CN110009962B - Vascular intervention operation training system based on motion scaling - Google Patents

Abstract

The application discloses a vascular intervention operation training system based on motion scaling, which comprises an operation device and a visualization device, wherein the operation device comprises a catheter, an axial operation structure for driving the catheter to axially move and a guide structure for driving the catheter to rotationally move, a first control device for controlling the operation of the axial operation structure is arranged in the guide structure, and a second control device for controlling the operation of the axial operation structure is arranged in the visualization device. The application utilizes the catheter motion scaling principle to simulate the vascular intervention operation of a surgeon, designs a reasonable operation scheme of the catheter and provides effective tactile feedback in the horizontal direction; solves the problem that the vascular wall collides with the tip of the catheter to cause vascular tissue damage due to the lack of operation experience of trained doctors in the vascular interventional operation training process.

Description

Vascular interventional surgery training system based on motion scaling

Technical field

The invention relates to a vascular interventional surgery training system, in particular to a vascular interventional surgery training system based on motion scaling.

Background technique

Currently, most catheter operation training systems for vascular interventional surgeries use virtual reality technology (VR) to simulate the operation of the catheter in the blood vessel. However, doctors lack a real blood vessel insertion environment and there is no real-time tactile feedback to remind doctors of the catheter insertion process. Whether obstacles are encountered and collisions occur. When a collision occurs without timely tactile feedback, doctors cannot react quickly to correct their operations, so it is easy to cause blood vessel damage. At the same time, the entire vascular interventional surgery process requires the doctor to operate quickly and accurately.

Most of the existing training equipment reproduces the interventional doctor's operations on the equipment in VR, and the movement speed of the catheter in VR is limited by the doctor's operation speed. When the diameter of blood vessels is small and slow and precise operation is required, the accuracy of catheter movement is limited by the resolution of human hand operation and cannot meet the requirements.

Contents of the invention

The technical problem to be solved by the present invention is that in the traditional vascular surgery training system, not only the catheter is limited by the operator's operating speed, but also the trained doctors lack operating experience. Therefore, the blood vessel wall and the catheter tip are prone to collision. The purpose is to provide motion-based zooming. The vascular interventional surgery training system solves the problem of vascular tissue damage caused by collision between the blood vessel wall and the tip of the catheter due to the lack of operating experience of trained doctors during the training of vascular interventional surgery.

The present invention is realized through the following technical solutions:

A vascular interventional surgery training system based on motion scaling includes an operating device and a visualization device. The operating device includes a catheter, an axial operating structure that drives the axial movement of the catheter, and a guide structure that drives the rotational movement of the catheter. The guide structure is provided with a control shaft. A first control device that operates toward the operating structure, and a second control device that controls the operation of the axial operating structure is provided in the visualization device.

The invention utilizes the principle of catheter motion scaling to simulate the operation of vascular interventional surgery by surgeons, designs a reasonable operation plan of the catheter, and provides effective tactile feedback in the horizontal direction; it solves the problem that the catheter in traditional vascular interventional equipment is limited by the operator's operation. disadvantages of speed and increased safety during catheter intervention. The doctor inserts the catheter into the blood vessel, mainly by operating the catheter forward and backward and clockwise or counterclockwise rotation; in the present invention, the axial forward and backward movement of the catheter is realized by the axial operating structure, and the rotational movement of the catheter is realized by the guide structure; existing The advancement and retreat of the catheter in the vascular interventional equipment is manually controlled, and the moving speed of the catheter is manually limited; the present invention changes the control device and control method for the advancement and retreat of the catheter in the axial direction. In the case of manually moving the catheter, the present invention increases A first control device and a second control device are provided. The first control device and the second control device cooperate to control the forward and backward movement of the catheter and the speed of the catheter movement. The movement of the catheter is not limited to the operator's operating speed. The guide structure in the present invention can not only control the rotational movement of the catheter in the blood vessel, but also trigger the axial operating structure through the first control device. The axial operating structure controls the axial movement of the catheter under the triggering of the guide structure. Therefore, the guide structure in the present invention The structure can not only control the rotational movement of the catheter but also the axial movement of the catheter; rotate the catheter through the guide structure and adjust the distance between the catheter tip and the blood vessel wall to maintain a safe distance between the blood vessel and the catheter; the catheter movement distance in the visualization device, The movement state and movement speed are consistent with the movement information of the axial operating structure in the operating device. The visualization device detects the distance between the catheter tip and the virtual blood vessel wall in real time, and feeds the information back to the second control device. The second control device uses the obtained distance information Combined with the operator's initial movement speed, a signal is sent to the power structure in the axial operating structure to control the operating state of the axial operating structure, which includes forward, backward, acceleration, deceleration, or stop. In the present invention, the first control device and the second control device can combine the distance between the catheter and the blood vessel wall and the input actual movement speed of the catheter to control the movement state of the axial operating structure, and the axial operating structure will generate a speed It brings tactile feedback to the operator; in the present invention, the movement state of the catheter is not limited to the operator's operating speed, and the catheter moves smoothly.

The guide structure includes a spline shaft, a first straight nut, a baffle, an encoder, a Hall sensor, a magnet, and a controller. The Hall sensor, magnet, and controller form the first control device in the guide structure. The key shaft is coaxial with the conduit. One end of the first straight nut is equipped with a baffle. One end of the spline shaft is inserted into the first straight nut from the other end of the first straight nut. One end of the conduit is connected and fixed with the baffle. An encoder is installed on the other end of the key shaft, a Hall sensor is installed on the side wall of the baffle located inside the first straight nut, and a matching Hall sensor is installed on the end face of the spline shaft located inside the first straight nut. The magnet, Hall sensor is connected through the controller to the power structure that drives the operation of the axial operating structure.

In the present invention, the spline shaft and the first straight nut are connected to form a ball guide shaft. The first straight nut is provided with a moving space for the spline shaft to move axially. During the axial movement of the spline shaft, the spline shaft moves relative to the ball guide shaft. As the first straight nut moves, the position of the magnet at the front end of the spline shaft changes, and the magnetic field intensity sensed by the Hall sensor changes accordingly. As a result, the Hall sensor outputs changing current information to the controller, which in turn drives the axial operating structure. The power structure drives the axial operation structure forward and backward, and records the movement distance information of the axial operation structure through the output pulse of the power structure of the axial operation structure, thereby obtaining the movement distance information of the catheter; in the present invention, the spline shaft and The first straight nut can only make relative movement in the radial direction. When the spline shaft rotates, the first straight nut rotates with the spline shaft. The first nut and the spline shaft do not move relative to each other. The first straight nut does not move relative to the spline shaft. Rotation of the cap causes the baffle to rotate, thereby causing the catheter to rotate, adjusting the distance between the catheter tip and the vessel wall.

The visualization device is a VR vascular system. The VR vascular system displays the movement status of the catheter in the blood vessel. The VR vascular system is equipped with a status information feedback module. The status information feedback module is connected to the power structure that drives the axial operating structure through the controller. The status The information feedback module and controller constitute the second control device in the visualization device.

When the trained doctors perform vascular interventional surgery training, they observe the VR vascular system interface while operating the catheter to obtain information on the shape of the blood vessel and the movement status of the catheter; use serial communication to transmit the catheter position information during the operation of the trained doctors to the VR vascular system to control the virtual catheter Movement, the virtual catheter at this time is in the same motion state as the catheter operated by the trained doctor. Combined with the distance information between the catheter and the blood vessel wall detected in the VR vascular system, the movement of the catheter is scaled. The movement scaling control of the catheter is based on the existing VR vascular system control is realized.

The present invention embeds the status information feedback module designed by the present invention on the basis of the developed VR vascular system for vascular interventional surgery to realize the catheter operating status detection function. When the movement information of the real catheter is transmitted into the VR vascular system, combined with the status information feedback module The output distance information is used to determine whether the operation of the trained doctor may cause the catheter tip to collide with the blood vessel wall in the VR vascular system, thereby moving and scaling the catheter to reduce the probability of collision and achieve the purpose of protecting vascular tissue; the invention has been developed The VR vascular system for vascular interventional surgery is embedded with the status information feedback module designed by the present invention, which can detect the distance between the catheter tip and the virtual blood vessel wall in real time, and feedback the information to the controller. The controller combines the obtained distance information with the operator. The initial movement speed is a dynamic structure that sends signals to control the operation of the axial operating structure. The distance between the catheter tip and the virtual blood vessel wall can be divided into three situations: "safe distance", "warning distance" and "collision" according to the value. " and "warning distance" can be set in the VR vascular system. The "collision" situation is when the collision detection algorithm in the VR vascular system detects a collision between the catheter tip and the blood vessel wall; in the present invention, the operating device and the VR blood vessel The system is connected to realize the simulation of the entire process of the doctor's vascular interventional surgery. Through motion scaling, the catheter has different movement speeds in different blood vessel diameters, optimizing the vascular intervention process, reducing potential harm to the patient, and increasing the accuracy of the intervention. Spend.

The axial operating structure is a ball screw, the guide structure is installed on the ball screw base, and the power structure driving the ball screw is a stepper motor. The axial operating structure of the present invention adopts a ball screw. The movement of the ball screw drives the conduit to move axially. The stepper motor can not only electrically drive the ball screw, but also realize the movement of the conduit with the first control device and the second control device. Intelligent control.

Stoppers are installed at both ends of the ball screw. The stopper limits the movement distance of the ball screw.

A second straight nut is installed between the spline shaft and the encoder, and the encoder is connected and fixed with the second straight nut. The second straight nut is connected to the spline shaft to form a ball guide shaft. The second straight nut and the spline shaft move relative to each other in the axial direction, but do not move relative to each other when rotating around the axis. The second straight nut does not move relative to the spline shaft. It is used to connect the spline shaft and the encoder. It is easy to use and facilitates the encoder to obtain the rotational motion information of the catheter.

A tactile feedback structure is installed in the guide structure. The catheter is equipped with a tactile feedback module in the axial direction. When the movement state of the guide structure changes, the tactile feedback structure will give the operator a tactile sensation.

The tactile feedback structure includes a spring installed between the Hall sensor and the magnet, and the spring is coaxial with the spline shaft. The invention utilizes the elastic deformation of the spring. When the motion state of the spline shaft changes, the spring can undergo significant deformation and give the operator a tactile sensation.

The operating device also includes an operating console, on which the conduit, axial operating structure, and guide structure are all installed. The operating table is the supporting device of the entire device, making it easier for the operator to operate.

Compared with the prior art, the present invention has the following advantages and beneficial effects:

1. The vascular interventional surgery training system based on motion scaling of the present invention changes the control placement and control method of the catheter forward and backward in the axial direction, and adds a first control device and a second control device, and a first control device and a second control device. The device cooperates to control the advancement, retreat and speed of the catheter movement. The movement of the catheter is not limited to the operator's operating speed;

2. The vascular interventional surgery training system based on motion scaling of the present invention can provide the operator with obvious tactile perception.

Description of the drawings

The drawings described here are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation to the embodiments of the present invention. In the attached picture:

Figure 1 is a schematic structural diagram of the present invention;

Figure 2 is a partial structural diagram of the present invention.

Marks and corresponding parts names in the attached drawings:

1-Conduit, 2-Spline shaft, 3-First straight nut, 4-Baffle, 5-Encoder, 6-Ball screw, 7-Limiter, 8-Second straight nut, 9- Operating table, 10-spring, 11-Hall sensor, 12-magnet.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below in conjunction with the examples and drawings. The schematic embodiments of the present invention and their descriptions are only used to explain the present invention and do not as a limitation of the invention.

Example 1

As shown in Figure 1, the vascular interventional surgery training system based on motion scaling of the present invention includes an operating device and a visualization device. The operating device includes a catheter 1, an axial operating structure that drives the axial movement of the catheter 1, and a rotational movement that drives the catheter 1. The guide structure is provided with a first control device for controlling the operation of the axial operating structure, and the visualization device is provided with a second control device for controlling the operation of the axial operating structure. The operating device also includes an operating console 9, on which the conduit 1, the axial operating structure, and the guide structure are all installed.

The invention utilizes the principle of catheter motion scaling to simulate the operation of vascular interventional surgery by surgeons, designs a reasonable operation plan of the catheter, and provides effective tactile feedback in the horizontal direction; it solves the problem that the catheter in traditional vascular interventional equipment is limited by the operator's operation. disadvantages of speed and increased safety during catheter intervention. The doctor inserts the catheter into the blood vessel, mainly by operating the catheter forward and backward and clockwise or counterclockwise rotation; in the present invention, the axial forward and backward movement of the catheter is realized by the axial operating structure, and the rotational movement of the catheter is realized by the guide structure; existing The forward and backward movement of the catheter in the vascular interventional equipment is manually controlled, and the moving speed of the catheter is manually limited; the present invention changes the control placement and control method of the forward and backward movement of the catheter in the axial direction. In the case of manual movement of the catheter, the present invention increases A first control device and a second control device are provided. The first control device and the second control device cooperate to control the forward and backward movement of the catheter and the speed of the catheter movement. The movement of the catheter is not limited to the operator's operating speed.

Example 2

Based on Embodiment 1, as shown in Figures 1 and 2, the guide structure includes a spline shaft 2, a first straight nut 3, a baffle 4, an encoder 5, a Hall sensor 11, a magnet 12, and a controller. The Hall sensor 11, the magnet 12, and the controller form the first control device in the guide structure. The spline shaft 2 is coaxial with the conduit 1. One end of the first straight nut 3 is equipped with a baffle 4, and one end of the spline shaft 2 Insert the first straight nut 3 from the other end of the first straight nut 3. One end of the conduit 1 is connected and fixed with the baffle 4. The encoder 5 is installed on the other end of the spline shaft 2. The baffle 4 is located on the first straight nut 3. A Hall sensor 11 is installed on the side wall inside the nut 3. A magnet 12 matching the Hall sensor 11 is installed on one end of the spline shaft 2 inside the first straight nut 3. The Hall sensor 11 passes through the controller. Connected to the power structure driving the operation of the axial operating structure. A second straight nut 8 is installed between the spline shaft 2 and the encoder 5, and the encoder 5 and the second straight nut 8 are connected and fixed. The axial operating structure is a ball screw 6, the guide structure is installed on the base of the ball screw 6, and the power structure that drives the ball screw 6 is a stepper motor. Limiters 7 are installed at both ends of the ball screw 6 .

When the spline shaft moves axially relative to the first straight nut, the position of the magnet at the front end changes, and the magnetic field intensity sensed by the Hall sensor changes accordingly. As a result, the Hall sensor outputs changing current information to the controller, and then The stepper motor is driven to drive the forward and backward motion of the ball screw, and the movement distance information of the screw is recorded through the output pulse of the stepper motor, thereby obtaining the movement distance information of the conduit. In addition, the rotational movement information of the conduit is obtained through an encoder directly connected to the ball guide shaft composed of the spline shaft, the first straight nut, and the second straight nut; the operator holds the spline shaft to perform rotational movement, and the spline shaft There is no relative movement with the straight nut in the direction of rotation, and the encoder is fixedly connected to the second straight nut to obtain accurate rotation angle information of the catheter.

Example 3

Based on Embodiment 1, the visualization device is a VR vascular system. The VR vascular system displays the movement status of the catheter in the blood vessel. The VR vascular system is provided with a status information feedback module. The status information feedback module operates through the controller and the drive axial operating structure. The power structure is connected, the status information feedback module and the controller form the second control device in the visualization device. The axial operating structure is a ball screw 6, the guide structure is installed on the base of the ball screw 6, and the power structure that drives the ball screw 6 is a stepper motor. Limiters 7 are installed at both ends of the ball screw 6 .

By transmitting the forward and backward movement information of the catheter and the clockwise or counterclockwise rotation information of the catheter into the VR vascular system, the accurate movement status of the catheter in the blood vessel can be represented in VR; the movement distance of the catheter in the VR vascular system is consistent with the hardware device The motion information of the ball screw is consistent. In order to optimize the motion of the catheter in the VR vascular system, this system adds motion scaling control. Based on the developed VR vascular system for vascular interventional surgery, it is implemented by embedding the status information feedback module we designed. The catheter operating status detection function detects the distance between the catheter tip and the virtual blood vessel wall in real time. This distance can be divided into three situations: "safety distance", "warning distance" and "collision" according to the value, and the information is fed back to the controller. The controller sends a signal to control the motor to drive the screw based on the obtained distance information combined with the operator's initial movement speed. Taking the forward movement of the operating catheter as an example, when the detected distance information is the "warning distance" and the initial speed given by the operator to the screw is higher than the set threshold, the screw speed is multiplied by a proportional coefficient less than 1, so that The catheter runs at a speed less than the speed given by the operator, and at the same time provides the operator with a sense of touch to serve as a reminder. There is a hook in front of the catheter, which changes its direction by rotating it, and then through operations such as forward and backward movement of the catheter, the steering is finally achieved. Adjust the distance between the catheter tip and the blood vessel; when the detected distance information is "safe distance", the catheter runs at the speed given by the operator; when the detected distance information is "collision", multiply the screw speed by Use a smaller proportional coefficient to decelerate the catheter or directly force the hardware device to stop the axial movement of the catheter according to the actual situation. By rotating the catheter and other operations, after the distance information is out of the "collision" area, the catheter must move according to the scaling strategy. This enables the movement scaling of the catheter in VR and the tactile reminder function in the horizontal direction.

The limits of the safety distance and warning distance can be set by yourself in the VR vascular system. The "collision" situation is when the collision detection algorithm in the VR vascular system detects a collision between the catheter tip and the blood vessel wall. For each distance, ensure that no collision occurs. Set a safe displacement threshold under the premise. When the movement information of the real catheter is transmitted to the VR vascular system, the movement of the catheter is scaled by comparing whether the displacement of the real catheter at the currently detected distance is within the safe displacement threshold. The specific scaling strategies are as follows:

Among them, χ _m and χ represent the displacement before and after scaling of the catheter motion, respectively, and μ is the scaling factor.

This system can compare the distance between the catheter tip and the blood vessel wall for different catheter motion states, and perform reasonable motion scaling of the catheter. For example, when the blood vessel wall and the tip of the catheter are at a warning distance, but the operating displacement of the trained doctor is greater than the maximum safety threshold at the warning distance, the displacement of the virtual catheter will be reduced proportionally, and the reduced displacement will be returned to the lower machine. , and converted into a speed value. At this time, the running speed of the stepper motor is reduced, thereby reducing the movement speed of the real catheter. In a short period of time, the movement speed of the real catheter is lower than the speed that the trained doctor expected to push the catheter. The screw gives a "touch force" opposite to the current operating direction of the trained doctor, realizing the force/tactile interaction of the trained doctor's hand. Through tactile reminders and visual information fed back from the VR vascular system interface, trained doctors can quickly realize that their operations are wrong and correct their operations, thereby reducing the collision between the catheter tip and the blood vessel wall and protecting the vascular tissue.

Example 4

Based on the above embodiment, as shown in Figure 2, a tactile feedback structure is installed in the guide structure. The tactile feedback structure includes a spring 10 installed between the Hall sensor 11 and the magnet 12. The spring 10 is coaxial with the spline shaft 2. . The actual movement of the catheter deviates from the speed at which the operator expects the movement of the catheter. This deviation causes the spring to compress, giving the operator a force opposite to the operating direction, which is the touch force that the operator can feel.

Example 5

Based on Embodiments 1-4, the operating steps of the vascular interventional surgery training system based on motion scaling of the present invention are specifically:

S1. Construct a vascular intervention model in the VR vascular system, and connect the entire hardware operating device with the VR vascular system to simulate the entire process of the doctor's vascular interventional surgery;

S2. Move the spline shaft in the axial direction, the position of the magnet at the front end of the spline shaft changes, and the magnetic field intensity sensed by the Hall sensor changes accordingly. As a result, the Hall sensor outputs changing current information to the controller, and then drives the stepper. Enter the motor and give the ball screw an initial movement speed. The catheter that moves the ball screw forward moves forward in the blood vessel;

S3. The VR vascular system detects the distance between the catheter tip and the virtual blood vessel wall in real time. This distance can be divided into three situations: "safe distance", "warning distance" and "collision" according to the value. After the information is fed back to the controller, the control Based on the obtained distance information combined with the operator's initial movement speed, the device sends a signal to control the stepper motor to drive the ball screw; for example: when the catheter needs to be turned, the distance between the catheter and the blood vessel wall will become smaller, and in the "warning distance" Or under a "collision" alarm, the direction of the catheter tip hook is changed by rotating the spline shaft, and then the first control device and the second control device simultaneously control the catheter to move forward and backward, and finally realize the catheter steering, adjust the catheter tip and The distance between blood vessels; the VR blood vessel system gives a control signal to the ball screw through the second control device, and the wire structure also gives a control signal to the ball screw through the first control device, and both give control signals to the ball screw at the same time. There will be a speed difference between them, and the operator will get tactile feedback through the speed difference;

S4. When the ball screw advances or retreats to the position of the limiter, the ball screw stops moving. At this time, the VR vascular system suspends operation until the ball screw is controlled to return to the origin, and the VR vascular system continues to run.

The present invention combines VR distance measurement information, utilizes the principle of catheter motion scaling, optimizes the motion of the catheter, and provides a tactile reminder function in the horizontal direction of the hardware device.

The above-described specific embodiments further describe the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above-mentioned are only specific embodiments of the present invention and are not intended to limit the scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims (6)

1. The vascular intervention operation training system based on motion scaling comprises an operation device and a visualization device, wherein the operation device comprises a catheter (1), an axial operation structure for driving the catheter (1) to axially move and a guide structure for driving the catheter (1) to rotationally move, and is characterized in that a first control device for controlling the operation of the axial operation structure is arranged in the guide structure, and a second control device for controlling the operation of the axial operation structure is arranged in the visualization device;

the guide structure comprises a spline shaft (2), a first straight screw cap (3), a baffle plate (4), an encoder (5), a Hall sensor (11), a magnet (12) and a controller, wherein the Hall sensor (11), the magnet (12) and the controller form a first control device in the guide structure, the spline shaft (2) is coaxial with a guide pipe (1), the baffle plate (4) is arranged at one end of the first straight screw cap (3), one end of the spline shaft (2) is inserted into the first straight screw cap (3) from the other end of the first straight screw cap (3), one end of the guide pipe (1) is fixedly connected with the baffle plate (4), the encoder (5) is arranged at the other end of the spline shaft (2), the Hall sensor (11) is arranged on the side wall of the baffle plate (4) positioned in the first straight screw cap (3), the magnet (12) matched with the Hall sensor (11) is arranged on the end face of one end of the spline shaft (2), and the Hall sensor (11) is connected with a power structure for driving the axial operation structure through the controller;

a tactile feedback structure is arranged in the guide structure and comprises a spring (10) arranged between the Hall sensor (11) and the magnet (12), and the spring (10) is coaxial with the spline shaft (2);

the visual device gives a control signal to the axial operating mechanism through the second control device, the guide structure also gives a control signal to the axial operating mechanism through the first control device, the first control device and the second control device can generate speed difference between the control signals to the axial operating mechanism at the same time, and an operator obtains tactile feedback through the speed difference.

2. The vascular interventional operation training system based on motion scaling according to claim 1, wherein the visualization device is a VR vascular system, the VR vascular system displays the motion state of the catheter in the blood vessel, a state information feedback module is arranged in the VR vascular system, the state information feedback module is connected with a power structure for driving the axial operation structure to operate through a controller, and the state information feedback module and the controller form a second control device in the visualization device.

3. Vascular intervention training system based on motion scaling according to claim 1 or 2, wherein the axial operation structure is a ball screw (6), the guiding structure is mounted on the base of the ball screw (6), and the power structure driving the ball screw (6) to run is a stepper motor.

4. A vascular interventional procedure training system based on motion scaling according to claim 3, characterized in that the ball screw (6) is fitted with stoppers (7) at both ends.

5. Vascular intervention training system based on motion scaling according to claim 1, characterized in that a second straight screw cap (8) is mounted between the spline shaft (2) and the encoder (5), the encoder (5) being fixedly connected with the second straight screw cap (8).

6. Vascular intervention training system based on motion scaling according to claim 1, characterized in that the operating means further comprise an operating table (9), the catheter (1), the axial operating structure, the guiding structure being mounted on the operating table (9).