Sensor-enhanced microcatheter positioning system

Abstract

The invention provides a sensor-enhanced microcatheter positioning system which aims to reduce radiation exposure of a patient and accurately position the tip of a microcatheter in real time. The system comprises a micro catheter, a sensor enhancing guide wire, external measuring equipment, a microcontroller and data processing software. The microcatheter is designed for interventional surgery and used in cooperation with a sensor enhanced guide wire, and an electromagnetic sensor is arranged in the sensor enhanced guide wire to track the position of the sensor enhanced guide wire in a blood vessel. An external measurement device measures linear displacement of the catheter relative to the guidewire based on the rotary encoder. The microcontroller reads measurement data and converts the measurement data into digital information, and the data processing software is realized by adopting MATLAB, converts the data into three-dimensional position information, and displays the three-dimensional position information on a graphical user interface for a doctor to check. The system predicts the guide wire path through an energy minimization algorithm, provides immediate feedback and assists surgical navigation.

Description

Technical Field

[0001] The present application belongs to the field of medical devices, and specifically relates to a sensor-enhanced micro-catheter positioning system. Background Art

[0002] Microcatheters are widely used in cardiac surgery, especially in interventional cardiac surgery. Due to their small diameter and flexible operation, microcatheters can pass through narrow or curved blood vessels and reach the site where the surgery is required. Microcatheters play a very important role in the treatment of coronary artery stenosis or obstruction, heart valve replacement, arrhythmia and other surgeries. With the continuous innovation of medical technology, the existing microcatheters have some limitations in positioning technology during use. Most microcatheter position tracking technologies rely more on X-ray machines for real-time tracking, which will cause radiation to patients and medical personnel, and pose a greater health risk in the long run. In addition, they can only provide two-dimensional position information and cannot accurately understand the three-dimensional position of the microcatheter in the body.

[0003] In view of this, the present application has developed a sensor-enhanced microcatheter positioning system that can accurately locate the catheter tip in real time without increasing the patient's radiation exposure. The system includes an external measurement device used in conjunction with the microcatheter, which uses a sensor-enhanced guidewire to track the relative movement of the catheter and predicts the position of the catheter in the blood vessel through a software algorithm. Summary of the invention

[0004] The present application provides a sensor-enhanced microcatheter positioning system, which aims to reduce the patient's radiation exposure while accurately positioning the tip of the microcatheter in real time. A sensor-enhanced microcatheter positioning system comprises:

[0005] The microcatheter includes, from the proximal end to the distal end, a catheter connector, a catheter sheath, a catheter holder, a side wall Luer connector, an axis marker, and a proximal marker;

[0006] Sensor-enhanced guidewires, which have a built-in electromagnetic sensor at the distal end to track the exact position of the guidewire within the patient's body in real time;

[0007] An external measurement device, based on a rotary encoder design, is used to measure the linear displacement of the microcatheter relative to the sensor-enhanced guidewire;

[0008] A microcontroller that reads the signals from external measuring devices and converts them into digital information;

[0009] Data processing software, implemented in MATLAB, was used to process the microcontroller data and display a three-dimensional representation of the microcatheter position.

[0010] According to one embodiment of the present application, at least two development marks are provided on the shaft mark, and the interval between the development marks is not less than 10 cm.

[0011] According to one embodiment of the present application, the external measuring device is a clamp structure for use in conjunction with a microcatheter and a sensor-enhanced guidewire.

[0012] According to one embodiment of the present application, the electromagnetic sensor of the sensor-enhanced guidewire can be integrated with the hospital's existing navigation system to provide precise position information of the microcatheter.

[0013] According to one embodiment of the present application, a method for simulating a guidewire path using a sensor-enhanced microcatheter positioning system is proposed, comprising the following steps:

[0014] a. Use medical imaging technology to obtain the three-dimensional structure of blood vessels;

[0015] b. Reconstruct the centerline and lumen of the blood vessel;

[0016] c. Apply graph theory models and energy minimization algorithms to determine the optimal path of the sensor-enhanced guidewire through an iterative process;

[0017] d. Searching for the guidewire path in the weighted graph using the shortest path algorithm;

[0018] e. The graphical user interface is updated in real time to display the predicted path of the guidewire.

[0019] According to one embodiment of the present application, parameters such as stiffness, number of vertices and number of levels of the guidewire are adjusted during the simulation process to optimize the accuracy of the guidewire path simulation.

[0020] According to an embodiment of the present application, the mean square error RMS between the simulated position and the actual position is calculated to quantify the simulation accuracy, and the calculation formula is as follows:

[0021]

[0022] Where N is the total number of values ​​in the data set, x i is the actual value of the ith value in the data set. i is the ith simulated value in the data set.

[0023] According to one implementation of the present application, the RMS is found to be between 0.9 mm and 1.3 mm, verifying the accuracy of the simulation.

[0024] The beneficial effects of the present application are as follows: the sensor-enhanced microcatheter positioning system provided by the present application reduces the risk of radiation exposure to patients and medical staff by reducing the reliance on real-time imaging technology, and the real-time feedback function of the system improves the accuracy and safety of surgery, especially in complex vascular structures. In addition, the high-resolution position feedback and fast computing power of the external measuring device make the simulation of the guidewire path more accurate and rapid, thereby shortening the operation time. The design of the system also takes into account the ease of operation. The coordinated use of microcatheters and sensor-enhanced guidewires simplifies the surgical process. Finally, through an algorithm that combines graph theory and physical models, the system can predict the optimal path of the guidewire in the blood vessel, providing doctors with a powerful tool to better plan operations and make decisions. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work, among which:

[0026] Figure 1 is a schematic diagram of a sensor-enhanced microcatheter system of the present application;

[0027] Figure 2 It is a schematic diagram of the structure of a microcatheter of the present application;

[0028] Figure 3 This is a schematic diagram of the cooperation between a sensor-enhanced guidewire and a microcatheter of the present application;

[0029] in:

[0030] 100. Microcatheter; 101. Catheter connector; 102. Catheter sheath; 103. Catheter holder; 104. Side wall Luer connector; 105. Axis marker; 106. Proximal marker; 200. Sensor-enhanced guidewire; 300. External measuring device; 400. Microcontroller; 500. Data processing software. DETAILED DESCRIPTION

[0031] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. It is to be understood that the specific embodiments described herein are only used to explain the present application, rather than to limit the present application. It should also be noted that, for ease of description, only some structures related to the present application are shown in the accompanying drawings, rather than all structures. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0032] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0033] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0034] The present application provides a sensor-enhanced microcatheter positioning system designed to accurately locate the catheter tip in real time without increasing the patient's radiation exposure. The system includes an external measurement device used in conjunction with the microcatheter, which uses a sensor-enhanced guidewire to track the relative movement of the catheter and predicts the position of the catheter in the blood vessel through a software algorithm.

[0035] The present application provides a sensor-enhanced microcatheter positioning system, such as Figure 1 As shown, the system includes: a microcatheter 100 , a sensor-enhanced guidewire 200 , an external measurement device 300 , a microcontroller 400 , and data processing software 500 .

[0036] See also Figure 2The microcatheter 100 is a slender tubular device used in interventional surgery so that doctors can accurately deliver treatment tools or drugs to specific parts of the patient's body. The structure of the microcatheter 100 includes, from the proximal end to the distal end, a catheter connector 101, a catheter sheath 102, a catheter holder 103, a sidewall Luer connector 104, an axis marker 105, and a proximal marker 106. The catheter connector 101 is made of metal to ensure compatibility with other devices in specific operations and the firmness of the connection. The catheter sheath 102 is made of soft polymer material to protect the catheter body and provide good tactile feedback to the doctor during the insertion process. The catheter holder 103 is designed to fix the position of the microcatheter during surgery to prevent it from shifting in the blood vessel. The sidewall Luer connector 104 is a quick connection device that allows medical professionals to quickly and easily connect or disconnect syringes, infusion tubes and other medical devices. The sidewall Luer connector 104 is also provided with an interface with a Luer locking mechanism to ensure the sealing and stability of the connection. The axis mark 105 and the proximal mark 106 provide the doctor with a visual reference of the microcatheter 100, which is essential for accurate navigation. A development mark is provided on the axis mark 105, and the interval between the development marks is not less than 10 cm. The development mark is made of high-contrast material to ensure sufficient visibility in imaging equipment such as X-ray imaging, and can be clearly identified even under low-dose imaging conditions.

[0037] The introduction of the sensor-enhanced guidewire 200 solves the technical problem of the difficulty in accurately tracking the position of the guidewire in traditional interventional surgery. Figure 3 As shown, the sensor-enhanced guidewire 200 is used in conjunction with the microcatheter 100, and the electromagnetic sensor 210 built into the distal end thereof can be integrated with the hospital's existing navigation system to track the exact position of the sensor-enhanced guidewire 200 in the patient's body in real time, thereby providing accurate position information of the tip of the microcatheter 100. This real-time tracking capability greatly improves the accuracy and safety of the surgery, especially in complex vascular structures that require precise positioning.

[0038] The data of the sensor 210 is read by the external measuring device 300. The external measuring device 300 is designed based on a rotary encoder and can provide high-resolution position feedback. The external measuring device 300 can be designed as a clamp or roller structure and used in conjunction with the microcatheter 100 or the sensor-enhanced guidewire 200. The linear displacement of the microcatheter 100 relative to the sensor-enhanced guidewire 200 is measured by the movement of the rotary encoder, and these mechanical displacements are converted into electrical signals.

[0039] The microcontroller 400 serves as the electronic control unit of the system, and is used to read the signal of the external measuring device 300 and convert it into digital information for further processing. The data processing software 500, implemented using MATLAB software, is not only used to process the data of the microcontroller 400, but is also responsible for further generating a user interface to intuitively display the information. The MATLAB script is capable of receiving the data of the microcontroller 400 and converting it into a three-dimensional representation of the position of the microcatheter 100, thereby displaying the relative position of the microcatheter 100 and the sensor-enhanced guidewire 200 on the user interface, as well as the predicted path of the microcatheter 100 in the blood vessel, and this information is finally displayed on the user interface for the doctor to view.

[0040] In order to realize this technical solution, a series of development and testing work is required. First, the design of the microcatheter 100 and the sensor-enhanced guidewire 200 must comply with the biocompatibility and sterility requirements of medical devices to ensure safety and effectiveness during surgery. Secondly, the design of the external measuring device 300 needs to take into account the actual operating conditions during the operation, including the stability of the clamp or roller structure and the ability to accurately track the guidewire. The programming of the microcontroller 400 needs to ensure that the signals from the external measuring device 300 can be accurately read and processed. The development of the data processing software 500 needs to combine graph theory and physical models to achieve energy minimization simulation of the guidewire path and provide an intuitive and easy-to-use user interface.

[0041] By testing the use of the microcatheter 100 and the sensor-enhanced guidewire 200 in a simulated vascular environment, the precision of the external measurement device 300 and the simulation accuracy of the data processing software 500 can be evaluated. The accuracy of the guidewire path simulation can be optimized by adjusting the algorithm parameters, such as the stiffness of the guidewire, the number of vertices on each level, the number of levels used, etc. In addition, the accuracy of the algorithm can be evaluated by comparing with the guidewire position in the actual vascular model and determining the mean square error RMS between the simulated position and the actual position.

[0042] Further, the present application provides a method for accurately tracking and simulating the path of a sensor-enhanced guidewire within a blood vessel, such as Figure 3 As shown, an energy minimization algorithm is used to predict the path of the sensor-enhanced guidewire 200 in the blood vessel by analyzing the motion data of the sensor-enhanced guidewire 200, without relying on continuous real-time imaging technology. This method not only reduces the reliance on continuous real-time radiation imaging, but also can quickly provide updates on the guidewire path by processing the position data of the sensor-enhanced guidewire in real time, providing instant feedback for surgery.

[0043] First, medical imaging techniques (such as CT, MRI or angiography) are used to obtain the detailed three-dimensional structure of the blood vessel to provide the necessary anatomical information for the subsequent guidewire path simulation. Then, the centerline and cavity of the blood vessel are reconstructed from the acquired three-dimensional image to determine the geometric center and cavity boundary of the blood vessel. The blood vessel is divided into multiple segments, each of which represents a level in the graph theory model. Cross-sectional planes are determined on the centerline of each blood vessel segment. These planes are perpendicular to the local centerline of the blood vessel, and the blood vessel radius is used to determine the position of the blood vessel cavity. A series of spatial points are defined on each cross-sectional plane. These points represent the locations where the sensor-enhanced guidewire 200 may pass through, forming nodes in the graph theory model.

[0044] Secondly, for each possible position of the sensor-enhanced guidewire 200 in the blood vessel, the corresponding energy is calculated, and the local bending energy of the sensor-enhanced guidewire 200 is related to the local bending angle using a preset energy function model based on the physical properties and geometric constraints of the microcatheter 100. The local bending energy of the sensor-enhanced guidewire 200 is given by the following formula:

[0045]

[0046] Wherein, E is Young's modulus, I is the cross-sectional inertia moment of the guidewire, and θ is the bending angle of the guidewire between two adjacent points. The total energy of the sensor-enhanced guidewire 200 is minimized through an iterative process to determine the optimal path of the guidewire. This process involves searching for the minimum energy path, i.e., the equilibrium state of the sensor-enhanced guidewire 200, in a graph theory model.

[0047] The path of the sensor-enhanced guidewire 200 is searched in the weighted graph using the shortest path algorithm. This path represents the energy-minimized position of the sensor-enhanced guidewire 200 within the blood vessel. The algorithm can quickly calculate the guidewire position and provide real-time feedback to the physician. At the same time, the graphical user interface is updated to display the real-time position and predicted path of the guidewire to help the physician navigate the surgery.

[0048] In addition, the accuracy of the guidewire position under different simulation conditions was evaluated by comparing the position of the sensor-enhanced guidewire 200 in the actual blood vessel model. The mean square error RMS between the simulated position and the actual position is used to quantify the difference between the simulated guidewire position and the actual guidewire position, and its calculation formula is shown as follows:

[0049]

[0050] Where N is the total number of values ​​in the data set, x i is the actual value of the ith value in the data set. iis the ith simulation value in the data set. The RMS is between 0.9 mm and 1.3 mm, which verifies the accuracy of the simulation. For simulations with different vascular curvatures or different guidewire material properties, such as in high-curvature vessels, the minimum energy position of the guidewire is more predictable, which provides a theoretical basis for using this technology in complex vascular structures.

[0051] The technology of this application can complete the simulation of guidewire position in a short time, which is crucial for real-time surgical navigation and decision support. By reducing the reliance on radiation imaging, this technology helps reduce the risk of radiation exposure for patients and medical staff. In addition, the fast computing power of this method gives it significant advantages in clinical applications, especially in intravascular interventional surgeries that require rapid decision-making and operations. By adjusting the parameters in the algorithm, guidewires with different material properties can be simulated, providing doctors with guidewire position simulations in different situations, increasing the flexibility and adaptability of the technology.

[0052] The above description is only an implementation method of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A sensor-enhanced microcatheter positioning system, characterized in that: The microcatheter includes, from the proximal end to the distal end, a catheter connector, a catheter sheath, a catheter holder, a side wall Luer connector, an axis marker, and a proximal marker; Sensor-enhanced guidewires, which have a built-in electromagnetic sensor at the distal end to track the exact position of the guidewire within the patient's body in real time; An external measurement device, based on a rotary encoder design, is used to measure the linear displacement of the microcatheter relative to the sensor-enhanced guidewire; A microcontroller that reads the signals from external measuring devices and converts them into digital information; Data processing software, implemented in MATLAB, was used to process the microcontroller data and display a three-dimensional representation of the microcatheter position.

2. The sensor-enhanced microcatheter positioning system according to claim 1, characterized in that: At least two developing marks are arranged on the axis mark, and the interval between the developing marks is not less than 10 cm.

3. The sensor-enhanced microcatheter positioning system according to claim 1, characterized in that: The external measuring device is a clamp structure used in conjunction with a microcatheter and a sensor-enhanced guidewire.

4. The sensor-enhanced microcatheter positioning system according to claim 1, characterized in that: The electromagnetic sensor of the sensor-enhanced guidewire can be integrated with a hospital's existing navigation system to provide precise position information of the microcatheter.

5. A method for simulating a guidewire path using the sensor-enhanced microcatheter positioning system according to any one of claims 1 to 4, characterized in that: Includes steps: a. Use medical imaging technology to obtain the three-dimensional structure of blood vessels; b. Reconstruct the centerline and lumen of the blood vessel; c. Apply graph theory models and energy minimization algorithms to determine the optimal path of the sensor-enhanced guidewire through an iterative process; d. Searching for the guidewire path in the weighted graph using the shortest path algorithm; e. The graphical user interface is updated in real time to display the predicted path of the guidewire.

6. The method for simulating a guidewire path according to claim 5, characterized in that: During the simulation, the stiffness, number of vertices, and number of levels of the guidewire were adjusted to optimize the accuracy of the guidewire path simulation.

7. The method for simulating a guidewire path according to claim 5, characterized in that: The mean square error (RMS) between the simulated position and the actual position is calculated to quantify the simulation accuracy. The calculation formula is as follows: Where N is the total number of values ​​in the data set, x i is the actual value of the ith value in the data set; y i is the ith simulated value in the data set.

8. The method for simulating a guidewire path according to claim 7, characterized in that: The RMS error is between 0.9 mm and 1.3 mm.

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