Quantitative evaluation device for ligation techniques

Abstract

To provide a device that can objectively and quantitatively evaluate the effectiveness of ligation techniques. [Solution] This is achieved by a quantitative evaluation device 1 for ligation techniques, which comprises a ligation section 2 that is elastic and can be tied by a thread member 20, a force sensor 6 that measures the force applied when the ligation section 2 is tied, a pressure sensor 9 that measures the pressure applied by the thread member to the ligation section 2, a camera 13 that records a video to measure the time required for the ligation operation, and a computer 7 that receives and processes signals from both sensors 6 and 9 and the camera 13, and records this information.

Description

Technical Field

[0001] The present invention relates to an apparatus for quantitatively evaluating the effectiveness of ligation techniques.

Background Art

[0002] In surgical procedures, the ligation technique of tying a thread is one of the most basic ones. For effective ligation in surgery, three conditions are required: (1) the knot does not loosen (effectiveness), (2) the tissue is not damaged (safety), and (3) speed (rapidity). Regarding how to actually perform the ligation technique, there are various theories and methods, and surgeons are implementing the ligation technique based on their respective concepts. Due to such a situation, there is no consistent data or theory as a whole, and it is considered that it takes several years or more to acquire the ligation technique. Conventionally, regarding the evaluation of the ligation technique, since the rapidity can be easily evaluated, it is routinely performed. In recent years, efforts have been made to evaluate the ligation technique (Patent Documents 1-4. Non-Patent Documents 1-3).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Non-Patent Documents

[0004]

Non-Patent Document 1

[0005] Patent Document 1 describes a technique for evaluating the force applied to forceps and muscle movement during a procedure using a pressure sensor and an electromyograph, but it only analyzes the movements during the procedure and is insufficient for quantitative evaluation or scoring of the results. Patent Document 2 concerns the evaluation of ligation using a 3-axis force measurement sensor, but it was not possible to evaluate its effectiveness. Patent Document 3 describes a technique for evaluating the effectiveness of ligation from images, but it is not a technique for direct measurement and is limited to endoscopic surgery, thus having limited applicability. Patent Document 4 describes a technique for evaluating sutures using image analysis and an optical sensor, but it is limited to sutures only, and the evaluation items are also limited. Furthermore, Non-Patent Documents 1-3 all evaluate the safety and speed of ligation, and did not provide a quantitative evaluation of effectiveness. Thus, no technology was found that could objectively and quantitatively evaluate the effectiveness of ligation techniques. This invention has been made in view of the above circumstances, and its purpose is to provide a device that can objectively and quantitatively evaluate the effectiveness of ligation techniques. [Means for solving the problem]

[0006] A quantitative evaluation device for ligation techniques according to the invention for solving the above problems is characterized by comprising: a ligation section that is elastic and can be tied with a thread member; a force sensor for measuring the force when the ligation section is tied; a pressure sensor for measuring the pressure at which the thread member tightens the ligation section; and a computer that receives and processes signals from both sensors, records this information, measures the time required for the ligation operation, and records the content of the ligation operation. According to the above invention, the force applied by the thread member when tying the knot, the pressure exerted by the thread member on the knot, and the time required for tying can be measured and recorded, thus allowing for an objective and quantitative evaluation of the effectiveness of the tying technique. Furthermore, in the above invention, the ligation portion is provided on a hollow ligation tube having a hole that opens in the axial direction, with one end of the ligation tube being closed to form a closed end and the other end being connected to the first connecting portion of the differential pressure sensor, which is the pressure measuring sensor, to form a connected end, while one end of a comparison tube is connected to the second connecting portion of the differential pressure sensor, and the other end of the comparison tube is closed. In this case, it is preferable that both tubes are provided as a plurality of attachments with different hardnesses.

[0007] According to the above invention, the pressure tightening the ligation portion can be measured by a differential pressure sensor, which is a pressure measuring sensor. Furthermore, both tubes can be changed according to the hardness of the part to be ligated. Furthermore, in the above invention, it is preferable to further include a camera that takes a video for measuring the time required for the thread member to tie the knotting portion, and the signal from the camera is transmitted to and processed by the computer, and this information is recorded by the computer. Furthermore, in the above invention, it is preferable that a temperature difference reducing member is provided between the ligation portion of the ligation tube and the connecting end, and is provided between the comparison tube and the ligation tube, having a higher thermal conductivity than the thermal conductivity of both tubes in order to reduce the temperature difference between the two tubes. According to the above invention, the temperature difference reducing member reduces the temperature difference between the two tubes, so that the pressure of the ligation by the thread member can be measured more accurately. In other words, fluctuations in the internal pressure of the tube due to changes in ambient temperature or temperature changes around the ligation part become noise during measurement, but since the pressure in the ligation tube and the comparison tube connected to both ends of the differential pressure sensor fluctuates similarly, the noise can be reduced.

[0008] Furthermore, in addition to being usable for conventional surgical procedures, the above invention is preferably used for robotic surgery or laparoscopic surgery. Furthermore, in the above invention, it is preferable that the ligation tube and the comparison tube are formed from the same material. Since the ligation tube and the comparison tube are made from the same material, their specific heats are identical. This allows for a further reduction in the temperature difference between the two tubes, enabling more accurate pressure measurement. Furthermore, an evaluation method relating to another invention is preferably an evaluation method that uses the evaluation apparatus described above and comprises: (1) a data recording step of measuring the force with which the thread member binds the knotting portion and the pressure with which the thread member tightens the knotting portion at predetermined time intervals and recording this data; (2) a phase determination step of determining the time for Phase 1 of creating a knot, Phase 2 of gripping the thread member, and Phase 3 of performing the knotting operation based on the data; and (3) a data processing step of determining the average value, maximum value, and number of peaks based on the force data for each of the Phases 1 to 3, and determining the final pressure and maximum pressure based on the pressure data. [Effects of the Invention]

[0009] According to the present invention, quantitative evaluation of ligation techniques becomes possible, which is useful for verifying and elucidating ligation technique theory. Further, it can be utilized for more effective training of trainee doctors. Furthermore, by quantitatively evaluating ligation techniques using special instruments such as robotic surgery and endoscopic surgery, performance improvement of the instruments can be expected.

Brief Description of the Drawings

[0010] [Figure 1] It is a configuration diagram of a quantitative evaluation device for ligation techniques in the present embodiment. [Figure 2] It is the algorithm of the software of the present embodiment. [Figure 3] It is a chart showing the forces in the x, y, and z-axis directions and their combined force extracted from the measurement results of the pressure and three-axis force sensors. [Figure 4] It is a chart when quantitatively evaluating the ligation techniques of three persons, PGY-1, PGY 5, and PGY 10. [Figure 5] It is a graph showing the average value (A) and maximum value (B) of the force during ligation operations of three persons, PGY-1, PGY 5, and PGY 10. [Figure 6] It is a graph showing the number of force peaks during ligation operations of three persons, PGY-1, PGY 5, and PGY 10. [Figure 7] It is a graph showing the maximum pressure (A), final pressure (B), and maximum pressure - final pressure (C) during ligation operations of three persons, PGY-1, PGY 5, and PGY 10. [Figure 8] It is a graph showing the time taken for ligation operations of three persons, PGY-1, PGY 5, and PGY 10. [Figure 9] It is a graph showing the maximum pressure, final pressure, and maximum pressure - final pressure (pa) for evaluating the effectiveness when quantitatively evaluating the ligation techniques for a total of eight subjects, three PGY-1s, one PGY 2, one PGY 5, one PGY 8, and two PGY 10s.

Modes for Carrying Out the Invention

[0011] Next, embodiments of the present invention will be described with reference to the figures and tables, but the technical scope of the present invention is not limited to these embodiments, and it can be implemented in various forms without changing the gist of the invention. <Configuration of a quantitative evaluation device for ligation techniques> Figure 1 shows the configuration of the quantitative evaluation device 1 for ligation techniques in this embodiment (hereinafter simply referred to as "evaluation device 1"). The evaluation device 1 is provided with a ligation tube 3 equipped with a ligation section 2 that can be ligated by a ligation thread (thread member) 20. Both ends of the ligation section 2 are held by two holders 4, and each holder 4 is provided on a jig 5. On the back side of the jig 5, a force sensor 6 is provided to measure the force applied when the ligation section 2 is ligated by the thread 20. The force sensor 6 is a "three-axis force sensor" that can be separated into three axes, X, Y, and Z, and measure the force applied in each direction. The force sensor 6 is connected to a computer 7, which receives signals from the sensor and processes them with predetermined software, and also records the information.

[0012] The ligation tube 3 is elastic and hollow, with an axially open hole, and one end of it is a closed end 3A, which is closed by a closing member 8. The other end of the ligation tube 3 is a connecting end 3B, which is connected to the primary side connecting part 9A of the differential pressure sensor 9. The connecting end 10B of the comparison tube 10 is connected to the secondary side connecting part 9B of the differential pressure sensor 9. The comparison tube 10 is made of the same material (material, inner diameter, and outer diameter) as the ligation tube 3 and has the same specific heat per unit mass. The other end of the comparison tube 10 is a closed end 10A, which is closed by a closing member 11. The differential pressure sensor 9 is connected to the computer 7 and detects the minute pressure difference that occurs between the primary side connection part 9A and the secondary side connection part 9B, and transmits this pressure difference as an electrical signal to the computer 7. In the ligation tube 3, a temperature difference reducing member 12 is provided between the comparison tube 10 and the ligation tube 3, between the ligation portion 2 and the connecting end 3B. This temperature difference reducing member 12 has a higher thermal conductivity than the thermal conductivity of both tubes 3 and 10, and acts to reduce the temperature difference between the two tubes 3 and 10 as quickly as possible. Such a temperature difference reducing member 12 can be formed as a thin film or double-sided tape made of materials such as diamond, silver, copper, gold, aluminum, or iron.

[0013] Furthermore, a camera 13 is provided near the ligation section 2 to measure the time required for the operation of ligating the ligation section 2 with a thread member, and to record a video of the operation to record the time required for the operation and the details of the operation. The computer 7 can receive electrical signals from the force measurement sensor 6, the differential pressure sensor 9, and the camera 13, process them using predetermined software, and record this information. As described above, with the configuration of this embodiment, the differential pressure sensor 9, which is a pressure measuring sensor, can measure the pressure tightening the ligation portion 2. At the same time, the temperature difference reducing member 12 reduces the temperature difference between the two tubes 3 and 10, thereby reducing the noise of internal pressure changes due to temperature changes in the ligation tube, and allowing for more accurate measurement of the pressure being applied by the thread member. Furthermore, since the ligation tube 3 and the comparison tube 10 are made of the same material, the temperature difference between the two tubes 3 and 10 can be further reduced (compared to when they are made of different materials), allowing for more accurate pressure measurement. The effectiveness of the ligation can be evaluated by measuring the internal pressure of tube 3. Furthermore, the deformation of tube 3 during ligation is very small, and even a slight change in the temperature of the air inside tube 3 (for example, around 0.02°C) seems to affect the detection. Therefore, this problem can be solved by connecting tubes 3 and 10 made of the same material to the high-pressure and low-pressure sides of the differential pressure sensor 9, and then bringing tubes 3 and 10 into contact with each other via the temperature difference reducing member 12.

[0014] <Overview of Software Algorithms> Figure 2 shows the software algorithm for analyzing the data acquired by the evaluation device 1 described above. First, the software is initialized (S100). Here, the sampling rate of the measurement data (samples / sec), the parameters of the low-pass filter (e.g., Butterworth filter, order, threshold, etc.), and the parameters for peak detection (e.g., height, threshold, distance (number of samples), prominence, width, etc.) are set. Next, the force with which the thread 20 binds the knotting portion 2 and the pressure with which the thread 2 tightens the knotting portion 2 are measured at predetermined time intervals set in S100, and these data are recorded (S110: data recording step). Next, the recorded data is used to determine the time for the knot-making phase (Phase 1), the thread member-grasping phase (Phase 2), and the tying operation phase (Phase 3) (S120: Phase determination process). This process may be determined automatically by software, or it may be determined manually, incorporating the operator's subjective judgment. Next, in each of Phases 1 to 3, the average value, maximum value, and number of peaks are calculated based on the force data (S130: data processing step), and the final pressure and maximum pressure are calculated based on the pressure data (S140: data processing step). Either S130 or S140 can be performed first. In this way, various numerical values ​​can be automatically calculated from the recorded data.

[0015] <Measurement Test 1> Next, the ligation technique of three subjects was objectively measured using the evaluation device 1 configured as described above. The three subjects were PGY-1 (medical student: not a doctor but having completed the prescribed training), PGY-5 (a surgeon with 5 years of experience), and PGY-10 (a surgeon with 10 years of experience). For each subject, using evaluation device 1, ligation was performed up to the 8th step using 2-0 silk thread in the usual manner. Quantitative evaluation of the ligation technique was performed for 5 of these ligation operations using force measurement sensor 6, differential pressure sensor 9, and camera 13. Table 1 shows a summary of the evaluation items and statistical analysis.

[0016] [Table 1]

[0017] As shown in Table 1, ligation was evaluated by composite force (mean, maximum, and number of peaks), tightness (final pressure and maximum pressure), and time (ligation time). Each data point is shown in a box plot, and statistical analysis of the data between the two groups was performed using Student's t-test or Welch's t-test. Table 2 summarizes the typical knot-tying methods of each subject. As shown in Table 2, differences were observed in the typical knot-tying methods of each subject.

[0018] [Table 2]

[0019] Figure 3 shows a representative chart illustrating the measured pressure, forces in the x, y, and z axes, and their combined force. The horizontal axis represents time (t). The process is divided into Phase 0 (preparation), Phase 1 (knot creation), Phase 2 (thread gripping), Phase 3 (tightening the knot), and then Phases 1 through 3 are repeated. Figure 3 shows the chart for the first knot. Figure 4 shows the charts for the first ligation for PGY-1, PGY-5, and PGY-10, starting from Phase 0 and repeating Phases 1 through 3. The average, maximum, and number of peaks were calculated from the combined force data, and the final and maximum pressure were calculated from the pressure data. The force data was displayed automatically (without any special processing). For the pressure data, if noise due to temperature changes was detected, correction was performed using data from before the start of ligation (when the thread was not being touched). The phase transitions were manually analyzed based on the video to determine when each phase switched.

[0020] For determining the number of peaks, the following algorithm was used. Specifically, using the Python library sci-py, a low-pass filter (Butterworth filter, order 8, threshold 16 Hz) was applied, and then the find_peaks function was executed with the following settings. The sampling rate was set to 1000 samples / sec. height = 0.3 (N) threshold = None distance= 5 (samples) prominence = 0.4 width = 1 (samples) Figure 5 shows the mean and maximum force data (N) as data related to ligation safety. The data is shown as the mean ± standard deviation (SD) of five consecutive measurements (the same applies to Figures 6 to 8). In the figure, "**" indicates a significant difference at a significance level of less than 1% (p<0.01), "*" indicates a significant difference at a significance level of less than 5% (p<0.05), and NS (Not Significant) indicates no significant difference. The mean force was in the order of PGY 5 > PGY -1 > PGY 10, and the maximum force was in the order of PGY 10 > PGY 5 > PGY -1. Furthermore, a significant difference (p<0.01) was observed in the mean force between PGY -1 and PGY 5. A significant difference (p<0.05) was observed in the maximum force between PGY -1 and PGY 5.

[0021] Figure 6 shows data on the number of force peaks as an indicator of ligation safety. The number of force peaks was in the order of PGY 5 ≥ PGY -1 > PGY 10. A significant difference (p<0.01) was observed between PGY -1 and PGY 10. Figure 7 shows data on the effectiveness of ligation, including the maximum pressure, final pressure, and maximum-to-final pressure (Pa) within the tube. The order of maximum pressure was PGY 5 > PGY 10 > PGY -1, the order of final pressure was PGY 5 ≥ PGY 10 > PGY -1, and the order of maximum-to-final pressure was PGY 10 ≥ PGY 5 > PGY -1. Furthermore, a significant difference (p<0.01) was observed in the maximum pressure between PGY -1 and PGY 10. A significant difference (p<0.01) was observed in the final pressure between PGY -1 and PGY 5. A significant difference (p<0.01) was observed in the maximum-to-final pressure between PGY -1 and PGY 10. Figure 8 shows data on the speed of ligation, specifically the time (seconds) per ligation. The time required for ligation was in the order of PGY-1 > PGY-5 > PGY-10. Significant differences (p<0.05) were observed between PGY-1 and PGY-5, and between PGY-5 and PGY-10. Table 3 summarizes the findings obtained from the above results. As shown in Table 3, the effectiveness of the ligation technique was objectively and quantitatively evaluated in three subjects by measuring and recording the force applied by the thread member when ligating the knot, the pressure exerted by the thread member on the knot, and the time required for ligation.

[0022] [Table 3]

[0023] <Measurement Test 2> Next, several new subjects were recruited, and a quantitative evaluation of the ligation technique was performed on a total of eight subjects: three PGY-1 subjects, one each of PGY 2, PGY 5, and PGY 8 subjects, and two PGY 10 subjects, according to the method of <Measurement Test 1> described above. Figure 9 shows the results, specifically the maximum pressure, final pressure, and maximum pressure-final pressure (Pa), which are used to evaluate the effectiveness of ligation. These results indicate that the effectiveness of ligation techniques increases with experience as a surgeon gains more experience.

[0024] Thus, this embodiment provides a device that can objectively and quantitatively evaluate the effectiveness of ligation techniques. Furthermore, the present invention can also be implemented as follows. (1) In this embodiment, the ligation portion 2 is provided as a ligation tube 3, but according to the present invention, the ligation technique can be used not only for tubular blood vessels but also for evaluating the ligation technique of tissue fragments. (2) In this embodiment, a temperature difference reducing member 12 was interposed between the two tubes 3 and 10 to bring them into contact, but according to the present invention, it is not necessary to provide such a member. (3) In this embodiment, the force measurement sensor 6 is a three-axis force measurement sensor, but according to the present invention, it may be a force measurement sensor that measures the combined force. [Explanation of symbols]

[0025] 1...Quantitative evaluation device for ligation technique, 2...Lifting section, 3...Lifting tube, 3A...Closing end, 3B...Connecting end, 6...Force measurement sensor, 7...Computer, 9...Differential pressure sensor, 9A...Primary side connecting section, 10...Comparison tube, 10A...Closing end, 10B...Connecting end, 12...Temperature difference reduction member, 13...Camera, 20...Thread member

Claims

1. A quantitative evaluation device for ligation techniques comprising: a ligation section that is elastic and can be tied with a thread member; a force sensor for measuring the force applied when the ligation section is tied; a pressure sensor for measuring the pressure exerted by the thread member on the ligation section; and a computer that receives and processes signals from both sensors, records this information, measures the time required for the ligation operation, and records the details of the ligation operation.

2. The ligation portion is provided on a hollow ligation tube having an axially open hole, one end of the ligation tube is closed to form a closed end, and the other end is connected to a first connecting portion of a differential pressure sensor which is a pressure measuring sensor to form a connected end, while one end of a comparison tube is connected to a second connecting portion of the differential pressure sensor, and the other end of the comparison tube is closed, as described in claim 1.

3. The quantitative evaluation device for ligation techniques according to claim 2, wherein the two tubes are provided as a plurality of attachments with different hardnesses.

4. The quantitative evaluation device for a ligation procedure according to claim 2, wherein a temperature difference reducing member is provided between the comparison tube and the ligation tube, and has a higher thermal conductivity than the thermal conductivity of both tubes in order to reduce the temperature difference between the two tubes, between the ligation portion of the ligation tube and the connecting end.

5. Furthermore, the quantitative evaluation device for ligation techniques according to claim 1 is further equipped with a camera that takes a video for measuring the time required for the thread member to ligate the ligation portion, the signal from the camera is transmitted to and processed by the computer, and this information is recorded by the computer.

6. A quantitative evaluation device for ligation techniques according to any one of claims 1 to 5, the quantitative evaluation device for ligation techniques used in robotic surgery or laparoscopic surgery.

7. An evaluation method using a quantitative evaluation device for ligation techniques according to any one of claims 1 to 5, comprising: (1) a data recording step of measuring the force with which the thread member ligates the ligation portion and the pressure with which the thread member tightens the ligation portion at predetermined time intervals and recording this data; (2) a phase determination step of determining the time for Phase 1 of creating a knot, Phase 2 of grasping the thread member, and Phase 3 of performing the ligation operation based on the data; and (3) a data processing step of determining the average value, maximum value, and number of peaks based on the force data for each of the Phases 1 to 3, and determining the final pressure and maximum pressure based on the pressure data.

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