FBG-based vascular stenosis sensing system

Abstract

The present invention provides a vascular stenosis sensing system based on FBG, comprising a flow pump simulating blood flow, a multi-point bendable FBG sensor module, a curved vascular stenosis model, a waste liquid recovery system, a signal detection system and an analysis system, wherein the flow pump, the curved vascular stenosis model and the waste liquid recovery system are connected in sequence; the sensor FBG extends into the curved vascular stenosis model along the bending direction of the blood vessel, and a plurality of evenly distributed FBGs are arranged in different blood vessel segments; the signal detection system receives the wavelength reflected from the FBG and generates a corresponding time-varying output signal. The analysis system obtains the flow rate and flow velocity of the simulated blood flow, calculates the wavelength change at each position along the FBG, and converts it into a strain signal output, thereby determining the position and size of the vascular stenosis and distortion area. The present invention is advantageous for rapid scanning of arterial blood vessels to diagnose stenosis areas without relying on the radiation examination of iodinated contrast agents, and can obtain efficient examination results of vascular stenosis diseases.

Description

Technical Field

[0001] The present invention relates to the field of medical detection, and in particular to a FBG-based vascular stenosis sensing system. Background Art

[0002] The mortality rate of vascular diseases ranks first in the world, and 2 out of every 5 cases in the world die from cardiovascular diseases. According to incomplete statistics, the number of cardiovascular disease patients in China is 330 million. Traditional vascular aberration detection, firstly, iodinated contrast agents are harmful to the human body and doctors, and require a very complicated and time-consuming invasive process; secondly, it is difficult to work with interventional robots. The radiation-free, non-toxic, and rapid detection of vascular aberrations is a technology that the world is eagerly waiting for, and low damage, precise positioning and perception of vascular lesions are the current difficulties of interventional medical robots.

[0003] FBG has good magnetic compatibility, small size, and flexible changeability. The present invention combines the advantages of magnetic resonance imaging (MRI) and FBG sensing, with the goal of "non-radiation, non-toxic, and accurate detection of vascular malformation, stenosis, and distortion". The magnetic compatibility, flexibility, and small size of fiber Bragg grating sensors are used to enable medical intervention robots to accurately locate in closed vascular cavities. The scientific problem proposed is characterized by "demand-driven, bottleneck-breaking".

[0004] In recent years, well-known foreign robotics research institutions and leading enterprises are accelerating the layout of high-end medical equipment and sensing technology. The FBG shape fiber sensing detection system developed by TSSC in the United States can realize spatial three-dimensional shape perception, and the linear continuous shape sensor developed has been commercialized in equipment such as interventional surgical robot navigation. The magnetic resonance soft robot developed by Medtronic in the United States has begun to be used in clinical practice; the pneumatically driven magnetic resonance compatible prostate interventional surgical robot system developed by Johns Hopkins University in the United States has obtained FDA certification; the University of Hong Kong has also developed a hydraulically driven cardiovascular interventional surgical robot. In my country, the research and development of related technical systems started late, lacking key equipment research and development and core technologies. The multi-core FBG sensor developed by Shanghai Jiaotong University is in the laboratory test stage, and cardiac interventional surgical robots have also made progress.

[0005] The present invention combines the characteristics of small scale, flexible deformation, and magnetic compatibility of optical fiber FBG sensing, and proposes a real-time detection system for FBG sensing of vascular stenosis, breaking through the radiation problem of iodinated contrast agents in traditional vascular stenosis and distortion detection; exploring the correlation mechanism between FBG sensing reflection wavelength and changes in cardiac stenosis blood flow signs; inventing a non-toxic, radiation-free vascular detection system, which is expected to be applied to vascular intervention robots. In the field of technical application, it will promote the realization of the "integrated diagnosis and treatment system" of medical robot equipment. It has important theoretical significance and scientific value in breaking the technical monopoly of foreign high-end medical equipment and innovating my country's core key sensing technologies. Summary of the invention

[0006] In view of the defects in the prior art, the object of the present invention is to provide a vascular stenosis sensing system based on FBG.

[0007] According to the present invention, a FBG-based vascular stenosis sensing system includes a flow pump simulating blood flow, a multi-point bendable FBG sensor module, a curved vascular stenosis model, a waste liquid recovery system, and an FBG signal detection and analysis system, wherein:

[0008] A flow pump simulating blood flow, a curved blood vessel stenosis model, and a waste fluid recovery system are connected in sequence;

[0009] The FBG sensor module is inserted into the vascular distortion model;

[0010] The signal detection system detects the flow rate and strain of the simulated blood flow;

[0011] The signal analysis system receives data from the FBG sensor module and the signal detection system, and the analysis system analyzes the relationship between the stress-strain signal of the sensor FBG and the vascular strain caused by vascular distortion and stenosis.

[0012] Preferably, it also includes color ultrasound, which verifies the detection result of the FBG sensor module.

[0013] Preferably, the multi-point bendable FBG sensor module comprises a spatial optical fiber morphology FBG multi-point grating array.

[0014] Preferably, the multi-point Bragg grating is provided in plurality and can enter a blood vessel with a diameter of 4 mm-8 mm, and the bending degree of the FBG sensor module is ±120°.

[0015] Preferably, the curved blood vessel stenosis model comprises a mounting box and a plurality of curved blood flow channels, wherein: a plurality of mounting holes are provided on two opposite sides of the mounting box, and the plurality of blood flow channels are mounted in the mounting box through the mounting holes;

[0016] A narrow area is cast in the middle of some blood flow channels, and the narrow areas cast in the middle of different blood flow channels are different.

[0017] Preferably, a three-way joint is provided on the side of the installation box, and the FBG sensor module is arranged in one of the joints.

[0018] Preferably, the flow pump simulating blood flow and the curved blood vessel stenosis model, and the curved blood vessel stenosis model and the waste liquid recovery system are connected through acrylic tubes.

[0019] Preferably, the signal detection system comprises a liquid pressure sensor and a liquid flow sensor, wherein the liquid pressure sensor detects the pressure of the simulated blood flow in the acrylic tube; and the liquid flow sensor detects the flow rate of the simulated blood flow in the acrylic tube.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The present invention has ingenious structure, convenient operation and low cost.

[0022] 2. The multi-point Bragg grating bendable FBG sensor of the present invention has the characteristics of good magnetic compatibility, small size, and flexible changeability, so that the medical intervention robot can accurately position itself in a closed blood vessel cavity.

[0023] 3. The spatial curved vascular stenosis model of the present invention sets blood vessels with different diameters and stenosis areas, effectively simulating the stenosis and distortion of human blood vessels.

[0024] 4. The FBG-based vascular stenosis sensing system of the present invention breaks through the radiation problem of relying on iodinated contrast agents in traditional vascular stenosis and distortion CT detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0026] Figure 1 Schematic diagram of the FBG-based vascular stenosis sensing system.

[0027] Figure 2 and 3 Schematic diagram of the curved blood vessel stenosis model of the FBG-based blood vessel stenosis sensing system.

[0028] Figure 4 Schematic diagram of a multi-point curved FBG string sensor for the FBG-based vascular stenosis sensing system. DETAILED DESCRIPTION

[0029] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0030] like Figures 1 to 4As shown, a vascular stenosis sensing system based on FBG according to the present invention includes a flow pump (PP) simulating blood flow, a multi-point bendable sensor FBG, a curved vascular stenosis model (XM), a waste liquid recovery system (FH), and an FBG signal detection and analysis system (DA). The flow pump simulating blood flow, the curved vascular stenosis model, and the waste liquid recovery system are connected in sequence; the FBG sensor module is arranged in the curved vascular stenosis model; the signal detection system detects the flow and pressure of the simulated blood flow; the signal analysis system receives data from the FBG sensor module and the signal detection system, and analyzes the relationship between the stress strain signal of the FBG sensor module and the changes in vascular pressure, flow, and flow velocity caused by vascular distortion and stenosis. The multi-point bendable FB optical fiber extends into the curved vascular stenosis model (XM) along the bending direction of the blood vessel, and 5 evenly distributed fiber Bragg gratings (FBG) are arranged in different blood vessel segments; the signal detection system receives the wavelength reflected from (FBG) and generates a corresponding time-varying output signal. The receiving end (PP) will obtain the flow and flow velocity (LS) of the simulated blood flow. The wavelength (λ) change at each position along the optical fiber (FB) is calculated according to the reflected wavelength (λ) and time characteristics, and converted into a strain signal output (μ), so as to determine the position and size of the vascular stenosis (XZ) and distortion (JB) area. The flow pump simulating blood flow can be a Doppler flow blood flow simulation system, which simulates the blood velocity, direction, flow and sensitivity. It also includes color ultrasound, which rechecks the detection results of the FBG sensor module. The FBG sensor module includes a spatial fiber morphology FBG multi-point grating array, the FBG sensor module can enter a blood vessel with a diameter of 4mm-8mm, and the bending degree of the FBG sensor module is ±120°. The curved blood vessel stenosis model includes a mounting box and a plurality of blood flow channels, wherein: a plurality of mounting holes are provided on two opposite sides of the mounting box, and a plurality of blood flow channels are installed in the mounting box through the mounting holes; a narrow area is cast in the middle of some blood flow channels, and the narrow areas cast in the middle of different blood flow channels are different. A three-way joint is provided on the side of the mounting box, and the FBG sensor module is arranged in one of the joints. The Doppler flow blood flow simulation system is connected to the curved blood vessel stenosis model, and the curved blood vessel stenosis model is connected to the waste liquid recovery system through acrylic tubes. The signal detection system includes a liquid pressure sensor and a liquid flow sensor. The liquid pressure sensor detects the pressure of the simulated blood flow in the acrylic tube; the liquid flow sensor detects the flow rate of the simulated blood flow in the acrylic tube.

[0031] To further explain, the present invention constructs a multimodal test system integrating FBG sensor, signal analysis system, Doppler flow blood flow simulation system, and curved blood vessel stenosis model. In order to study the relationship between the stress-strain signal of the FBG sensor and the changes in blood vessel pressure, flow, and flow velocity caused by vascular distortion and stenosis, the blood flow function simulation system is used to change the pressure and viscosity of the liquid, simulating changes in blood pressure and flow velocity.

[0032] Construct a Doppler flow pump blood flow simulation system used in conjunction with a simulated curved vascular stenosis model to simulate the research and engineering tests of blood flow velocity, direction, flow rate, and sensitivity. Simulate the physiological waveforms produced by constant flow or pulsating flow of blood materials; select a formula that can simulate the physical properties of human blood, a reliable, stable, and harmless Doppler fluid, and use it in conjunction with an ultrasound Doppler flow model system to evaluate the system performance of a Doppler imaging system. Compare the signal response of FBG sensors in the test.

[0033] The curved blood vessel stenosis model is the basis for effective experiments. The model of the present invention is composed of a rubber-based tissue simulation material, which can avoid melting, freezing, dehydration and falling off. It contains 4 blood flow channels that simulate the vascular system, 4 flow channels, and casts a part of the stenosis area respectively. For example: the inner diameter of the blood vessel is 4mm, with no stenosis, about 50% stenosis, and a stenosis length of 10mm; the inner diameter is 6mm, about 75% stenosis, and a stenosis length of 20mm; the inner diameter is 8mm, about 90% stenosis, and a length of 30mm. The outside of one side is connected to a three-way connector, one port is filled with liquid to form a closed loop, and one port can enter the FBG sensor. The whole is embedded in a box for easy testing.

[0034] According to the need to perceive the changes in the spatial posture of blood vessels, a spatial fiber-shaped FBG multi-point grating array is constructed and integrated into the robot's catheter body, and an integration method for the optical fiber at the guidewire head is designed to enable multi-point perception of deformed lesions. A bending-strain model is established, and shape reconstruction is estimated through linear or cubic interpolation, and the FBG strain readings are converted into high-precision and high-resolution force information to form a continuous multi-grating array of multi-core curved optical fibers. Figure 3 The FBG fiber grating string array changes with the spatial curvature of the blood vessel.

[0035] Due to differences in age, gender, and body shape, vascular stenosis has uncertainties in area, scale, and degree of lesions. Most human blood vessels and cavities are small and long, and often contain body fluids or media. In medical diagnosis and treatment, longer guidewires work in a changing environment, and the closed nature of the internal tubes further increases the difficulty of morphological detection.

[0036] The FBG multi-core fiber grating array of the present invention changes the spatial morphology of blood vessels. It can enter blood vessels with a diameter of 4mm-8mm, and the bending degree is ±120 degrees. The FBG multi-core fiber grating array of the present invention has a certain degree of spatial distortion; it has good spatial flexibility and strength, has no metal accessories, and can enter the magnetic resonance MRI environment test. The present invention can obtain the strain signal of the corresponding flow and flow velocity changes caused by blood vessel distortion and stenosis through the change of the wavelength of the fiber Bragg grating. It is beneficial to be used for rapid scanning of arterial blood vessels to diagnose stenotic areas without relying on the radiation inspection of iodinated contrast agents. It can obtain efficient inspection results of vascular stenosis diseases.

[0037] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A FBG-based vascular stenosis sensing system, characterized in that: It includes a flow pump for simulating blood flow, a multi-point bendable FBG sensor module, a curved blood vessel stenosis model, a waste liquid recovery system, a signal detection system and a signal analysis system, wherein: A flow pump simulating blood flow, a curved blood vessel stenosis model, and a waste fluid recovery system are connected in sequence; The FBG sensor module is inserted into the vascular distortion model; The signal detection system detects the flow rate and strain of the simulated blood flow; The signal analysis system receives data from the FBG sensor module and the signal detection system, and the analysis system analyzes the relationship between the stress-strain signal of the sensor FBG and the vascular strain caused by vascular distortion and stenosis; The multi-point bendable FBG sensor module includes a spatial optical fiber morphology FBG multi-point grating array; There are multiple FBG multi-point gratings, which can enter blood vessels with a diameter of 4mm-8mm. The bending degree of the FBG sensor module is ±120°; The curved blood vessel stenosis model comprises a mounting box and a plurality of curved blood flow channels, wherein: a plurality of mounting holes are arranged on two opposite sides of the mounting box, and the plurality of blood flow channels are mounted in the mounting box through the mounting holes; Some blood flow channels have narrow areas cast in the middle, and different blood flow channels have different narrow areas cast in the middle; The signal detection system comprises a liquid pressure sensor and a liquid flow sensor. The liquid pressure sensor detects the pressure of the simulated blood flow in the acrylic tube; the liquid flow sensor detects the flow rate of the simulated blood flow in the acrylic tube.

2. The FBG-based vascular stenosis sensing system according to claim 1, characterized in that: It also includes color ultrasound, which rechecks the detection results of the FBG sensor module.

3. The FBG-based vascular stenosis sensing system according to claim 1, characterized in that: A three-way joint is arranged on the side of the installation box, and the FBG sensor module is arranged in one of the joints.

4. The FBG-based vascular stenosis sensing system according to claim 1, characterized in that: The flow pump simulating blood flow and the curved blood vessel stenosis model, and the curved blood vessel stenosis model and the waste liquid recovery system are connected through acrylic tubes.

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