Peristaltic-like bionic ureteral stent test system

Abstract

The application discloses a kind of quasi-peristalsis bionic ureteral stent test systems, including ring column type driver, silica gel hose, air pressure pump, spherical liquid accumulator, external liquid accumulator and intelligent terminal control equipment.The two spherical liquid accumulators and the customized silica gel hose in the test system can be completely imitated in the urinary tract system of renal pelvis-ureter-bladder.By changing the pressure applied by peristalsis loader and the driving of ring column type pneumatic driver, the silica gel hose can be subjected to one-way peristaltic force to facilitate the movement of liquid from one end to the other end.By periodically changing the working state of peristalsis loader and pneumatic driver, the transportation process of urine in ureter can be simulated.The application can well simulate the temperature and physicochemical properties of human urine by adjusting the temperature control and physicochemical property control device in the liquid accumulator.The test system can be used for degradation and antibacterial testing of clinical ureteral stents, and for developing better clinical ureteral stent products.

Description

Technical Field

[0001] This invention belongs to the field of medical device technology, specifically relating to a biomimetic ureteral stent testing system with simulated peristalsis. Technical Background

[0002] With rising living standards and an aging society, the incidence of urinary system-related diseases is increasing daily. Ureteral stents are widely used postoperatively to dilate the ureter to assist urination. However, most commercially available ureteral stents still have many problems: existing ureteral stents can be divided into two categories based on their materials: metal stents and polymer stents. Metal stents offer strong support and have low rates of stones and infection, but their strong mechanical properties can severely damage surrounding tissues. Polymer ureteral stents have better toughness and can be easily implanted minimally invasively, but they often suffer from insufficient structural support, and their surfaces are prone to bacterial adhesion, leading to infection. With the development of materials technology, many biodegradable stents have also been put into use. Biodegradable stents can reduce the pain of secondary stent removal, but stent degradation causes a rapid decrease in their mechanical properties, which, if poorly designed, can seriously affect stent performance. Therefore, regardless of the material of the ureteral stent, obtaining data on its mechanical properties and structural changes through in vitro simulation experiments is helpful in designing good stent products.

[0003] In vitro testing of ureteral stents is crucial, and current mainstream experiments typically employ immersion and fluid perfusion methods to simulate the fluid environment in which the stent resides. However, in reality, urine transport in the human ureter is not static or perfused. According to literature, urine transport relies on the peristalsis of the smooth muscle in the ureteral wall to propel fluid segmentally from the renal pelvis to the bladder, but the mechanical factors originating from the surrounding ureteral wall are often overlooked in current research. Therefore, most in vitro tests in current studies cannot accurately simulate the in vivo environment of ureteral stents. Thus, clinical research urgently needs a ureteral stent testing system that simulates peristalsis for in vitro stent simulation testing. Summary of the Invention

[0004] This application addresses the technical problem of the lack of an external stent testing device for ureteral stents capable of simulating peristalsis in the prior art, and thus provides a biomimetic ureteral stent testing system with simulated peristalsis.

[0005] The technical solution adopted by this application to solve the above-mentioned technical problems is as follows:

[0006] A biomimetic peristaltic ureteral stent testing system includes: two spherical reservoirs; a silicone tubing located between the two spherical reservoirs, with both ends of the silicone tubing connected to the two spherical reservoirs respectively; a ring-cylindrical actuator with a piston device mounted on one side of the ring-cylindrical actuator, and a peristaltic simulation loader disposed on the piston device, the ring-cylindrical actuator being driven by the piston device to perform reciprocating motion; and an external reservoir connected to the two spherical reservoirs via a circulation pipe, the external reservoir, the circulation pipe, the two spherical reservoirs, and the silicone tubing forming a circulating fluid passage, with a fluid delivery device disposed on the circulating fluid passage.

[0007] The peristaltic simulation loader uses an annular airbag surrounding the silicone tube. The outer wall of the annular airbag is made of a rigid material, and the annular airbag expands uniformly inward when inflated.

[0008] The peristaltic simulation loader includes an annular shell surrounding the silicone tube, a plurality of telescopic loading heads are arranged on the inner side of the annular shell, and a telescopic drive motor is arranged inside the annular shell, the telescopic drive motor driving the telescopic loading heads to achieve telescopic movement.

[0009] It also includes a peristaltic loading control center for controlling the peristaltic simulation loader; the peristaltic loading control center controls the pressure and cycle applied by the telescopic loading head to the silicone hose by controlling the movement of the telescopic drive motor.

[0010] The annular actuator employs a pneumatic annular drive chamber, which surrounds the silicone hose. The piston device is hermetically installed on one side of the annular drive chamber. A pneumatic device is connected to the annular drive chamber.

[0011] The silicone tubing is manufactured using 3D modeling and printing technology, and is customized to mimic the shape of the human ureter.

[0012] The piston device is configured as a ring-shaped cylinder, and a gap is provided on the side wall of the ring-shaped cylinder device.

[0013] A physicochemical property sensor is installed inside the external liquid reservoir.

[0014] It also includes a fixed bracket, on which the mounting positions of the two spherical liquid reservoirs are adjustable.

[0015] Silicone oil is applied to the outer surface of the silicone hose to reduce lateral sliding friction.

[0016] The advantages of the biomimetic peristaltic ureteral stent testing system described in this invention are as follows:

[0017] The peristaltic biomimetic ureteral stent testing system of this invention is suitable for in vitro testing of finished ureteral stents in clinical practice. It is applicable to in vitro stent testing of different shapes (single-J stents, double-J stents, etc.), materials (polymers, metals, etc.), body shapes, and testing cycles. This invention uses a ring-cylinder actuator to drive a piston, and utilizes a peristaltic simulation loader on the piston device to apply pressure to the silicone tubing, simulating the peristaltic urine delivery process of normal ureteral smooth muscle, providing more realistic in vitro simulation testing conditions. In a preferred embodiment, the peristaltic simulation loader includes an annular shell surrounding the silicone tubing. Multiple telescopic loading heads are arranged on the inner side of the annular shell, and a telescopic drive motor is arranged inside the annular shell. The telescopic drive motor drives the telescopic loading heads to achieve telescopic movement. The peristaltic simulation loader applies pressure to the internal silicone tubing by changing the length of the telescopic loading heads, forming a mechanical load; and through the pull of the piston, unidirectional peristalsis is achieved, pushing the liquid inside the silicone tubing to one side. By utilizing the peristaltic simulation of the loader / ring-type actuator's motion cycle, unidirectional periodic mechanical loading can be achieved. Simultaneously, an external reservoir controls the replenishment of liquid to achieve overall liquid circulation.

[0018] This invention, by adjusting the movement mode and cycle of the peristaltic simulation loader / ring-column actuator, can simulate the mechanical magnitude and state of ureteral peristalsis as much as possible. Therefore, it can be used to evaluate various indicators such as morphological characteristics, mechanical characteristics and degradation characteristics of ureteral stents of different designs under in vivo conditions.

[0019] Meanwhile, the design of the two spherical reservoirs in this invention takes into account the morphological characteristics of existing double-J stents. The two spherical reservoirs can better simulate the actual urine transport process, i.e., the renal pelvis-ureter-bladder, and can also better accommodate various types of ureteral stents. By adjusting the relative positions of the two spherical reservoirs on the fixed support, actual testing needs can be met; this allows for simulating tests in different patient postures, such as standing and lying down.

[0020] The biomimetic ureteral stent testing system described in this invention can monitor changes in the physicochemical properties of a liquid in real time using sensors within an external reservoir. By adding circulating test solutions with different formulations, it can simulate stent implantation testing in patients with different conditions, such as diabetes and proteinuria; it can also detect the potential impact of the stent on urine.

[0021] To make the technical solution of the biomimetic ureteral stent testing system with pseudo-peristalsis described in this invention clearer, the invention will be further described below in conjunction with the accompanying drawings and specific embodiments. Attached Figure Description

[0022] like Figure 1 The figure shown is a cross-sectional schematic diagram of the biomimetic ureteral stent testing system with pseudo-peristalsis described in this invention.

[0023] like Figure 2 The image shown is a top view of the external liquid reservoir described in this invention;

[0024] like Figure 3 The diagram shows the overall structure of the biomimetic ureteral stent testing system with the spherical reservoir in a vertical position, as described in this invention.

[0025] like Figure 4 The diagram shown is a schematic of the annular peristaltic loader with a telescopic loading head according to the present invention.

[0026] The attached figures are labeled as follows:

[0027] 1-Spherical reservoir; 2-Silicone tubing; 3-Peristaltic simulation loader; 31-Annular shell; 32-Telescopic loading head; 33-Telescopic drive motor; 4-Ring-column type actuator; 41-Piston device; 5-Negative pressure machine; 6-Secondary air pressure pump; 7-External reservoir; 71-Physicochemical property sensor; 72-Infusion pump; 8-Fixed bracket; 9-Circulation pipeline. Detailed Implementation

[0028] Example 1

[0029] This embodiment provides a biomimetic ureteral stent testing system with simulated peristalsis, such as... Figure 1 As shown, the simulated peristaltic bionic ureteral stent testing system includes:

[0030] Two spherical liquid reservoirs 1 are respectively mounted on two fixed supports 8. The fixed supports 8 are vertically extendable supports, and the spherical liquid reservoirs 1 are mounted on the extendable parts of the supports, so that the mounting positions of the two spherical liquid reservoirs 1 on the fixed supports 8 are adjustable.

[0031] A silicone tubing 2 is located between the two spherical reservoirs 1. Both ends of the silicone tubing 2 are connected to the two spherical reservoirs 1 respectively, forming a sealed communication structure. The silicone tubing 2 is detachably connected to the two spherical reservoirs 1 respectively. In this embodiment, the silicone tubing 2 is a customized silicone tubing made to simulate the structure of the human ureter.

[0032] A ring-shaped actuator 4 has a piston device 41 mounted on one side. In this embodiment, the ring-shaped actuator 4 uses a pneumatic annular drive chamber, which surrounds the silicone hose 2. The piston device 41 is hermetically installed on one side of the annular drive chamber, and the other side of the annular drive chamber is fixed to a spherical reservoir 1 at one end. A pneumatic device is connected to the annular drive chamber, including a first air pressure pump and a negative pressure pump 5 (the first air pressure pump is not shown in the drawing). The air pressure pump is connected to the annular drive chamber through an air inlet channel, and the negative pressure pump 5 is connected to the annular drive chamber through a suction pipe. In this application, the air pressure pump pumps gas into the annular drive chamber to achieve positive pressure pushing, and the negative pressure pump 5 performs suction to achieve negative pressure pullback, thereby realizing the reciprocating motion of the piston. As a preferred embodiment, the pneumatic device can be a dual-purpose pump that combines suction and suction functions. In this embodiment, a peristaltic simulation loader 3 is provided on the piston device 41, and the peristaltic simulation loader 3 is an airbag type loader. In a preferred embodiment, the piston device 41 is configured as a ring-cylindrical shape, with gaps on the side wall of the ring-cylindrical piston device 41 for observing the morphology of the support specimen inside the tube. Besides pneumatic drive, the ring-cylindrical actuator 4 can also be driven by a motor or other means. The piston can be mounted on one side of the annular drive chamber, and the reciprocating motion of the piston can be driven by a motor or other drive device.

[0033] In this embodiment, the airbag-type loader is an annular airbag surrounding the silicone hose 2, and a second air pressure pump 6 is connected to the annular airbag. The outer wall of the annular airbag is made of a rigid material. When inflated, the annular airbag expands uniformly inward. Therefore, the airbag-type loader is used to apply centripetal pressure to the silicone hose 2, and can be inflated and expanded by the second air pressure pump 6 to reduce the internal space.

[0034] The simulated peristaltic bionic ureteral stent testing system also includes an external reservoir 7. The external reservoir 7 has an inlet and an outlet, which are connected to two spherical reservoirs 1 via a circulation pipe 9. The external reservoir 7, circulation pipe 9, two spherical reservoirs 1, and silicone tubing 2 together form a circulation path. In this embodiment, an infusion pump 72 is installed inside the external reservoir 7 at the inlet. Figure 2 As shown. A physicochemical property sensor 71 is installed inside the external liquid reservoir 7 to detect the physicochemical properties of the liquid. As a preferred real-time method, a temperature control device and a pH adjustment device are also installed inside the external liquid reservoir 7.

[0035] To achieve intelligent control, the biomimetic peristaltic ureteral stent testing system is also equipped with an intelligent final control device. This device is connected to the pneumatic pump, negative pressure unit 5, infusion pump 72, physicochemical property sensor 71, temperature control device, and pH adjustment device. The intelligent final control device is equipped with an external computer, which is responsible for collecting, processing, and recording data, temperature, and pH information from the sensors, infusion pump 72, pneumatic pump, and negative pressure unit 5. It also controls the operational status of the pneumatic pump, negative pressure unit 5, infusion pump 72, temperature control device, and pH adjustment device through a controller.

[0036] The working process of the biomimetic peristaltic ureteral stent testing system described in this embodiment is as follows:

[0037] Select the patient group to be tested and customize a silicone tubing 2 of a certain specification. Assemble the silicone tubing 2 with the airbag-type loader, the ring-cylinder type actuator 4, and two spherical reservoirs 1. After completely disinfecting the internal circulation pathway, properly place the support to be tested and seal and fix the two spherical reservoirs 1 on both sides. Figure 1 As shown. Then, by adjusting the height and position of the two retractable supports, the patient's posture was simulated to meet experimental requirements, for example... Figure 3 As shown, when the two spherical reservoirs are arranged vertically, they can simulate the standing posture of a human body. After adjusting the position, the sensor and infusion device of the external reservoir 7 are activated and a suitable internal circulation fluid is added; the air pressure and frequency of the airbag-type loader and the ring-column type actuator 4 are regulated by the intelligent final control device to perform periodic loading.

[0038] In this embodiment, the simulated peristaltic bionic ureteral stent testing system uses a balloon-type loader and a ring-column type actuator 4. By controlling their parameters to apply a certain periodicity and a certain magnitude of negative pressure, a customized silicone tubing 2 can be loaded. The silicone tubing 2 can simulate the peristaltic process of ureteral smooth muscle during loading, and periodically deliver test fluid. Therefore, this system can effectively test the actual state of the ureteral stent in vivo, and can be applied to a series of test studies on changes in the mechanical properties of the ureteral stent, changes in material degradation, or biofilms, crusts, etc.

[0039] Example 2

[0040] This embodiment provides a biomimetic ureteral stent testing system with simulated peristalsis, such as... Figure 1 As shown, the simulated peristaltic bionic ureteral stent testing system includes:

[0041] Two spherical liquid reservoirs 1 are respectively mounted on two fixed supports 8. The fixed supports 8 are vertically extendable supports, and the spherical liquid reservoirs 1 are mounted on the extendable parts of the supports, so that the mounting positions of the two spherical liquid reservoirs 1 on the fixed supports 8 are adjustable.

[0042] A silicone tubing 2 is located between the two spherical reservoirs 1. Both ends of the silicone tubing 2 are connected to the two spherical reservoirs 1 respectively, forming a sealed communication structure. The silicone tubing 2 is detachably connected to the two spherical reservoirs 1 respectively. In this embodiment, the silicone tubing 22 is a customized silicone tubing 2 made by simulating the structure of the human ureter.

[0043] A ring-cylindrical actuator 4 has a piston device 41 mounted on one side. In this embodiment, the ring-cylindrical actuator 4 is a pneumatic annular drive chamber surrounding the silicone tubing 2. The piston device 41 is hermetically mounted on one side of the annular drive chamber, and the other side of the annular drive chamber is fixed to a spherical reservoir 1 at one end. A pneumatic device is connected to the annular drive chamber, including a pneumatic pump and a negative pressure machine 5. The pneumatic pump is connected to the annular drive chamber through an air inlet channel, and the negative pressure machine 5 is connected to the annular drive chamber through an air extraction pipe. This application uses the pneumatic pump to pump gas into the annular drive chamber to achieve the reciprocating motion of the piston. In this embodiment, a peristaltic simulation loader 3 is provided on the piston device 41. As a preferred embodiment, the piston device 41 is configured as a ring-cylindrical shape, and a gap is provided on the side wall of the ring-cylindrical piston device 41 for observing the morphology of the support specimen inside the tube.

[0044] In this embodiment, the peristaltic simulation loader 3 adopts a ring-shaped mechanical loading device, such as... Figure 4As shown, the mechanical loading device includes an annular outer shell 31 surrounding the silicone tubing 2. Multiple telescopic loading heads 32 are arranged on the inner annular side of the annular outer shell 31. A telescopic drive motor 33 is disposed inside the annular outer shell 31, driving the telescopic loading heads 32 to perform telescopic movements. In this embodiment, a loading device control center is connected to the peristaltic loading device and is installed inside the annular outer shell 31. The telescopic loading heads 32 can extend and retract at a set length based on the periodic drive of the telescopic drive motor 33. Therefore, the peristaltic loading device applies centripetal pressure to the silicone tubing 2. By controlling the extension and retraction of multiple heads, the internal space of the silicone tubing 2 can be reduced, simulating the peristalsis of the ureter. The peristaltic loading control center controls the pressure and movement cycle applied to the silicone tubing 2 by the telescopic drive motor 33. As a preferred embodiment, the length and number of heads of the annular mechanical loading device are not limited and can be customized according to actual conditions. As an alternative implementation, this simulation loading device can also complete the peristalsis simulation independently using a sufficiently long annular mechanical loading device 3 without setting the drive of the annular cylindrical driver 4. In this embodiment, the annular cylindrical driver 4 is set so that the telescopic pressure head on the annular mechanical loading device can provide telescopic pressure to squeeze the silicone hose while also providing driving force along the axial direction of the silicone hose, thus achieving a more accurate peristalsis simulation.

[0045] The simulated peristaltic bionic ureteral stent testing system also includes an external reservoir 7, which has an inlet and an outlet. The inlet and outlet are connected to two spherical reservoirs 1 via a circulation pipe 9, forming a circulation pathway. Figure 2 As shown, an infusion pump 72 is installed inside the external liquid reservoir 7 and located at the liquid inlet. A physicochemical property sensor 71 is installed inside the external liquid reservoir 7 to detect the physicochemical properties of the liquid. A temperature control device and a physicochemical property adjustment device are also installed inside the external liquid reservoir 7, the latter being a pH adjustment device.

[0046] The simulated peristaltic bionic ureteral stent testing system is equipped with an intelligent final control device. This device is connected to the negative pressure unit 5, the pneumatic pump, the peristaltic loading center, the infusion pump 72, and the physicochemical property sensor 71, temperature control device, and physicochemical property adjustment device. The intelligent final control device has an external computer responsible for collecting, processing, and recording data from the sensors, infusion pump 72, and loading device. It also controls the actions of the negative pressure unit 5, the pneumatic pump, and the infusion pump 72, as well as the operating status of the peristaltic simulated loading device 3, temperature control device, and physicochemical property adjustment device, through a controller. The working process of the simulated peristaltic bionic ureteral stent testing system in this embodiment is as follows:

[0047] Select the patient group to be tested and customize a silicone tubing 2 of a certain specification. Assemble the silicone tubing 2 with the peristaltic loader, the annular actuator 4, and the two spherical reservoirs 1. After completely disinfecting the internal circulation pathway, properly place the support to be tested and seal and fix the two spherical reservoirs 1 as follows. Figure 1 As shown. Then, the height and position of the two retractable supports are adjusted to simulate the patient's posture to meet the experimental requirements. The sensors and infusion set of the external reservoir 7 are activated and appropriate internal circulation fluid is added; the loading mode of the multiple telescopic drive motors 33 inside the peristaltic loader and the air pressure and frequency of the ring-column type driver 4 are controlled by the intelligent final control device to perform periodic loading.

[0048] The biomimetic peristaltic ureteral stent testing system described in this embodiment stimulates the silicone tubing 2 via a telescopic loading head 32, facilitating accurate simulation of ureteral peristalsis. This system can observe the effects on the stent under different patient conditions by altering the physicochemical properties of the simulated fluid in the external reservoir 7. Sensors record and adjust the physicochemical properties of the solution. This provides valuable clinical reference for observing the effects of functional (antibacterial, biodegradable, or anti-inflammatory) ureteral stents.

[0049] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the claims.

Claims

1. A biomimetic ureteral stent testing system with simulated peristalsis, characterized in that, include: Two spherical liquid reservoirs; A silicone tubing is located between the two spherical liquid reservoirs, with both ends of the silicone tubing connected to the two spherical liquid reservoirs respectively; A ring-cylinder actuator has a piston device mounted on one side, and a peristaltic simulation loader is mounted on the piston device. The ring-cylinder actuator uses a pneumatic annular drive chamber, which surrounds the silicone hose. The piston device is hermetically mounted on one side of the annular drive chamber. A pneumatic device is connected to the annular drive chamber. The ring-cylinder actuator drives the peristaltic simulation loader to reciprocate through the piston device. The peristaltic simulation loader uses an annular airbag surrounding the silicone hose. The outer wall of the annular airbag is made of a rigid material. When inflated, the annular airbag expands uniformly inward to apply centripetal pressure to the silicone hose. An external liquid reservoir is connected to two spherical liquid reservoirs via a circulation pipe. The external liquid reservoir, the circulation pipe, the two spherical liquid reservoirs, and the silicone hose form a circulating fluid passage. A fluid delivery device is provided on the circulating fluid passage.

2. The biomimetic ureteral stent testing system with simulated peristalsis according to claim 1, characterized in that, The peristaltic simulation loader includes an annular shell surrounding the silicone tube, a plurality of telescopic loading heads are arranged on the inner side of the annular shell, and a telescopic drive motor is arranged inside the annular shell, the telescopic drive motor driving the telescopic loading heads to achieve telescopic movement.

3. The biomimetic ureteral stent testing system according to claim 2, characterized in that, It also includes a peristaltic loading control center for controlling the peristaltic simulation loader; the peristaltic loading control center controls the pressure and cycle applied by the telescopic loading head to the silicone hose by controlling the movement of the telescopic drive motor.

4. The biomimetic ureteral stent testing system according to any one of claims 1-3, characterized in that, The silicone tubing is manufactured using 3D modeling and printing technology, and is customized to mimic the shape of the human ureter.

5. The biomimetic ureteral stent testing system with simulated peristalsis according to claim 4, characterized in that, The piston device is configured as a ring-shaped cylinder, and a gap is provided on the side wall of the ring-shaped cylinder device.

6. The biomimetic ureteral stent testing system with simulated peristalsis according to claim 5, characterized in that, A physicochemical property sensor is installed inside the external liquid reservoir.

7. The biomimetic ureteral stent testing system according to claim 6, characterized in that, It also includes a fixed bracket, on which the mounting positions of the two spherical liquid reservoirs are adjustable.

8. The biomimetic ureteral stent testing system according to claim 7, characterized in that, Silicone oil is applied to the outer surface of the silicone hose to reduce lateral sliding friction.

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