System for temperature monitoring when performing laser-based intracorporeal lithotripsy
By installing flow and temperature sensors in the endoscopic arrangement, combined with computer analysis and processing, the temperature and liquid rate in laser lithotripsy are monitored in real time, and the problem of local overheating in laser lithotripsy is solved, achieving operational safety and permission Reduced review costs.
Patent Information
- Application Number
- CN202410734869.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2019-07-11
- Filing Date
- 2020-07-07
- Publication Date
- 2024-12-31
AI Technical Summary
When performing laser-based in vivo lithotripsy, the prior art is difficult to effectively monitor and prevent tissue damage caused by local overheating, and the existing medical technology licensing review and certification process is time-consuming and expensive.
By installing flow sensors and temperature sensors in the endoscopic arrangement, combined with computer units for analysis and processing, the laser power, flushing liquid rate and temperature are monitored in real time, signal warnings are provided to prevent overheating, and flushing liquid rate can be adjusted to keep tissue safe .
Real-time monitoring and prevention of local overheating during laser lithotripsy is achieved, ensuring operational safety, avoiding irreversible tissue damage, and reducing the cost and time overhead of medical technology licensing review and certification.
Smart Images
Figure CN119214785A_ABST
Abstract
Description
[0001] This divisional application is a divisional application of an invention patent application with an application date of July 7, 2020, application number 202080057106.9, and invention name “System for temperature monitoring during laser-based intracorporeal lithotripsy”. Technical Field
[0002] The invention relates to a system for temperature monitoring when performing laser-based intracorporeal lithotripsy, in which an endoscopic arrangement is used, the endoscopic arrangement comprising a working channel for an optical waveguide, the optical waveguide being optically coupled to a laser on the proximal side and having a light exit opening on the distal side, the flushing liquid channel being open on the distal side to the region of the light exit opening and being fluidically connected to a flushing liquid container on the proximal side. Background Art
[0003] Intracorporeal lithotripsy is a minimally invasive surgical method for fragmenting stones, such as gallstones, urinary stones or kidney stones, which accumulate primarily in the excretory ducts of the organs involved and can cause severe pain or other medical problems. Among the various known intracorporeal lithotripsy methods, laser-induced lithotripsy has established itself as a method in which energy-rich laser radiation is applied via optical fibers in the form of laser pulses to the location of the stone to be fragmented. The interaction of the laser pulses with the intracorporeal medium forms vapor bubbles, whose pulsed expansion generates pressure waves that cause the stone to fragment. Depending on the size of the stone fragments, the stone fragments produced in laser-induced lithotripsy can be discharged naturally or can be removed with the aid of a suitably designed endoscopic gripping tool.
[0004] To perform laser-based lithotripsy, an endoscope is used, which is provided with at least one working channel for a light conductor, which is optically coupled to the laser on the proximal side and has a light exit opening on the distal side. In order to be able to follow the organ entrance to the stone with the help of the endoscope and to place as little strain on the patient as possible during the treatment, such an endoscope can be designed to be flexible and pliable. In addition, such an endoscope can usually apply a flushing liquid through a working channel, which is open on the distal side to the region of the light exit opening and is fluidically connected on the proximal side to a flushing liquid delivery device and a flushing liquid container, the flushing liquid delivery device preferably being in the form of a flushing sprayer and / or a controllable or adjustable delivery pump.
[0005] With such an endoscope arrangement, which comprises an endoscope and the above-mentioned peripheral instruments attached to it, it is necessary to coordinate the laser power applied in vivo at the location of the stone to be fragmented and the amount of rinsing liquid discharged distally into the rinsing channel in such a way that, on the one hand, effective stone fragmentation is achieved and, on the other hand, no local overheating of the surrounding tissue area due to the laser occurs, which could lead to irreversible tissue damage. In most cases, such endoscopes have additional fiberglass optics for the operator or an imaging sensor on the endoscope injector, which must be optically cleared by means of a metered supply of rinsing liquid in order to always ensure a free viewing angle for the operator for monitoring the fragmentation process.
[0006] Document US2018 / 0055568 A1 describes an endoscope arrangement according to this category for performing laser-based lithotripsy, wherein an associated flushing liquid delivery unit of the endoscope arrangement can be adjusted as a function of at least one parameter influencing the lithotripsy process, i.e., the flushing rate can be influenced as a function of the lithotripsy process. In addition to optical monitoring of the fragmentation process, the known endoscope arrangement also provides a temperature sensor mounted on the distal end of the endoscope, which temperature sensor can detect the distal temperature of the liquid surrounding the temperature sensor, and the flushing liquid delivery unit adjusts the flushing liquid rate based on the distal temperature.
[0007] In the known medical endoscope according to document DE 20 2017 102 316 U1, which is suitable for performing laser-based lithotripsy, an ambient temperature sensor is also arranged at the distal end region of the endoscope for the purpose of temperature measurement.
[0008] Such sensor-equipped endoscopic arrangements constitute highly complex medical instruments that are subject to lengthy and extensive medical technology approval examinations. Summary of the invention
[0009] The object of the present invention is to expand a system for temperature monitoring during laser-based intracorporeal lithotripsy, in which an endoscope arrangement is used, which includes a working channel for an optical waveguide, which optical waveguide is optically coupled to a laser on the proximal side and has a light exit opening on the distal side, and a flushing liquid channel, which opens open on the distal side into the region of the light exit opening and is fluidically connected to a flushing liquid container on the proximal side, in such a way that a monitored intracorporeal lithotripsy can also be performed with a standard endoscope arrangement of this type without the need for the costly and time-consuming medical technical approval or certification. Measures must be found by which endoscopes, laser systems and other medical technical devices (e.g. flushing liquid devices for passive and active flushing) that are already in use and are basically designed to be suitable for laser-based lithotripsy can be retrofitted with appropriately selected components in order to safely exclude possible thermally induced tissue degradation in the immediate vicinity of the stone fragmentation site.
[0010] The achievement of the object on which the invention is based is described in claim 1. Features which develop the inventive concept in an advantageous manner are the subject matter of the dependent claims and can be gathered from the further description, in particular with reference to the exemplary embodiments.
[0011] In general, in vivo laser applications can only be performed briefly, i.e. for a few seconds, without irrigation, i.e., without any irrigation liquid supply in the region of the distal light exit opening of the light guide, because without any cooling due to irrigation, a critical temperature of approximately 42° C. is reached and exceeded, from which the surrounding tissue is irreversibly thermally damaged. Irrigation is therefore indispensable during laser-based lithotripsy in order to ensure adequate cooling.
[0012] Based on numerous experiments that have been carried out for laser-based lithotripsy, it is possible to find a reliable numerical or theoretical correlation between the laser power applied in vivo, the irrigation liquid rate, the irrigation liquid temperature and the temperature occurring in vivo during the application of the laser pulses.
[0013] Based on this knowledge, the following possibility is opened up: a known endoscope known per se with at least one working channel for an optical waveguide, which optically couples a laser on the proximal side and has a light exit opening on the distal side, and comprises a flushing liquid channel, which is designed separately from the working channel or is designed in unison with the working channel and which opens open on the distal side into the region of the light exit opening and is fluidically connected on the proximal side to an optional flushing liquid delivery unit and a flushing liquid container, is combined with a modular unit designed according to the solution of the invention in such a way that the modular unit comprises at least one flow sensor and at least one temperature sensor, which can be mounted, preferably releasably fixedly mounted, along the flushing liquid channel and / or a supply line fluidically connected to the flushing liquid channel, along the extracorporeal region in which the endoscope is arranged. The flow sensor is designed and arranged in such a way that the flushing flow rate can be ascertained in a contactless manner with the flushing liquid. Likewise, the temperature sensor is designed and installed along the flushing liquid channel and / or a supply line fluidically connected to the flushing liquid channel in such a way that the flushing liquid temperature can be ascertained in a contactless manner with the flushing liquid.
[0014] Furthermore, the module unit comprises either an input device, via which operating parameters of the laser can be input and transmitted to a computer unit connected to the input device, or an interface, via which the operating parameters of the laser can be directly transmitted. The operating parameters of the laser preferably relate to the laser power, wherein the laser power applied at the location of the light exit opening can be calculated via the laser pulse frequency and the single pulse energy.
[0015] Furthermore, an evaluation unit is implemented in the computer unit, which numerically ascertains the temperature that occurs in the body at the location of the light exit opening during laser-based lithotripsy based on the sensor-detected irrigation flow rate, the sensor-detected temperature of the irrigation liquid and the ascertained laser power used in the body. A comparator unit is arranged separately from the computer unit or integrated into the computer unit, which compares the ascertained temperature with an adjustable threshold value (e.g. 42° C.) and generates a signal if the threshold value is exceeded.
[0016] Furthermore, in a preferred embodiment, a signal unit is provided which is connected to the comparator unit in a wireless or wired manner and which can be presented in a tactile, acoustic and / or visually perceptible manner via a signal generated by the comparator unit. The physician performing the lithotripsy is warned of possible overheating effects in the body by means of the signal unit, so that the lithotripsy treatment can be interrupted in this way or other measures can be taken.
[0017] The modular unit according to the present solution, which is preferably designed as a retrofit set or retrofit kit, comprises only components that can be installed in a modular manner on the endoscope arrangement in use without impairing the basic functionality of the endoscope arrangement. The system according to the present solution thus forms a safety system that assists the physician when performing laser-based lithotripsy and by which the physician receives reliable and reliable information in order to be able to perform the lithotripsy procedure in an efficient and patient-friendly manner.
[0018] The only information required for this is the current temperature of the irrigation fluid introduced into the body via the endoscopic arrangement with the aid of a working channel or irrigation fluid channel, the laser power applied at the location of the stone to be fragmented, and the irrigation rate of the irrigation fluid introduced into the body via the working channel or irrigation fluid channel at the location of laser application.
[0019] The sensors required for the rinsing liquid temperature and the rinsing rate are components that can be fixedly attached to the rinsing liquid channel and / or to a supply line fluidically connected to the rinsing liquid channel in a releasable manner, and are installed in an area of the endoscope arrangement that is not introduced into the body in vivo. A flow sensor in the form of an ultrasonic sensor is therefore preferably suitable as a sensor for determining the rinsing flow rate. A temperature sensor in the form of an infrared sensor is suitable for detecting the rinsing liquid temperature.
[0020] In order to determine the temperature that develops at the location of the light exit opening of the optical waveguide, operating parameters that can be predefined at the laser are required, which relate to the laser pulse frequency and the energy per pulse. These operating parameters can be provided via a suitably designed input device, for example via a keyboard or by means of an input device that operates via voice control or via a direct interface on the laser of a computer unit.
[0021] The evaluation unit implemented in the computer unit determines the temperature T which is established at the location of the light exit opening in the following manner based on the following formula:
[0022]
[0023] In numerous experiments performed in vitro and ex vivo, a numerical dependence of the temperature developed in vivo at the site of laser application during laser-based lithotripsy on the applied laser power, the irrigation flow rate and the temperature of the irrigation fluid has been demonstrated.
[0024] Although the above algorithm is a simplified formula relationship, it is able to predict the final in vivo temperature that can be expected at the site of stone fragmentation during laser-based lithotripsy with sufficient accuracy, thereby making it possible to exclude local overheating, which can cause irreversible tissue damage in the immediate vicinity of the site of laser-based lithotripsy.
[0025] If the laser does not have an interface for displaying the operation of the laser, the module unit additionally comprises a microphone unit for detecting an acoustic signal indicating the operation of the laser, which signal is transmitted to the evaluation unit for signal evaluation synchronously with the actual laser operation time. The laser thus generates an unambiguously detectable acoustic signal during the operation of the laser, which acoustic signal can be detected in a time-resolved manner by means of the microphone unit.
[0026] Although the physician responsible for performing the lithotripsy is the sole decision maker when performing laser-based lithotripsy, in another embodiment, the modular unit constructed according to the present solution can include an additional (i.e. in addition to the signaling unit that appears in an acoustic, visual and / or tactile manner) emergency stop switch that can trigger an interruption of the current supply at least for the laser source.
[0027] In another embodiment, the modular unit that can be matched to the endoscope arrangement additionally has a unit for detecting the filling state of the amount of flushing liquid contained in the flushing liquid container. The unit is designed as a sensor arranged on the flushing liquid container and / or in the form of a software-based analysis algorithm implemented in a computing unit, which determines the current filling state based on the flushing flow rate detected by sensor and the measured duration of flushing liquid discharge. The sensor signal representing the filling state or the numerically determined filling state value representing the filling state is used at least to monitor the actual state and to predict the duration until the flushing liquid container position is completely emptied or to warn when a minimum residual amount is reached. The information obtained thereby is displayed to the doctor performing the treatment by a suitable display in a manner that can be perceived optically or acoustically. The display can be realized by a signal unit or by an additional display, by which the doctor performing the lithotripsy is warned of possible overheating effects in the body.
[0028] Another embodiment enables additional monitoring of the temperature of the supplied rinsing liquid. For this purpose, the temperature (T S ) is preferably displayed as an alphanumeric value on the visual instrument. In addition, the measured temperature is preferably provided to the comparator unit or a further comparator unit, wherein the temperature of the flushing liquid (T S) when the temperature falls below or exceeds a critical temperature value, a signal is generated which serves as a warning to the physician carrying out the treatment, for example in the case of too cold irrigation fluid, in order to avoid the risk of hypothermia of the patient.
[0029] In another possible embodiment, the flushing liquid delivery unit is provided with means by which the flushing liquid rate can be adjusted as a function of the temperature T occurring at the location of the light exit opening and / or at least one operating parameter of the laser. This opens up the possibility of actively adjusting the flushing liquid rate of the flushing liquid delivery unit in the form of a pump as a function of the applied laser power and / or the calculated temperature in the intervention area.
[0030] The system for temperature monitoring during laser-based lithotripsy according to the present solution can be used in different anatomical areas, for example in the area of the bladder, ureter or renal pelvis. Depending on the field of application, it is possible to select between different modes to match the intervention. In this case, the system offers the possibility of selecting a prostate, bladder mode, ureter mode or renal pelvis mode, which differ in definable warning limits and stored characteristic curves. This makes it possible to handle the individual risk profiles of different surgeries.
[0031] The system can therefore be used in all laser-based procedures in urology, in particular in laser lithotripsy, laser-assisted prostatectomy (HoLEP, ThuLEP), laser vaporization (PVP) and interstitial laser vaporization (ILC). BRIEF DESCRIPTION OF THE DRAWINGS
[0032] Embodiments of the present invention and industrial applicability
[0033] The single FIGURE shows an endoscope 1 having a working channel for an optical waveguide 2, which is optically coupled to a laser 3 on the proximal side and has a light exit opening 4 on the distal side. The endoscope 1 also has a flushing liquid channel 5, which is open on the distal side to the region of the light exit opening 4 and is fluidically connected to a liquid delivery unit 6 and a liquid container 7 on the proximal side. Of course, endoscopes are also known that combine the flushing liquid channel 5 with the working channel for the optical waveguide 2 into one channel. Such endoscopes, known per se, are arranged for fragmenting internal stones 8 in the manner of laser-based lithotripsy.
[0034] The system for temperature monitoring according to the present solution is a modular unit 9 which can be combined with an endoscope arrangement in its extracorporeal region, the endoscope arrangement comprising an endoscope 1, a laser 3, a liquid delivery unit 6 and a liquid container 7, and which in a preferred embodiment consists of the following components:
[0035] A flow sensor 10 is detachably fixedly mounted along the flushing liquid supply line 5, which is preferably in the form of an ultrasonic sensor. Likewise, a temperature sensor 11 for detecting the temperature of the flushing liquid is detachably fixedly mounted along the flushing liquid channel 5 or the supply line fluidically connected thereto, which is preferably in the form of an infrared sensor. The sensor signals S, T generated by the sensors 10, 11 are S The data is transmitted to the computer unit 12 via a wired connection or wirelessly.
[0036] Furthermore, an input device 13 is provided, which is preferably in the form of an interface to the laser unit for automatic transmission of operating parameters, alternatively in the form of a manually operable keyboard, via which operating parameters of the laser 3 can be input. For the operation of the laser 3, the laser pulse frequency f can be predefined by the operator. L And the single pulse energy E P It is these operating parameters that can be provided to the computer unit 12 via the input device 13 , based on which the laser power that can be applied at the location of the light exit opening 4 is calculated.
[0037] An evaluation unit 14 is implemented in the computer unit 12 and is based on the operating parameters of the laser, the flushing flow rate detected by sensor and the temperature T of the flushing liquid. S The temperature currently formed at the position of the light exit hole 4 is obtained based on the following algorithm:
[0038]
[0039] Furthermore, the determined internal body temperature T is compared with an adjustable threshold value in the comparator unit 15, which is preferably T K =42°C. Above this threshold T K In the case of K , which is supplied to a signal unit 16 which appears in a manner that is tactilely, acoustically and / or visually perceptible to the physician performing the lithotripsy.
[0040] In addition, the microphone unit 17 is connected to the computer unit 12, by means of which the activity of the laser 3 is detected, in order in this way to ensure that the data processed by the computer unit 12 and the evaluation unit 14 implemented therein and the signal S K The generation on this basis is time synchronized with the actual operation of the laser 3 .
[0041] Reference numerals list
[0042] 1. Endoscope
[0043] 2 Photoconductor
[0044] 3 Lasers
[0045] 4 light exit holes
[0046] 5 Flushing liquid channel
[0047] 6. Flushing liquid delivery unit
[0048] 7. Rinse liquid containers
[0049] 8. Stones
[0050] 9 module units
[0051] 10Flow sensor
[0052] 11 Temperature Sensor
[0053] 12 Computer Unit
[0054] 13 Input Devices
[0055] 14 Analysis and processing unit
[0056] 15 Comparator Unit
[0057] 16 signal units
[0058] 17 Microphone Unit
Claims
1. A system for providing user-perceivable feedback during laser treatment, the system comprising: a temperature sensor for determining the temperature of an irrigation fluid supplied to a surgical site; a flow sensor for determining a flow rate of an irrigation fluid supplied to a surgical site without contacting the irrigation fluid; An input device for receiving a parameter value associated with the laser source so as to apply the laser power at the location of the light exit hole; an analysis and processing unit, configured to determine a temperature at the light exit hole location based at least in part on the determined temperature, the determined flow rate and the received parameter value associated with the laser source; as well as A comparator unit is configured to provide perceptible feedback to a user when (i) the determined temperature reaches or exceeds a first predetermined threshold, and / or (ii) the determined temperature is below a second predetermined threshold.
2. The system according to claim 1, It is characterized in that The flow sensor includes an ultrasonic sensor.
3. The system according to claim 1, It is characterized in that The input device is further configured to receive a selected operating mode for performing a therapeutic laser procedure based on the anatomy of the surgical site.
4. The system according to claim 1, It is characterized in that The parameters related to the laser source include at least one of laser pulse frequency, laser pulse energy or laser pulse width.
5. The system according to claim 1, It is characterized in that The evaluation unit determines the temperature at least partially based on the following formula:
6. The system according to claim 1, It is characterized in that The user-perceivable feedback includes at least one of tactilely, acoustically, and / or visually perceivable feedback.
7. The system according to claim 1, It is characterized in that Irrigation liquid is supplied from an irrigation liquid container to the surgical site through an irrigation liquid channel, and the system further comprises a cooling unit (i) coupled to at least one of the irrigation liquid channel or the irrigation liquid container and (ii) activated or controlled by the comparator unit.
8. The system according to claim 1, It is characterized in that The irrigation liquid is supplied from the irrigation liquid container to the surgical site through the irrigation liquid passage, and the system further includes a filling state sensor for detecting a filling state of the irrigation liquid in the irrigation liquid container.
9. The system according to claim 8, It is characterized in that The filling level sensor is arranged on the flushing liquid container and / or is a software-based evaluation algorithm implemented in a computer unit which determines the filling level at least partially based on the determined flow rate and the measured duration of the flushing liquid discharge.
10. The system according to claim 9, It is characterized in that The computer unit is further designed to: (i) predict a time period until the rinsing liquid container is completely empty and / or (ii) generate a warning signal when a minimum remaining amount of rinsing liquid is reached.
11. The system according to claim 1, It is characterized in that Also included is an irrigation liquid delivery unit for adjusting an irrigation liquid flow rate based at least in part on the determined temperature and / or the received parameter value associated with the laser source.
12. The system according to claim 1, It is characterized in that The comparator unit is further configured to activate or deactivate the emergency stop mechanism.
13. The system according to claim 1, It is characterized in that At least one of the flow sensor or the temperature sensor includes a mounting kit for mounting on an endoscope.
14. The system according to claim 13, It is characterized in that The endoscope has an extracorporeal region that remains outside the patient's body during laser treatment, and at least one of a temperature sensor or a flow sensor is installed in the extracorporeal region of the endoscope.
15. A method for providing user-perceivable feedback during laser treatment, the method comprising: determining a flow rate of irrigation fluid supplied to a surgical site without contacting the irrigation fluid; receiving a parameter value of a laser system for applying laser power at a location of a light exit aperture; Determine the temperature of the flushing fluid; During the laser treatment, the temperature at the light exit hole is determined by calculation based at least in part on the determined flow rate of the irrigation liquid, the determined temperature of the irrigation liquid, and the parameter value of the laser system; as well as Perceptible feedback is provided to a user when (i) the determined temperature reaches or exceeds a first predetermined threshold, and / or (ii) the determined temperature is below a second predetermined threshold.
16. The method according to claim 15, It is characterized in that Also includes: The mode of operation used to perform the therapeutic laser procedure is selected based on the anatomy of the surgical site.
17. The method according to claim 15, It is characterized in that The parameters related to the laser source include at least one of laser pulse frequency, laser pulse energy or laser pulse width.
18. The method according to claim 15, It is characterized in that The temperature is determined based on the following formula:
19. The method according to claim 15, It is characterized in that The user-perceivable feedback includes at least one of tactilely, acoustically, and / or visually perceivable feedback.
20. The method according to claim 15, It is characterized in that Active cooling of the flushing fluid is also included.
21. The method according to claim 15, It is characterized in that Also includes: The filling state of the flushing liquid in the flushing liquid container is detected.
22. The method according to claim 21, It is characterized in that Also includes: (i) predicting the time period until the flushing liquid container is completely empty, and (ii) generating a warning signal when a minimum remaining amount of flushing liquid is reached.
23. The method according to claim 15, It is characterized in that Also includes: The irrigation liquid flow rate is adjusted based at least in part on the determined temperature and / or the received parameter value associated with the laser source.