvic pressure from the pressure sensor 30 approached the target value, thereby feeding the perfusion fluid into the renal pelvis. In this state, the intrapelvic pressure was measured by the pressure sensor 30 and an arterial pressure measuring device as a reference. The temperature of the access sheath, the endoscope, and the perfusion fluid, as well as the other feeding conditions, were the same as those in the test condition 1.

[Test result 2]
9 shows the measurement results of the intrapelvic pressure during feedback control of the intrapelvic pressure using the pressure sensor 30 in the supply of perfusion fluid by the perfusion fluid supply system 1, where (a) is the result when the pressure is increased and (b) is the result when the pressure is decreased. Fig. 9 shows the intrapelvic pressure detected by the pressure sensor 30 (solid line (thick): indicated as "Optic pressure sensor"), the intrapelvic pressure measured by an arterial pressure measuring device using a nephrostomy catheter (dashed line (thin): indicated as "Reference pressure sensor"), and the measured value shows the change over time of the rotation speed of the perfusion pump 41 (solid line (middle): indicated as "Irrigation pump").

From Figures 9(a) and (b), it was confirmed that the intrapelvic pressure detected by the pressure sensor 30 throughout the entire measurement period during both the increase and decrease of blood pressure was consistent with the intrapelvic pressure measured by the arterial pressure measuring device.

As shown in Figures 9(a) and (b), when the set value is increased to 5, 10, 15, and 20 mmHg, the rotation speed of the perfusion pump 41 increases accordingly, and it was confirmed that both the intrapelvic pressure measured by the pressure sensor 30 and the intrapelvic pressure measured by the arterial pressure measuring device generally reach the target pressure. It was also confirmed that the pressure is similarly decreased in accordance with the target pressure when decreasing. It was also confirmed that at 15 mmHg or more, it takes about one minute for the intrapelvic pressure to reach the set pressure when increasing or decreasing the pressure.

The above results confirmed that, when the tip of the endoscope is inserted into the renal pelvis from the upper urinary tract using the perfusion fluid supply system 1, feedback control of the intrapelvic pressure during perfusion fluid supply is possible using the measurement value of the pressure sensor 30 of the perfusion fluid supply system 1.

<Effects of perfusion system 1>
It has been confirmed that in the perfusion fluid supply system 1, the pressure sensor 30 can appropriately detect the intrapelvic pressure within the above-mentioned pressure range.

In the perfusion fluid supply system 1, the control unit 50 uses the pressure sensor 30 to perform feedback control of the perfusion fluid supply pressure in the perfusion pump 41 so that the pressure value detected by the pressure sensor 30 approaches a set reference value, thereby controlling the pressure near the tip of the endoscope 20 where the pressure sensor 30 is located to approach the reference value.

As a result, with the perfusion fluid supply system 1, in an upper urinary tract endoscopic surgery, the access sheath 10 is inserted into the patient's upper urinary tract, the endoscope 20 is inserted through the access sheath 10 up to at least the upper urinary tract, and fluid is supplied into the upper urinary tract or the renal pelvis through the fluid supply channel 21. In this state, the pressure sensor 30 is inserted at least up to the upper urinary tract to detect the intrapelvic pressure, and the control unit 50 sets the supply pressure of the perfusion fluid in the perfusion pump 41 so that the detected intrapelvic pressure approaches a set reference value, and the perfusion pump 41 can supply fluid into the upper urinary tract or the renal pelvis through the fluid supply channel 21 at the set supply pressure.

<Summary>
As described above, the perfusion fluid supply system 1 of embodiment 1 is characterized by comprising an endoscope 20 to be inserted into a body cavity, a fluid supply channel 21 extending within the endoscope 20 to near the tip of the endoscope 20, a pressure sensor 30 extending within the endoscope 20 and detecting the pressure near the tip of the endoscope 20, a perfusion pump 40 that supplies fluid to the vicinity of the tip of the endoscope 20 through the fluid supply channel 21 and discharges the supplied fluid to the outside of the body via the body cavity, and a control unit 50 that controls the supply pressure of the perfusion fluid in the perfusion pump 40 based on a pressure signal, which is an electrical signal indicating the pressure obtained from the pressure sensor 30.

With this configuration, the perfusion fluid supply system 1 can detect the intrapelvic pressure during upper urinary tract endoscopic surgery and bring the intrapelvic pressure when perfusion fluid is supplied close to a set reference value. As a result, it is possible to supply a constant flow rate to ensure visibility while maintaining the intrapelvic pressure when perfusion fluid is supplied at a low intrapelvic pressure that is adaptively set for the patient.

<Modification 1>
Although one embodiment has been described above as an example, for example, embodiments obtained by applying various modifications to the first embodiment are also included in the present disclosure.

Below, we will explain variant 1 as an example of such a configuration.

In the perfusion fluid supply system 1 according to the first embodiment, the access sheath 10 is inserted into the upper urinary tract via the urethra, the bladder, and the ureter, and the tip of the endoscope is inserted into the renal pelvis through the access sheath 10. In the perfusion fluid supply system 1, the fluid supplied into the renal pelvis is discharged to the outside of the body from the open end 12a of the access sheath 10 through the space between the inner wall of the access sheath 10 inserted into the body cavity and the endoscope 20. However, the perfusion fluid supply system according to the present disclosure may be configured to control the pressure when the perfusion fluid is supplied into the living body through the fluid supply channel extending to the vicinity of the tip of the endoscope inserted into the body cavity, and the guide means for inserting the endoscope into the body cavity and the drainage path from the living body may be appropriately changed.

Figure 10 is a schematic diagram showing the configuration of a perfusion fluid supply system 1A according to the first modification. As shown in Figure 10, in the perfusion fluid supply system 1A according to the first modification, the endoscope 10 is inserted directly into the body cavity without using an access sheath as a guide means. The fluid supplied into the living body is discharged to the outside of the body through the space between the inner wall of the body cavity and the endoscope 10. That is, it differs from the perfusion fluid supply system 1 according to the first embodiment in that it does not use the access sheath 10, but otherwise has the same configuration as the perfusion fluid supply system 1. In Figure 10, the same components as those in the perfusion system 1 are given the same numbers and will not be described.

In the perfusion fluid supply system 1A, the endoscope 10 is directly inserted into the body cavity, which reduces the possibility of the ureter being damaged by the access sheath when the patient's ureter has a small diameter. In this configuration, the perfusion fluid supplied into the living body is discharged outside the body through a hole on the body surface of the ureter through a gap between the inner wall of the ureter, which is a body cavity, and the endoscope 20 due to the supply pressure of the perfusion fluid from the perfusion device 40, as shown in FIG. 10 (denoted as FB in FIG. 10).

With this configuration, the perfusion fluid supply system 1A reduces the possibility of ureteral damage, and, similar to the first embodiment, in upper urinary tract endoscopic surgery, it is possible to detect the intrapelvic pressure during surgery and bring the intrapelvic pressure when perfusion fluid is supplied closer to a set reference value. As a result, it is possible to supply a constant flow rate to ensure visibility while maintaining the intrapelvic pressure when perfusion fluid is supplied at a low intrapelvic pressure that is adaptively set for the patient.

Second Embodiment
The perfusion system 1 of embodiment 1 has a pressure sensor 30 extending inside the endoscope 20 and detecting the pressure near the tip of the endoscope 20, and the control unit 50 is configured to control the supply pressure of the perfusion fluid in the perfusion pump 41 based on the output signal from the pressure sensor 30.

The perfusion system 1B according to the second embodiment differs from the first embodiment in that it further includes a temperature sensor 70A that extends into the endoscope 20 and detects the temperature near the tip of the endoscope 20, and the control unit 50A is configured to control the supply pressure of the perfusion fluid in the perfusion pump 40 based on the output signals from the pressure sensor 30 and the temperature sensor 70A.

The following describes the perfusion system 1B according to the second embodiment with reference to the drawings.

<Configuration of perfusion system 1B>
Fig. 11 is a schematic diagram showing the configuration of an irrigation fluid supply system 1B according to embodiment 2. Fig. 12 is an exploded perspective view of the vicinity of the tip of an endoscope 20 in the irrigation fluid supply system 1B.

Perfusion system 1B differs from perfusion system 1 according to embodiment 1 in that it includes a temperature sensor 70A and a control unit 50A, but otherwise has the same configuration as perfusion system 1 shown in FIG. 1.

Below, we will explain the configuration of the temperature sensor 70A and control unit 50A of the perfusion system 1B, and other components will be given the same numbers as those of the perfusion system 1 and will not be explained.

(Temperature sensor 70A)
The temperature sensor 70A is a temperature sensor that extends inside the endoscope 20 and detects the temperature in the vicinity of the tip of the endoscope 20. Specifically, for example, a temperature sensor catheter can be used.

The temperature sensor 70A has a lead wire 71A extending inside the endoscope 20, a temperature detection unit 711A located at the tip of the lead wire 71A, and a temperature measurement unit 72A to which the lead wire 71A is connected, the lead wire 71A being led out from the liquid delivery port 253 of the operation unit 25 of the endoscope 20.

The temperature detection unit 711A is composed of a temperature detection element such as a thermistor.

The temperature measurement unit 72A calculates the amount of change in temperature from, for example, the change in resistance value detected by the temperature detection unit 711A, and calculates the temperature around the temperature detection unit 711A, which has been determined in advance through experiments, etc.

As a result, when the access sheath 10 is inserted into the patient's upper urinary tract, the endoscope 20 is inserted through the access sheath 10 at least up to the upper urinary tract, and liquid is being supplied into the upper urinary tract or renal pelvis through the liquid supply channel 21, the temperature sensor 70A is inserted at least up to the upper urinary tract and can detect the temperature inside the upper urinary tract (ureter, renal pelvis).

Figure 12 is an exploded perspective view of the vicinity of the tip portion 20x3 of the endoscope 20 in the irrigation fluid supply system 1B. As in the first embodiment, the tip portion 20x3 is composed of a tip portion body 202 and a tip portion cover 203 that covers the tip portion body 202.

The tip body 202 has holes into which the tip 221 of the image guide 22, the tip 231 of the light guide 23, the tube end 211 of the liquid delivery channel 21, and the temperature detection part 711A of the temperature sensor 70 are inserted.

In addition to the objective lens 222, the illumination light exit opening 23a, and the liquid delivery opening 21a, the tip cover 203 also has an opening 71a corresponding to the temperature detection part 711A of the temperature sensor.

(Control unit 50A)
The control unit 50A is electrically connected to the pressure sensor 30, the temperature sensor 70A and the perfusion pump 41, and controls the amount of perfusion fluid supplied from the perfusion pump 41 based on output signals from the pressure sensor 30 and the temperature sensor 70A.

Specifically, the control unit 50 receives an electrical signal indicating the pressure applied to the diaphragm 323 from the pressure calculation unit 34, as well as an electrical signal indicating the temperature around the temperature detection unit 711A output by the temperature measurement unit 72A. The control unit 50 then corrects the detected pressure value based on the detected temperature information, and controls the supply pressure of the perfusion fluid by increasing or decreasing the supply pressure of the perfusion fluid in the perfusion pump 41 so that the corrected pressure value approaches the set reference value.

<Effects of perfusion system 1B>
In upper urinary tract endoscopic surgery, the following factors may cause temperature rise within the renal pelvis, including the upper urinary tract:

First, as shown in Figure 8, when the temperature of the perfusion fluid is higher than body temperature and the supply pressure is high, it is thought that the temperature in the renal pelvis will rise.

In addition, according to the inventor's experiments, it has been confirmed that in upper urinary tract endoscopic surgery, the temperature inside the renal pelvis also rises when treating the target area with a laser scalpel.

Figures 13 and 14 show the measurement results showing the time change in temperature associated with laser irradiation during upper urinary tract endoscopic surgery. The same configuration as the perfusion system 1 was used for the perfusion fluid supply system. Figure 13 shows the measurement results for the temperature change in the renal pelvis when a 12/14 Fr access sheath was used, and Figure 14 shows the measurement results when a 10/12 Fr access sheath was used, with different applied energy, frequency, and pulse width of the laser light.

As shown in Figures 13 and 14, it can be seen that the temperature inside the renal pelvis increases with laser irradiation. In Figure 14, where a 10/12 Fr access sheath was used, the capacity of the drainage channel is smaller and the cooling effect of the irrigation fluid is smaller than in Figure 13, where a 12/14 Fr access sheath was used, so it is presumed that the temperature rise with laser irradiation is greater.

When such a temperature rise occurs in the renal pelvis, it is believed that the pressure detected by the pressure sensor will gradually decrease in response to the temperature rise in the renal pelvis, as shown in Figure 8.

In response to the decrease in pressure detection accuracy that accompanies this temperature rise, the perfusion fluid supply system 1B has an access sheath 10 inserted into the patient's upper urinary tract, an endoscope 20 inserted through the access sheath 10 up to at least the upper urinary tract, and fluid being supplied into the upper urinary tract or the renal pelvis through the fluid supply channel 21. In this state, the pressure sensor 30 is inserted at least up to the upper urinary tract to detect the intrapelvic pressure, and the temperature sensor 70A is inserted at least up to the upper urinary tract to detect the temperature inside the renal pelvis. The control unit 50A then corrects the detected intrapelvic pressure value based on the detected temperature information, and sets the supply temperature of the perfusion fluid in the perfusion pump 41 so that the corrected pressure value approaches the set reference value, allowing the perfusion pump 41 to supply fluid into the upper urinary tract or the renal pelvis through the fluid supply channel 21 at the set supply temperature.

<Summary>
As described above, the perfusion fluid supplying system 1B according to the second embodiment is characterized in that, in addition to the perfusion fluid supplying system 1 according to the first embodiment, it further comprises a temperature sensor 70A extending into the endoscope 20 and detecting the temperature near the tip of the endoscope 20, and the control unit 50A further controls the supply pressure of the perfusion fluid in the perfusion pump 40 based on a temperature signal, which is an electrical signal indicating the temperature obtained from the pressure sensor 30 and the temperature sensor 70A. The control unit 50A may also be configured to correct the pressure value indicated by the pressure signal based on the temperature signal, and to increase or decrease the supply pressure of the perfusion fluid in the perfusion pump 40 so that the corrected pressure value approaches a predetermined reference value.

With this configuration, the perfusion fluid supply system 1B can detect the intrapelvic pressure more accurately during upper urinary tract endoscopic surgery, and can supply a constant flow rate to ensure visibility while maintaining a low intrapelvic pressure when supplying perfusion fluid.

Other Modifications
Although the specific configuration of the present disclosure has been described above using the embodiments as examples, the present disclosure is not limited to the above embodiments except for its essential characteristic components. For example, the present disclosure also includes forms obtained by applying various modifications to the embodiments and forms realized by arbitrarily combining the components and functions of each embodiment within the scope of the present invention.

Below, a modified example will be described as an example of such a form.
(1) In the above embodiment, the perfusion fluid supply system 1, 1A, 1B is configured such that the fluid supply channel 21 extending into the endoscope 20 functions as a surgical tool channel through which the forceps and treatment tools are inserted. However, the surgical tool channel may be configured to be a channel independent of the fluid supply channel 21, and the surgical tool channel may be configured to be arranged outside the fluid supply channel 21. This makes it possible to prevent the capacity of the fluid supply channel from decreasing when the forceps and treatment tools are inserted into the endoscope 20 during surgery, thereby preventing a decrease in the flow rate. (2) In the above embodiment, the perfusion fluid supply system 1, 1A, 1B is configured such that the pressure sensor 30 is extended into the fluid supply channel 21 in the endoscope 20. This is because the structure for arranging the pressure sensor 30 is simple and is suitable for measuring the pressure of the perfusion fluid. However, the pressure sensor 30 may be arranged outside the fluid supply channel 21. This makes it possible to increase the capacity of the fluid supply channel.

Also, the pressure sensor 30 may be built inside the endoscope 20, and a line may be constructed in which the fiber 31 for transmitting the signal from the pressure sensor 30 and the image guide 22 for transmitting the image of the endoscope 20 are integrated. Furthermore, a dedicated device in which the control parts of the image system of the endoscope and the irrigation fluid supply system are linked or integrated may be constructed and connected to this integrated line output.
(3) In the perfusion fluid supply system 1B according to the above embodiment, the temperature sensor 70A is disposed within the endoscope 20 so as to extend outside the fluid supply channel 21. However , the temperature sensor 70A may also be disposed so as to extend within the fluid supply channel 21. This simplifies the structure and makes it easier to construct the perfusion fluid supply system 1B.
(4) In the above-described embodiment, the perfusion fluid supplying system 1, 1B is configured to drain the perfusion fluid supplied into the renal pelvis through the space between the inner wall of the access sheath 10 and the endoscope 20, which serves as a drainage path . However , the drainage channel may be disposed independently extending within the endoscope 20.
(5) In the above embodiment, the irrigation fluid supply systems 1, 1A, and 1B are described taking an upper urinary tract endoscopic surgery using a nephroscope as an example in the treatment of urological diseases. However, the use of the irrigation fluid supply system and the operation method of the irrigation fluid supply system according to the present invention is not limited to upper urinary tract endoscopic surgery, and can be widely used in endoscopic surgery performed by supplying irrigation fluid.

<Additional Information>
The above-described embodiments each show a preferred specific example of the present invention. The numerical values, shapes, materials, components, the arrangement and connection of the components, steps, and the order of steps shown in the embodiments are merely examples and are not intended to limit the present invention. Furthermore, among the components in the embodiments, those not described in the independent claims showing the highest concept of the present invention are described as optional components constituting a more preferred embodiment.

The order in which the above methods are performed is merely an example to specifically explain the present invention, and orders other than those described above may also be used. Furthermore, some of the above methods may be performed simultaneously (in parallel) with other methods.

In order to facilitate understanding of the invention, the scale of the components in the figures shown in the above embodiments may differ from the actual scale. Furthermore, the present invention is not limited to the description of the above embodiments, and may be modified as appropriate without departing from the gist of the present invention.

Furthermore, at least some of the functions of each embodiment and its modified examples may be combined.

The perfusion fluid supply system and the method of operating the perfusion fluid supply system according to one aspect of the present disclosure can be widely used in medical care as a medical support means for delivering perfusion fluid or gas to a surgical site during endoscopic surgery.

LIST OF SYMBOLS 1, 1A Irrigation fluid supply system 10 Access sheath 11 Tube section 11a Fluid supply path 12 Handle section 12a Open end 20 Endoscope 20x Insertion section 20x1 Flexible tube 20x2 Bending section 201 Bending rubber tube 20x3 Tip section 202 Tip section body 203 Tip section cover 21 Fluid supply channel 22 Image guide 221 Tip section 222 Objective lens 23 Light guide 231 Tip section 232 Light source 25 Operation section 251 Operation lever 252 Forceps port 253 Fluid supply port 254 Eyepiece section 30 Pressure sensor 31 Optical fiber 32 Pressure detection section 321 First mirror 322 Spacer 323 Diaphragm 322a Protrusion 324 Second mirror 325 Air chamber 33 Measuring unit 34 Pressure calculation unit 40 Perfusion device 41 Perfusion pump 411 Water supply line 50, 50A Control unit 60, 61 Treatment tool 70A Temperature sensor

Claims (8)

A perfusion fluid supply system for use in endoscopic surgery, comprising:
An endoscope that is inserted into a body cavity;
a liquid supply channel extending within the endoscope to a vicinity of a tip of the endoscope;
a pressure sensor extending within the endoscope for detecting a pressure near a tip of the endoscope;
a temperature sensor extending into the endoscope for detecting a temperature in the vicinity of a tip of the endoscope;
a perfusion pump connected to the liquid supply channel, supplying liquid to the vicinity of the tip of the endoscope through the liquid supply channel and discharging the supplied liquid to the outside of the body through a body cavity;
a control unit that controls a supply pressure of the perfusion fluid in the perfusion pump based on a pressure signal acquired from the pressure sensor and a temperature signal acquired from the temperature sensor,
The control unit corrects the time change in the pressure value indicated by the pressure signal during the pressurization period, which gradually decreases as the amount of liquid supplied near the tip of the endoscope increases, based on the temperature signal, and controls the amount of perfusion liquid supplied from the perfusion pump by increasing or decreasing the supply pressure of the perfusion liquid in the perfusion pump so that the corrected pressure value approaches a predetermined reference value. The irrigation fluid supply system according to claim 1 , wherein the control unit corrects a change in the pressure value indicated by the pressure signal, which is caused by a temperature rise in a target site near the tip of the endoscope, based on the temperature signal. The body cavity is the ureter,
The endoscope is inserted through the ureter to at least the upper urinary tract;
The perfusion pump supplies fluid into the upper urinary tract or the renal pelvis through the fluid supply channel;
The pressure sensor is inserted at least to the upper urinary tract to detect intrapelvic pressure;
The perfusion fluid supply system according to claim 1 or 2, wherein the control unit sets a supply pressure of the perfusion fluid in the perfusion pump so that the detected intrapelvic pressure approaches a set reference value. The endoscope further includes a ureteral access sheath that is inserted from the ureter to the upper urinary tract of the patient and guides the endoscope to the upper urinary tract.
The irrigation fluid supply system according to claim 3 , wherein the supplied fluid is discharged outside the body through the ureteral access sheath. The pressure sensor includes:
an optical fiber extending in a longitudinal direction;
a first mirror formed of a half mirror formed at one end of the optical fiber;
a peripheral wall surrounding the first mirror in the major axis direction;
a diaphragm disposed at an end of the peripheral wall in the long axis direction, forming an air chamber together with the first mirror and the peripheral wall, the diaphragm being displaced within and outwardly of the air chamber by an external pressure;
a second mirror disposed on the diaphragm opposite to the first mirror;
a measurement unit that measures a change in a phase difference between light that enters the optical fiber from the other end and is reflected by the first mirror and light that enters the optical fiber from the other end and is reflected by the second mirror;
The perfusion fluid supply system according to claim 1 , further comprising: a pressure calculation unit that calculates the external pressure applied to the diaphragm based on the change in the phase difference. The perfusion fluid supply system according to claim 1 , wherein the control unit changes the supply pressure of the perfusion pump to intermittently send liquid from the perfusion pump and intermittently supply liquid to the vicinity of the tip of the endoscope. A method for operating a perfusion fluid supply system for supplying a fluid from a perfusion pump to the vicinity of a tip of an endoscope used in a state where the endoscope is inserted into a body cavity through a fluid supply channel extending to the vicinity of the tip of the endoscope within the endoscope, and discharging the supplied fluid to the outside through the body cavity, comprising:
a pressure sensor extending within the endoscope detects pressure near a tip of the endoscope;
a temperature sensor extending within the endoscope detects a temperature near a tip of the endoscope;
a control unit is operated to control the supply pressure of the perfusion fluid in the perfusion pump based on the pressure signal acquired from the pressure sensor and the temperature signal acquired from the temperature sensor, thereby controlling the supply amount of the perfusion fluid from the perfusion pump;
The control unit corrects the time change in the pressure value indicated by the pressure signal during a pressurization period, which gradually decreases with an increase in the amount of liquid supplied near the tip of the endoscope, based on the temperature signal, and controls the supply pressure by increasing or decreasing the supply pressure of the perfusion fluid in the perfusion pump so that the corrected pressure value approaches a predetermined reference value. The method for operating a perfusion fluid supply system according to claim 7 , wherein the perfusion fluid supply system is configured to discharge fluid through an access sheath that guides the endoscope into a body cavity.

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