Method, system, device and medium for detecting rotation synchronization of OCT catheter

Abstract

The present invention discloses a method, system, device and medium for detecting the rotation synchronization of an OCT catheter. The method comprises obtaining a real-time catheter end face image of an OCT catheter in a simulated blood vessel, extracting features from the real-time catheter end face image to obtain real-time coordinates of at least two feature points; matching feature points according to the real-time coordinates of at least two feature points to obtain a real-time rotation angle and a real-time offset displacement; calculating the instantaneous rotation speed according to the real-time rotation angle; calculating the cumulative offset displacement of one rotation according to the real-time offset displacement; obtaining the device rotation speed, obtaining a rotation score value according to the instantaneous rotation speed and the device rotation speed; obtaining a jitter score value according to the real-time offset displacement and the cumulative offset displacement; and obtaining the synchronization performance level of the OCT catheter according to the rotation score value and the jitter score value. The present invention realizes accurate detection of the synchronization and uniformity between the device end and the OCT catheter, and the detection result is more comprehensive, accurate and reliable.

Description

Technical Field

[0001] The present invention relates to the technical field of medical equipment, and in particular to a method, system, device and medium for detecting rotation synchronization of an OCT catheter. Background Art

[0002] The OCT catheter, or Optical Coherence Tomography catheter, is an advanced medical imaging technology device. The main component of the OCT catheter is an imaging probe with a light source. The working principle is to place the OCT catheter into the blood vessel, use the built-in light source of the imaging probe to emit near-infrared light, and receive the light signal reflected from the vessel wall tissue. The reflected light signal is reconstructed to generate a high-resolution image of the blood vessel, thereby clearly showing the structure, thickness and pathological conditions of the vessel wall.

[0003] During the operation of the OCT catheter, the motion controller on the device side is required to provide power for the imaging probe to control its rotation and retraction. The specific control process is as follows: the drive motor of the motion controller drives the OCT catheter to rotate, and the OCT catheter is imaged in real time during the retraction process. During the retraction process, the drive motor first accelerates from low speed to high speed, driving the OCT catheter from low speed to high speed. When the high-speed rotation is stable, the OCT catheter is pulled back, and the high-speed camera is aimed at the end face of the OCT catheter to generate retraction image data. In the above control process, the stability of the rotation speed of the OCT catheter will affect the imaging quality. When the rotation speed of the motion controller on the device side is not synchronized with the rotation speed of the OCT catheter, the rotation speed of the OCT catheter will become non-uniform, and the OCT catheter will have variable stress, causing the OCT catheter to shake during the acceleration stage, and the rotation speed of the OCT catheter is not uniform during the retraction stage. The image will deform, slip, shake, and other abnormalities, affecting the accuracy of imaging and clinical diagnosis.

[0004] In traditional technology, the rotation speed is usually detected by the encoder built into the motion controller on the device side. However, this rotation speed can only reflect the rotation speed on the device side, but cannot reflect the actual rotation speed during the rotation of the OCT catheter. Moreover, it can only detect the rotation speed, but cannot determine the synchronization and uniformity between the device side and the OCT catheter, and cannot avoid images generated under abnormal conditions such as deformation, slippage, and jitter.

[0005] Therefore, there is an urgent need for a new technology that can detect the synchronization and uniformity between the device end and the OCT catheter, screen out unqualified OCT catheters, and avoid images generated under abnormal conditions such as deformation, slippage, and jitter that affect clinical diagnosis. Summary of the invention

[0006] In view of this, the present invention provides a method, system, device and medium for detecting the rotation synchronization of an OCT catheter, so as to solve the problem that in traditional OCT catheter technology, the rotation speed of the device is detected only by the encoder on the device end, resulting in an inability to judge the synchronization and uniformity between the device end and the OCT catheter, and an inability to avoid the images generated under abnormal conditions such as deformation, slippage, and jitter affecting clinical diagnosis.

[0007] The present invention provides a method for detecting rotation synchronization of an OCT catheter, wherein the OCT catheter is provided with a motion controller, and the method comprises:

[0008] Acquire a real-time catheter end surface image of the OCT catheter in the simulated blood vessel within a set time period, perform feature extraction on the real-time catheter end surface image, and obtain real-time coordinates of at least two feature points;

[0009] Performing feature point matching according to the real-time coordinates of at least two feature points to obtain a real-time rotation angle and a real-time offset displacement of the OCT catheter;

[0010] According to the real-time rotation angle, the instantaneous rotation speed of the OCT catheter is calculated; according to the real-time offset displacement, the accumulated offset displacement of the OCT catheter when it rotates one circle is calculated;

[0011] Obtaining a device rotation speed corresponding to the motion controller, and obtaining a rotation score value corresponding to the OCT catheter according to the instantaneous rotation speed and the device rotation speed; and obtaining a jitter score value corresponding to the OCT catheter according to the real-time offset displacement and the accumulated offset displacement;

[0012] The synchronization performance level of the OCT catheter is obtained according to the rotation score value and the jitter score value.

[0013] Optionally, obtaining a rotation score value corresponding to the OCT catheter according to the instantaneous rotation speed and the device rotation speed includes:

[0014] According to the instantaneous rotation speed, respectively calculating the instantaneous rotation speed mean square error and the average rotation speed of the OCT catheter within a set time period;

[0015] Calculating the absolute value difference between the average rotation speed and the rotation speed of the device;

[0016] It is determined whether the absolute difference in rotation speed satisfies a first preset criterion and whether the mean square error of the instantaneous rotation speed satisfies a second preset criterion, and the rotation score value corresponding to the OCT catheter is determined according to the satisfaction.

[0017] Optionally, the rotation score value has a first initial score value;

[0018] Determining the rotation score value corresponding to the OCT catheter according to the satisfied condition includes:

[0019] When the absolute difference in rotation speed meets the first preset criterion, the first initial score value of the rotation score value is accumulated according to the first score value; otherwise, the first initial score value of the rotation score value is accumulated according to the second score value to obtain a first rotation score;

[0020] When the instantaneous rotation speed mean square error satisfies the second preset criterion, the first initial score value of the rotation score value is accumulated according to the third score value; otherwise, the first initial score value of the rotation score value is accumulated according to the fourth score value to obtain a second rotation score;

[0021] The rotation score value corresponding to the OCT catheter is obtained according to the first rotation score and the second rotation score.

[0022] Optionally, the specific expression of the first preset criterion is: ;

[0023] Wherein, R0 is the rotation speed of the equipment, is the average speed, r1 is the first preset threshold;

[0024] And / or, the specific expression of the second preset criterion is: ;

[0025] Among them, MSE R is the instantaneous speed mean square error, and r2 is the second preset threshold.

[0026] Optionally, the method further comprises:

[0027] Determining whether the absolute difference in rotation speed satisfies the first preset criterion;

[0028] When the absolute difference in rotation speed does not satisfy the first preset criterion, determining that the OCT catheter is rotationally unstable;

[0029] When the absolute difference in rotation speed satisfies the first preset criterion, it is determined whether the instantaneous rotation speed mean square error satisfies the second preset criterion. If so, it is determined that the OCT catheter rotation is stable; otherwise, it is determined that the OCT catheter rotation is unstable.

[0030] Optionally, the real-time offset displacement includes the real-time lateral displacement and the real-time longitudinal displacement of the OCT catheter in each frame within the set time period, and the cumulative offset displacement includes the cumulative lateral displacement and the cumulative longitudinal displacement when the OCT catheter rotates one circle within the set time period;

[0031] The step of obtaining a jitter score value corresponding to the OCT catheter according to the real-time offset displacement and the accumulated offset displacement includes:

[0032] Obtaining a first jitter determination result according to the real-time lateral displacement and the real-time longitudinal displacement of all frames;

[0033] Obtaining a second jitter determination result according to the accumulated lateral displacement and the accumulated longitudinal displacement;

[0034] Obtaining a jitter result of the OCT catheter according to the first jitter determination result and the second jitter determination result;

[0035] A jitter score value corresponding to the OCT catheter is determined according to the jitter result of the OCT catheter.

[0036] Optionally, obtaining a first jitter determination result according to the real-time lateral displacement and the real-time longitudinal displacement of all frames includes:

[0037] Selecting any one frame of the real-time lateral displacement and the real-time longitudinal displacement, and determining whether the selected real-time lateral displacement and the selected real-time longitudinal displacement are both less than a first offset threshold;

[0038] When the selected real-time lateral displacement and the real-time longitudinal displacement are both smaller than the first offset threshold, continue to judge whether the selected real-time lateral displacement and the real-time longitudinal displacement are both smaller than the second offset threshold; when the selected real-time lateral displacement and the real-time longitudinal displacement are both smaller than the second offset threshold, determine that the real-time jitter level of the OCT catheter at the selected frame is the first level; when at least one of the selected real-time lateral displacement and the real-time longitudinal displacement is not smaller than the second offset threshold, determine that the real-time jitter level of the OCT catheter at the selected frame is the second level; wherein the second offset threshold is smaller than the first offset threshold;

[0039] When at least one of the selected real-time lateral displacement and the selected real-time longitudinal displacement is not less than the first offset threshold, determining that the real-time jitter level of the OCT catheter at the selected frame is a third level;

[0040] According to the same method, determining the real-time jitter level of each frame of the OCT catheter;

[0041] Determining the real-time jitter level with the highest priority among the real-time jitter levels of all frames of the OCT catheter as the first jitter determination result;

[0042] The priorities of the first level, the second level and the third level increase in sequence, and the jitters represented by the first level, the second level and the third level increase in sequence.

[0043] Optionally, obtaining a second jitter determination result according to the accumulated lateral displacement and the accumulated longitudinal displacement includes:

[0044] Determining whether the accumulated lateral displacement and the accumulated longitudinal displacement are both less than a third offset threshold;

[0045] When the accumulated lateral displacement and the accumulated longitudinal displacement are both smaller than the third offset threshold, continue to judge whether the accumulated lateral displacement and the accumulated longitudinal displacement are both smaller than the fourth offset threshold; when the accumulated lateral displacement and the accumulated longitudinal displacement are both smaller than the fourth offset threshold, determine that the accumulated jitter level of the OCT catheter is the first level; when at least one of the accumulated lateral displacement and the accumulated longitudinal displacement is not smaller than the fourth offset threshold, determine that the accumulated jitter level of the OCT catheter is the second level; wherein the fourth offset threshold is smaller than the third offset threshold;

[0046] When at least one of the accumulated lateral displacement and the accumulated longitudinal displacement is not less than the third offset threshold, determining that the accumulated jitter level of the OCT catheter is the third level;

[0047] The accumulated jitter level of the OCT catheter is determined as the second jitter determination result.

[0048] Optionally, obtaining a jitter result of the OCT catheter according to the first jitter determination result and the second jitter determination result includes:

[0049] The real-time jitter level or the accumulated jitter level with the highest priority among the first jitter determination result and the second jitter determination result is determined as the jitter result of the OCT catheter.

[0050] Optionally, the jitter score value has a second initial score value;

[0051] Determining a jitter score value corresponding to the OCT catheter according to the jitter result of the OCT catheter includes:

[0052] When the jitter result of the OCT catheter is the first level, the second initial score value of the jitter score value is accumulated according to the fifth score value; when the jitter result of the OCT catheter is the second level, the second initial score value of the jitter score value is accumulated according to the sixth score value; when the jitter result of the OCT catheter is the third level, the second initial score value of the jitter score value is accumulated according to the seventh score value;

[0053] The jitter score value corresponding to the OCT catheter is obtained according to the accumulated second initial score value.

[0054] Optionally, obtaining the synchronization performance level of the OCT catheter according to the rotation score value and the jitter score value includes:

[0055] Accumulating the rotation score value and the jitter score value to obtain a synchronization index value of the OCT catheter;

[0056] When the synchronization index value is within a first index threshold range, determining that the synchronization performance level of the OCT catheter is a fourth level;

[0057] When the synchronization index value is within a second index threshold range, determining that the synchronization performance level of the OCT catheter is a fifth level;

[0058] When the synchronization index value is not within the first index threshold range and the second index threshold range, determining that the synchronization performance level of the OCT catheter is the sixth level;

[0059] The synchronization performance of the OCT catheter represented by the fourth level, the fifth level and the sixth level decreases in sequence.

[0060] Optionally, the OCT catheter is equipped with an image collector, and the real-time rotation angle includes the rotation angle of each frame of the OCT catheter within the set time period;

[0061] Calculating the instantaneous rotation speed of the OCT catheter according to the real-time rotation angle includes:

[0062] According to the real-time rotation angle, a minimum number of frames for the OCT catheter to rotate one circle within the set time period is calculated;

[0063] The time interval for the image collector to collect one frame of image is obtained in advance, and the instantaneous rotation speed of the OCT catheter is calculated according to the time interval and the minimum number of frames.

[0064] Optionally, a specific formula for calculating the minimum number of frames is:

[0065] ;

[0066] Where n is the minimum number of frames, θ i is the rotation angle of the OCT catheter at the i-th frame within the set time period;

[0067] The specific formula for calculating the instantaneous rotation speed is:

[0068] ;

[0069] Wherein, R is the instantaneous rotation speed, is the time interval.

[0070] Optionally, performing feature point matching according to the real-time coordinates of at least two feature points to obtain a real-time rotation angle and a real-time offset displacement of the OCT catheter includes:

[0071] Selecting two target feature points from the at least two feature points, and constructing a transformation equation group according to the real-time coordinates of the two selected target feature points;

[0072] The transformation equations are solved to obtain the real-time rotation angle and the real-time offset displacement of the OCT catheter.

[0073] Optionally, the real-time coordinates of the two selected target feature points in the jth frame are (x 1j ,y 1j ) and (x 2j ,y 2j ), the real-time coordinates of the two selected target feature points in the j+1 frame are (x 1j+1 ,y 1j+1 ) and (x 2j+1 ,y 2j+1 ), then the transformation equations of the OCT catheter constructed between the jth frame and the j+1th frame are specifically:

[0074] ;

[0075] Among them, θ j is the real-time rotation angle of the OCT catheter at the jth frame, (t xj , t yj ) is the real-time offset displacement of the OCT catheter at the jth frame.

[0076] Optionally, the OCT catheter is equipped with an image collector; the two characteristic points are specifically the center of the catheter and the center of the marking point;

[0077] The step of acquiring a real-time catheter end surface image of the OCT catheter in the simulated blood vessel within a set time period, and performing feature extraction on the real-time catheter end surface image to obtain real-time coordinates of at least two feature points includes:

[0078] Using the image collector, collecting in real time an initial image of the OCT catheter in the simulated blood vessel within the set time period;

[0079] Performing real-time foreground extraction on the initial image to obtain the real-time catheter end surface image;

[0080] The real-time catheter end face image is subjected to binarization processing and connected domain detection in sequence to obtain a catheter binarization mask image and a marker point binarization mask image respectively;

[0081] Performing contour extraction on the catheter binary mask image to obtain a catheter contour image; performing contour extraction on the marker point binary mask image to obtain a marker point contour image;

[0082] The catheter contour image is fitted with a minimum radius enclosing circle to obtain the real-time coordinates corresponding to the center of the catheter circle; the marker point contour image is fitted with a minimum radius enclosing circle to obtain the real-time coordinates corresponding to the center of the marker point circle.

[0083] In addition, the present invention also provides a system for detecting the rotational synchronization of an OCT catheter, which is applied to the aforementioned method for detecting the rotational synchronization of an OCT catheter, and the system comprises:

[0084] A feature extraction module, used to obtain a real-time catheter end surface image of the OCT catheter in the simulated blood vessel within a set time period, perform feature extraction on the real-time catheter end surface image, and obtain real-time coordinates of at least two feature points;

[0085] A feature matching module, used to perform feature point matching according to the real-time coordinates of at least two feature points to obtain a real-time rotation angle and a real-time offset displacement of the OCT catheter;

[0086] A rotation speed and displacement calculation module, used to calculate the instantaneous rotation speed of the OCT catheter according to the real-time rotation angle; and to calculate the cumulative offset displacement of the OCT catheter when it rotates one circle according to the real-time offset displacement;

[0087] A rotation and jitter evaluation module, used to obtain a device rotation speed corresponding to the motion controller, and obtain a rotation score value corresponding to the OCT catheter according to the instantaneous rotation speed and the device rotation speed; and obtain a jitter score value corresponding to the OCT catheter according to the real-time offset displacement and the cumulative offset displacement;

[0088] The synchronization evaluation module obtains the synchronization performance level of the OCT catheter according to the rotation score value and the jitter score value.

[0089] In addition, the present invention also provides another OCT catheter rotation synchronization detection system, comprising:

[0090] An image collector, used to collect real-time catheter end surface images of the OCT catheter in the simulated blood vessel within a set time period;

[0091] A processor is communicatively connected with the image collector and is used to receive the real-time catheter end surface image collected by the image collector; extract features from the real-time catheter end surface image to obtain real-time coordinates of at least two feature points; perform feature point matching according to the real-time coordinates of at least two feature points to obtain a real-time rotation angle and a real-time offset displacement of the OCT catheter; calculate the instantaneous rotation speed of the OCT catheter according to the real-time rotation angle; and calculate the cumulative offset displacement of the OCT catheter when it rotates one circle according to the real-time offset displacement;

[0092] A motion controller with a built-in encoder, which is in communication with the processor and is used to control the movement of the OCT catheter in the simulated blood vessel and detect the rotation speed of the device through the encoder;

[0093] The processor is further used to receive the device rotation speed detected by the encoder, and obtain a rotation score value corresponding to the OCT catheter based on the instantaneous rotation speed and the device rotation speed; and obtain a jitter score value corresponding to the OCT catheter based on the real-time offset displacement and the cumulative offset displacement; and obtain a synchronization performance level of the OCT catheter based on the rotation score value and the jitter score value.

[0094] In addition, the present invention also provides an OCT catheter rotation synchronization detection device, including a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the computer program implements the method steps in the aforementioned OCT catheter rotation synchronization detection method when executed.

[0095] In addition, the present invention also provides a computer storage medium, which includes: at least one instruction, which implements the method steps in the aforementioned method for detecting rotation synchronization of an OCT catheter when the instruction is executed by a computer.

[0096] The beneficial effects of the present invention are as follows: firstly, by acquiring a real-time catheter end face image, it is convenient to subsequently analyze the real-time rotation angle and real-time offset displacement of the OCT catheter in the simulated blood vessel based on the real-time catheter end face image, and the real-time rotation angle and real-time offset displacement obtained by the image analysis technology can more accurately reflect the actual movement of the OCT catheter; wherein the real-time rotation angle can reflect the instantaneous rotation characteristics of the OCT catheter in the rotational movement, and then the instantaneous rotation speed of the OCT catheter driven by the motion controller can be calculated, which is convenient for the subsequent analysis of the synchronization of the OCT catheter in the rotational movement according to the instantaneous rotation speed; and the real-time offset displacement can reflect the instantaneous translation characteristics of the OCT catheter in the translational movement, and at the same time based on the real-time The offset displacement can also calculate the cumulative offset displacement of the OCT catheter when it rotates one circle. The cumulative offset displacement reflects the translation characteristics of the OCT catheter when it rotates one circle. Therefore, by obtaining the real-time offset displacement and the cumulative offset displacement, it is convenient to conduct a subsequent comprehensive analysis of the synchronization in the translation movement of the OCT catheter. Based on the instantaneous rotation speed and the obtained device rotation speed of the motion controller, the synchronization of the OCT catheter rotation process is evaluated to obtain the corresponding rotation score value, and based on the real-time offset displacement and the cumulative offset displacement, the synchronization of the OCT catheter translation process is evaluated to obtain the corresponding jitter score value. Finally, the two score values ​​are combined to comprehensively evaluate the OCT catheter rotation synchronization, and the result is more comprehensive, accurate and reliable.

[0097] The OCT catheter rotation synchronization detection method, system, device and medium of the present invention realize accurate detection of synchronization and uniformity between the device end and the OCT catheter based on the real-time rotation angle and real-time offset displacement, rather than relying solely on the rotation speed detected by the built-in encoder of the motion controller. It can more accurately reflect the actual movement of the OCT catheter, and the detection results are more comprehensive, accurate and reliable. Unqualified OCT catheters can be screened out, and images generated under abnormal conditions such as deformation, slippage and shaking can be effectively prevented from affecting clinical diagnosis. BRIEF DESCRIPTION OF THE DRAWINGS

[0098] The features and advantages of the present invention will be more clearly understood by referring to the accompanying drawings, which are schematic and should not be construed as limiting the present invention in any way. In the accompanying drawings:

[0099] Figure 1 A flow chart showing a method for detecting rotation synchronization of an OCT catheter in a first embodiment of the present invention is shown;

[0100] Figure 2 It shows a frame of images of the catheter end surface and the marking points captured by the high-speed camera in the first embodiment of the present invention;

[0101] Figure 3 The first embodiment of the present invention is shown Figure 2A catheter contour image and a marker point contour image obtained by performing contour extraction on the corresponding image;

[0102] Figure 4 It shows 10 frames of rotation angles and 4 frames of real-time catheter end surface images captured by a high-speed camera when the OCT catheter rotates one circle in the first embodiment of the present invention;

[0103] Figure 5 A diagram showing the relationship between the real-time rotation angle and the number of frames of the OCT catheter during a number of rotations in the first embodiment of the present invention;

[0104] Figure 6 A graph showing the relationship between the instantaneous rotation speed of the OCT catheter and time obtained in Example 1 of the present invention is shown;

[0105] Figure 7 The figure shows the motion trajectory of the OCT catheter when it rotates one circle in the first embodiment of the present invention;

[0106] Figure 8 The figure shows a curve diagram of the displacement of the OCT catheter when it rotates one circle in the first embodiment of the present invention;

[0107] Fig. 9 A structural diagram of a detection system for OCT catheter rotation synchronization in a second embodiment of the present invention is shown;

[0108] Fig.10 A structural diagram of a system for detecting rotation synchronization of an OCT catheter in a third embodiment of the present invention is shown. DETAILED DESCRIPTION

[0109] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0110] In the embodiments of the present invention, the term "and / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent three situations: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0111] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0112] In the embodiments of the present invention, the term "plurality" refers to two or more than two, and other quantifiers are similar.

[0113] Embodiment 1

[0114] This embodiment provides a method for detecting the rotation synchronization of an OCT catheter. The OCT catheter is equipped with a motion controller, such as Figure 1 As shown, the method includes:

[0115] S1: acquiring a real-time catheter end surface image of the OCT catheter in a simulated blood vessel within a set time period, performing feature extraction on the real-time catheter end surface image, and obtaining real-time coordinates of at least two feature points;

[0116] S2: performing feature point matching according to the real-time coordinates of at least two feature points to obtain a real-time rotation angle and a real-time offset displacement of the OCT catheter;

[0117] S3: calculating the instantaneous rotation speed of the OCT catheter according to the real-time rotation angle; calculating the cumulative offset displacement of the OCT catheter when it rotates one circle according to the real-time offset displacement;

[0118] S4: obtaining a device rotation speed corresponding to the motion controller, and obtaining a rotation score value corresponding to the OCT catheter according to the instantaneous rotation speed and the device rotation speed; and obtaining a jitter score value corresponding to the OCT catheter according to the real-time offset displacement and the accumulated offset displacement;

[0119] S5: Obtaining a synchronization performance level of the OCT catheter according to the rotation score value and the jitter score value.

[0120] In this embodiment, firstly, by acquiring a real-time catheter end face image, it is convenient to subsequently analyze the real-time rotation angle and real-time offset displacement of the OCT catheter in the simulated blood vessel based on the real-time catheter end face image. The real-time rotation angle and real-time offset displacement obtained by image analysis technology can more accurately reflect the actual movement of the OCT catheter; the real-time rotation angle can reflect the instantaneous rotation characteristics of the OCT catheter in the rotational movement, and then the instantaneous rotation speed of the OCT catheter driven by the motion controller can be calculated, which is convenient for the subsequent analysis of the synchronization of the OCT catheter in the rotational movement according to the instantaneous rotation speed; and the real-time offset displacement can reflect the instantaneous translation characteristics of the OCT catheter in the translational movement, and based on the real-time offset displacement, the real-time rotation angle can reflect the instantaneous translation characteristics of the OCT catheter in the translational movement. The offset displacement can also be used to calculate the cumulative offset displacement of the OCT catheter when it rotates one circle. The cumulative offset displacement reflects the translational characteristics of the OCT catheter when it rotates one circle. Therefore, by obtaining the real-time offset displacement and the cumulative offset displacement, it is convenient to subsequently comprehensively analyze the synchronization in the translational motion of the OCT catheter; the synchronization of the OCT catheter rotation process is evaluated based on the instantaneous rotation speed and the acquired device rotation speed of the motion controller, and the corresponding rotation score value can be obtained, while the synchronization of the OCT catheter translation process is evaluated based on the real-time offset displacement and the cumulative offset displacement, and the corresponding jitter score value can be obtained; finally, the two score values ​​are combined to comprehensively evaluate the OCT catheter rotation synchronization, and the result is more comprehensive, accurate and reliable.

[0121] The method for detecting the rotation synchronization of the OCT catheter in this embodiment realizes accurate detection of the synchronization and uniformity between the device end and the OCT catheter based on the real-time rotation angle and the real-time offset displacement, rather than relying solely on the rotation speed detected by the built-in encoder of the motion controller. It can more accurately reflect the actual movement of the OCT catheter, and the detection result is more comprehensive, accurate and reliable. It can screen out unqualified OCT catheters and effectively avoid the images generated under abnormal conditions such as deformation, slippage and shaking from affecting clinical diagnosis.

[0122] It should be understood that the above detection method of this embodiment is to apply an OCT catheter (i.e., an optical coherence tomography catheter) provided with an imaging end to a simulated blood vessel. The OCT catheter is equipped with a tooling device, a motion controller, and an image collector. The tooling device is used to simulate the structure and characteristics of the blood vessel, including the bending, branching, and diameter change of the blood vessel. The catheter passes through the tooling device to simulate its tortuous path in the real blood vessel; the motion controller can accurately control the movement of the catheter, including rotation, propulsion, and positioning, to ensure that the imaging end can accurately scan the area to be observed. One end of the OCT catheter is connected to the motion controller, and the OCT catheter passes through the tooling device and performs a circuitous movement in the simulated blood vessel under the control of the motion controller, wherein the imaging end is pre-fixed at a specific position of the tooling device, which simulates a lumen of a certain diameter of a real blood vessel, and the image collector (specifically a high-speed camera) is aligned with the end face of the imaging end. When the OCT catheter emits light and receives reflected light from the vascular tissue, the high-speed camera can capture the information of the reflected light and convert it into digital image data.

[0123] Each step of the method for detecting the rotation synchronization of the OCT catheter in this embodiment is described in detail below.

[0124] Preferably, in this embodiment S1, obtaining a real-time catheter end face image of the OCT catheter in the simulated blood vessel within a set time period includes:

[0125] S11: using the image collector to collect in real time an initial image of the OCT catheter in the simulated blood vessel within the set time period;

[0126] S12: Performing real-time foreground extraction on the initial image to obtain the real-time catheter end surface image.

[0127] By acquiring the initial image through the above method and performing real-time foreground extraction on it, background factors unrelated to the catheter in the initial image can be removed, which helps to improve the efficiency and accuracy of subsequent image analysis.

[0128] Among them, foreground extraction is a conventional technology in image processing technology (such as color space conversion, threshold segmentation and other methods), and the specific details are not repeated here.

[0129] Preferably, in the present embodiment S1, two feature points are taken as target feature points, specifically the center of the catheter and the center of the marking point (where the marking point can be preset according to actual conditions), and then feature extraction is performed on the real-time catheter end surface image to obtain the real-time coordinates of at least two feature points, including:

[0130] S13: performing binarization processing and connected domain detection on the real-time catheter end surface image in sequence, and obtaining a catheter binarization mask image and a marker point binarization mask image respectively;

[0131] S14: performing contour extraction on the catheter binary mask image to obtain a catheter contour image; performing contour extraction on the marker point binary mask image to obtain a marker point contour image;

[0132] S15: Fitting the minimum radius enclosing circle to the catheter contour image to obtain the real-time coordinates corresponding to the center of the catheter circle; fitting the minimum radius enclosing circle to the marker point contour image to obtain the real-time coordinates corresponding to the center of the marker point circle.

[0133] After the real-time catheter end face image is obtained through foreground extraction, binarization processing is performed to convert each pixel in the image into black and white, which can simplify the image data and remove noise, making key features (such as edges, contours, etc.) more prominent, which is helpful for subsequent contour extraction and feature point matching; then connected domain detection is performed to identify the image area composed of foreground pixels with the same pixels and adjacent positions in the real-time catheter end face image after binarization processing, which can further help to accurately extract the contour information of the catheter end face and the marking points, and obtain accurate catheter contour images and marking point contour images; the minimum radius enclosing circle fitting method can accurately find the minimum circle that can contain all catheter end faces or marking point contour points, and can accurately fit the actual positions of the catheter center and the marking point center, with accurate results, strong robustness and high computational efficiency.

[0134] The image collector of this embodiment is specifically a high-speed camera. The relevant parameters of the high-speed camera can be set in advance according to the actual situation. For example, the rotation speed specification of the OCT catheter usually requires 100 r / s, so the acquisition frame rate of the high-speed camera is set to 1000fps. Correspondingly, 10 frames of the end face image of the imaging end of the OCT catheter can be collected when the OCT catheter rotates one circle (specifically using The set time period may refer to a specific time (such as 10 seconds) or the time corresponding to a certain number of rotations of the OCT catheter (such as the time corresponding to 10 rotations).

[0135] Specifically, the high-speed camera of this embodiment collects a frame of images of the catheter end surface and the marking points, such as Figure 2 As shown, Figure 2 The solid line box represents the marker point, and the dotted line box represents the catheter end face. The catheter contour image and the marker point contour image after contour extraction are shown in Figure 2. Figure 3 As shown, Figure 3 Contour A is the catheter contour, and contour B is the marker point contour.

[0136] It should be understood that the above steps S11 to S15 of this embodiment are all real-time processing processes. For each frame of the initial image collected by the image collector, real-time processing is performed. The obtained catheter contour image and marker point contour image are images in each frame, and then the real-time coordinates corresponding to the catheter center and the real-time coordinates corresponding to the marker point center are also coordinates in each frame. For example, when the OCT catheter rotates one circle, the high-speed camera can collect 10 frames of initial images, and the corresponding 10 frames of real-time catheter end surface images are as follows: Figure 4 As shown ( Figure 4 Only four frames of real-time catheter end surface images of the OCT catheter from 0°→36°, 36°→72°, 72°→108°, and 108°→144° are shown. The remaining six frames are the same and are omitted and not shown). The 10 angles in the figure represent the angles of the OCT catheter in 10 frames during one rotation.

[0137] The above-mentioned feature points are taken as examples of the center of the catheter and the center of the marking point, which can better reflect the actual movement of the OCT catheter. Of course, in actual situations, other feature points can also be selected, and their feature extraction process is the same as that of the center of the catheter and the center of the marking point.

[0138] Preferably, this embodiment S2 includes:

[0139] S21: selecting two target feature points from the at least two feature points, and constructing a transformation equation group according to the real-time coordinates of the two selected target feature points;

[0140] S22: Solving the transformation equation group to obtain the real-time rotation angle and real-time offset displacement of the OCT catheter.

[0141] The real-time coordinates of the two selected target feature points are transformed to construct a transformation equation group before and after the transformation. Since the transformation equation group is established on the premise of satisfying the motion law of the OCT catheter, the corresponding relationship between the two target feature points can be found out by solving the transformation equation group, and then the motion law of the OCT catheter can be determined, that is, the rotation and small movement of the OCT catheter can be captured, and the real-time rotation angle and real-time offset displacement of the OCT catheter can be obtained, so as to achieve high-precision positioning of the OCT catheter, and facilitate the subsequent synchronization evaluation of the rotation process and the translation process of the OCT catheter based on the real-time rotation angle and real-time offset displacement.

[0142] Specifically, suppose the real-time coordinates of the two selected target feature points in the jth frame are (x 1j ,y 1j ) and (x 2j ,y 2j ), the real-time coordinates of the two selected target feature points in the j+1 frame are (x 1j+1,y 1j+1 ) and (x 2j+1 ,y 2j+1 ), then the transformation equations of the OCT catheter constructed between the jth frame and the j+1th frame are specifically:

[0143] ;

[0144] Among them, θ j is the real-time rotation angle of the OCT catheter at the jth frame, (t xj , t yj ) is the real-time offset displacement of the OCT catheter at the jth frame.

[0145] Similarly, the center of the catheter and the center of the marking point are used as two target feature points. The real-time coordinates of the two target feature points in the jth frame and the real-time coordinates of the j+1th frame are substituted into the equation group to solve the real-time rotation angle and real-time offset displacement of the OCT catheter in the jth frame.

[0146] In the same way, the real-time rotation angle and real-time offset displacement of the OCT catheter in each frame within a set time period can be obtained, such as Figure 5 As shown, Figure 5 This is a graph showing the relationship between the real-time rotation angle and the number of frames when the OCT catheter is rotated several times, wherein the horizontal axis is the number of frames and the vertical axis is the real-time rotation angle.

[0147] Preferably, in this embodiment S3, calculating the instantaneous rotation speed of the OCT catheter according to the real-time rotation angle includes:

[0148] S31: Calculating the minimum number of frames for the OCT catheter to rotate one circle within the set time period according to the real-time rotation angle;

[0149] S32: Pre-acquire the time interval for the image collector to acquire a frame of image, and calculate the instantaneous rotation speed of the OCT catheter according to the time interval and the minimum number of frames.

[0150] Since the angle of one rotation of the OCT catheter is the accumulation of real-time rotation angles under multiple frames, the minimum number of frames for one rotation of the OCT catheter can be obtained based on the accumulation of real-time rotation angles. Then, the total time (equivalent to the period) taken by the OCT catheter to rotate one circle can be known by using the time interval for a given image acquisition device to capture a frame of image and the minimum number of frames obtained. The instantaneous rotation speed of the OCT catheter can be obtained using this total time.

[0151] Specifically, in S31, the specific formula for calculating the minimum number of frames is:

[0152] ;

[0153] Where n is the minimum number of frames, θ i is the rotation angle of the OCT catheter at the i-th frame within the set time period;

[0154] In S32, the specific formula for calculating the instantaneous rotation speed is:

[0155] ;

[0156] Wherein, R is the instantaneous speed, is the time interval.

[0157] The relationship between the instantaneous rotation speed and time of the OCT catheter obtained in this embodiment is shown in FIG. Figure 6 As shown, Figure 6 The horizontal axis is time, and the vertical axis is instantaneous speed.

[0158] Preferably, in this embodiment S3, calculating the cumulative offset displacement of the OCT catheter when it rotates one circle according to the real-time offset displacement includes:

[0159] S33: Calculate the cumulative offset displacement when the OCT catheter rotates one circle according to the real-time offset displacement and the minimum number of frames when the OCT catheter rotates one circle within the set time period.

[0160] In the aforementioned process of calculating the instantaneous rotation speed, the minimum number of frames for the OCT catheter to rotate one circle has been obtained, and the real-time offset displacement represents the offset displacement of the OCT catheter in each frame. Therefore, by accumulating the offset displacement corresponding to the minimum number of frames, the cumulative offset displacement of the OCT catheter when it rotates one circle can be obtained.

[0161] The specific formula for calculating the cumulative offset displacement is as follows:

[0162] ;

[0163] Where S is the cumulative displacement of the OCT catheter during one rotation, s i is the offset displacement of the OCT catheter at the i-th frame.

[0164] The motion trajectory diagram and the offset displacement curve diagram of the OCT catheter obtained in this embodiment when it rotates one circle are shown as follows: Figure 7 and Figure 8 As shown, in Figure 7 In the figure, the horizontal axis represents the actual horizontal position of the center of the catheter, and the vertical axis represents the actual longitudinal position of the center of the catheter; Figure 8 In the figure, the horizontal axis represents the real-time lateral displacement of the center of the catheter, and the vertical axis represents the real-time longitudinal displacement of the center of the catheter.

[0165] Specifically, in the present embodiment S4, the device rotation speed of the motion controller is directly detected by a built-in encoder. The specific detection method is a conventional function of the encoder, and the specific details are not repeated here.

[0166] Preferably, in this embodiment S4, obtaining the rotation score value corresponding to the OCT catheter according to the instantaneous rotation speed and the device rotation speed includes:

[0167] S41: calculating the instantaneous rotation speed mean square error and the average rotation speed of the OCT catheter within a set time period according to the instantaneous rotation speed;

[0168] S42: Calculate the absolute value difference between the average rotation speed and the rotation speed of the device;

[0169] S43: respectively judging whether the absolute difference in rotation speed satisfies a first preset criterion and whether the mean square error of the instantaneous rotation speed satisfies a second preset criterion, and determining the rotation score value corresponding to the OCT catheter according to the satisfaction.

[0170] The mean square error is an important indicator for measuring the degree of data dispersion. During the rotation of the OCT catheter, the instantaneous speed mean square error can reflect the degree of speed fluctuation. The smaller the instantaneous speed mean square error, the more stable the speed. Therefore, using the instantaneous speed mean square error to evaluate the synchronization of the rotation process can improve the accuracy of the evaluation. The absolute value difference of the speed can directly reflect the range of speed change within a certain period of time. Therefore, the stability of the OCT catheter rotation can also be intuitively judged based on the absolute value difference of the speed. This embodiment combines the judgment of the instantaneous speed mean square error and the absolute difference of the speed to effectively improve the accuracy of the rotation evaluation.

[0171] Specifically, in S41, the average speed of the OCT catheter within the set time period is calculated based on the instantaneous speed by using the average method. , and then use the mean square error method to substitute the average speed and instantaneous speed into the mean square error (MSE) of the instantaneous speed of the OCT catheter within the set time period. R .

[0172] Specifically, in S42, the absolute value difference of the rotation speed is , where R0 is the rotation speed of the device.

[0173] Specifically, in S43, the specific expression of the first preset criterion is: ;

[0174] Wherein, R0 is the rotation speed of the equipment, is the average speed, r1 is the first preset threshold;

[0175] And / or, the specific expression of the second preset criterion is: ;

[0176] Among them, MSE R is the instantaneous speed mean square error, and r2 is the second preset threshold.

[0177] By respectively presetting the thresholds corresponding to the absolute value difference of the speed and the instantaneous speed mean square error (ie, r1 and r2), it is convenient, direct and efficient to judge whether the absolute value difference of the speed and the instantaneous speed mean square error meet the requirements of speed stability.

[0178] The first preset threshold r1 and the second preset threshold r2 are both preset and adjusted according to actual conditions and are not limited here.

[0179] Specifically, the rotation score value has a first initial score value (eg, 0); by setting the first initial score value, it is convenient to perform cumulative scoring directly according to the satisfaction of the absolute value difference of the rotation speed and the instantaneous rotation speed mean square error, which is efficient and easy to execute.

[0180] In the above S43, determining the rotation score value corresponding to the OCT catheter according to the satisfied condition includes:

[0181] S431a: When the absolute difference in rotation speed meets the first preset criterion, the first initial score value of the rotation score value is accumulated according to the first score; otherwise, the first initial score value of the rotation score value is accumulated according to the second score to obtain a first rotation score;

[0182] S431b: When the instantaneous rotation speed mean square error meets the second preset criterion, the first initial score value of the rotation score value is accumulated according to the third score; otherwise, the first initial score value of the rotation score value is accumulated according to the fourth score to obtain a second rotation score;

[0183] S432: Obtaining the rotation score value corresponding to the OCT catheter according to the first rotation score and the second rotation score.

[0184] When the absolute difference in rotation speed meets the first preset criterion, it means that the rotation speed of the OCT catheter during rotation is relatively stable based on the absolute difference in rotation speed, and the first score can be accumulated on the basis of the first initial score; otherwise, it means that the rotation speed of the OCT catheter during rotation is relatively unstable, and the second score is accumulated. Similarly, when the instantaneous rotation speed mean square deviation meets the second preset criterion, it means that the rotation speed of the OCT catheter during rotation is relatively stable based on the instantaneous rotation speed mean square deviation, and the third score can be accumulated on the basis of the first initial score; otherwise, it means that the rotation speed of the OCT catheter during rotation is relatively unstable, and the fourth score is accumulated. Through the above scoring rules, the synchronization evaluation of the OCT catheter during rotation can be efficiently realized, and a rotation score that conforms to the actual movement of the OCT catheter can be obtained. Furthermore, it is convenient to combine the jitter score of the OCT catheter to comprehensively evaluate its synchronization performance.

[0185] It should be understood that the above-mentioned determination of the absolute speed difference and the instantaneous speed mean square error (i.e., step S431a and step S431b) can be performed simultaneously or sequentially. When performed simultaneously, in step S432, the accumulated first initial score value (i.e., the first rotation score) obtained based on the determination of the absolute speed difference and the accumulated first initial score value (i.e., the second rotation score) obtained based on the determination of the instantaneous speed mean square error are accumulated again to obtain the final rotation score value; and when performed sequentially, for example, the determination of the absolute speed difference is performed first and then the determination of the instantaneous speed mean square error is performed (the determination of the instantaneous speed mean square error first and then the determination of the absolute speed difference is similar, and will not be repeated here), the accumulated first initial score value (i.e., the first rotation score) obtained based on the determination of the absolute speed difference will cause the first initial score value to be updated, and the accumulation of the first initial score value based on the determination of the absolute speed difference is for the updated first initial score value (i.e., the first rotation score).

[0186] The above-mentioned first initial scoring value, first score, second score, third score and fourth score can all be pre-set and adjusted according to actual conditions, wherein the first score is different from the second score, the third score is different from the fourth score, and the first score and the third score can be the same or different, and the second score and the fourth score can be the same or different.

[0187] For example, in the first optional embodiment, the first initial score value of the rotation score value is assumed to be 0, the first score value and the third score value are both 0, and the second score value and the fourth score value are both 1. For the case where the absolute speed difference is first determined and then the instantaneous speed mean square error is determined (the determination of the instantaneous speed mean square error is first determined and then the absolute speed difference is determined, which is not repeated here), when the absolute speed difference meets the first preset criterion, the first rotation score obtained on the basis of the first initial score value is 0, otherwise it is 1. At this time, the first initial score value is updated, which is the same as the first rotation score, that is, 0 or 1, and the instantaneous speed mean square error is continued to be determined. When the absolute speed difference meets the first preset criterion and the instantaneous speed mean square deviation also meets the second preset criterion, the rotation score value obtained based on the first rotation score is 0 (0+0=0); when the absolute speed difference meets the first preset criterion and the instantaneous speed mean square deviation does not meet the second preset criterion, the rotation score value obtained based on the first rotation score is 1 (0+1=1); when the absolute speed difference does not meet the first preset criterion and the instantaneous speed mean square deviation meets the second preset criterion, the rotation score value obtained based on the first rotation score is 1 (1+0=1); when the absolute speed difference does not meet the first preset criterion and the instantaneous speed mean square deviation does not meet the second preset criterion, the rotation score value obtained based on the first rotation score is 2 (1+1=2). In the case where the absolute speed difference and the instantaneous speed mean square error are judged at the same time, when the absolute speed difference meets the first preset criterion and the instantaneous speed mean square error meets the second preset criterion, the first rotation score and the second rotation score obtained on the basis of the first initial score value are both 0, and the corresponding rotation score value is 0 (0+0=0); when the absolute speed difference meets the first preset criterion and the instantaneous speed mean square error does not meet the second preset criterion, the first rotation score and the second rotation score obtained on the basis of the first initial score value are respectively 0 and 1, and the corresponding rotation score value is The score is 1 (0+1=1); when the absolute speed difference does not meet the first preset criterion and the instantaneous speed mean square deviation meets the second preset criterion, the first rotation score and the second rotation score obtained on the basis of the initial first initial score value are 1 and 0 respectively, and the corresponding rotation score is 1 (1+0=1); when the absolute speed difference does not meet the first preset criterion and the instantaneous speed mean square deviation does not meet the second preset criterion, the first rotation score and the second rotation score obtained on the basis of the initial first initial score value are both 1, and the corresponding rotation score is 2 (1+1=2).

[0188] In the first optional embodiment described above, the higher the rotation score value finally obtained is, the more unstable the rotation speed of the OCT catheter is during its rotation.

[0189] For another example, in the second optional embodiment, the first initial score value of the rotation score value is assumed to be 0, the first score value and the third score value are both 1, and the second score value and the fourth score value are both 0. For the case where the absolute speed difference is first determined and then the instantaneous speed mean square error is determined (the determination of the instantaneous speed mean square error is first determined and then the absolute speed difference is determined, which is not repeated here), when the absolute speed difference meets the first preset criterion, the first rotation score obtained on the basis of the first initial score value is 1, otherwise it is 0. At this time, the first initial score value is updated, which is the same as the first rotation score, that is, 1 or 0, and the instantaneous speed mean square error is continued to be determined. When the absolute speed difference meets the first preset criterion and the instantaneous speed mean square deviation also meets the second preset criterion, the rotation score value obtained based on the first rotation score is 2 (1+1=2); when the absolute speed difference meets the first preset criterion and the instantaneous speed mean square deviation does not meet the second preset criterion, the rotation score value obtained based on the first rotation score is 1 (1+0=1); when the absolute speed difference does not meet the first preset criterion and the instantaneous speed mean square deviation meets the second preset criterion, the rotation score value obtained based on the first rotation score is 1 (0+1=1); when the absolute speed difference does not meet the first preset criterion and the instantaneous speed mean square deviation does not meet the second preset criterion, the rotation score value obtained based on the first rotation score is 0 (0+0=0). In the case of simultaneously judging the absolute speed difference and the instantaneous speed mean square error, when the absolute speed difference meets the first preset criterion and the instantaneous speed mean square error meets the second preset criterion, the first rotation score and the second rotation score respectively obtained on the basis of the first initial score value are both 1, and the corresponding rotation score value is 2 (1+1=1); when the absolute speed difference meets the first preset criterion and the instantaneous speed mean square error does not meet the second preset criterion, the first rotation score and the second rotation score respectively obtained on the basis of the first initial score value are 1 and 0, and the corresponding rotation score value is The score is 1 (1+0=1); when the absolute speed difference does not meet the first preset criterion and the instantaneous speed mean square deviation meets the second preset criterion, the first rotation score and the second rotation score obtained on the basis of the initial first initial score value are 0 and 1 respectively, and the corresponding rotation score is 1 (0+1=1); when the absolute speed difference does not meet the first preset criterion and the instantaneous speed mean square deviation does not meet the second preset criterion, the first rotation score and the second rotation score obtained on the basis of the initial first initial score value are both 0, and the corresponding rotation score is 0 (0+0=0).

[0190] In the above second optional embodiment, the higher the rotation score value finally obtained is, the more stable the rotation speed of the OCT catheter is during its rotation.

[0191] The same is true for other scores, which will not be listed here.

[0192] Preferably, in a first optional embodiment, the method further comprises:

[0193] Determining whether the absolute difference in rotation speed satisfies the first preset criterion;

[0194] When the absolute difference in rotation speed does not satisfy the first preset criterion, determining that the OCT catheter is rotationally unstable;

[0195] When the absolute difference in rotation speed satisfies the first preset criterion, it is determined whether the instantaneous rotation speed mean square error satisfies the second preset criterion. If so, it is determined that the OCT catheter rotation is stable; otherwise, it is determined that the OCT catheter rotation is unstable.

[0196] The above-mentioned first optional embodiment realizes the stability evaluation of the OCT catheter during the rotation process, which is specifically based on the method of first determining the absolute difference in rotation speed and then determining the mean square error of the instantaneous rotation speed. It can consider the synchronization of the OCT catheter from a unilateral perspective, facilitate the grasp of the unilateral performance of the OCT catheter, and contribute to the quality inspection of the catheter.

[0197] Preferably, in the second optional embodiment, the method further comprises:

[0198] Determining whether the instantaneous speed mean square error satisfies the second preset criterion;

[0199] When the instantaneous rotation speed mean square error does not satisfy the second preset criterion, determining that the OCT catheter is rotationally unstable;

[0200] When the instantaneous rotational speed mean square error satisfies the second preset criterion, it is determined whether the rotational speed absolute difference satisfies the first preset criterion. If so, it is determined that the OCT catheter rotation is stable; otherwise, it is determined that the OCT catheter rotation is unstable.

[0201] The above-mentioned second optional embodiment also realizes the stability evaluation of the OCT catheter during the rotation process, which is specifically based on the method of first determining the instantaneous speed mean square error and then determining the speed absolute difference. It can also consider the synchronization of the OCT catheter from a unilateral perspective, which is convenient for grasping the unilateral performance of the OCT catheter and is helpful for the quality inspection of the catheter.

[0202] Preferably, the real-time offset displacement includes the real-time lateral displacement and real-time longitudinal displacement of the OCT catheter in each frame within the set time period, and the cumulative offset displacement includes the cumulative lateral displacement and cumulative longitudinal displacement when the OCT catheter rotates one circle within the set time period.

[0203] The offset displacement of each frame and the accumulated offset displacement after one rotation are divided into two angles, namely, the horizontal angle and the vertical angle, which is helpful for the accurate evaluation of the synchronization of the subsequent OCT catheter during the translation process.

[0204] Preferably, in this embodiment S4, obtaining a jitter score value corresponding to the OCT catheter according to the real-time offset displacement and the cumulative offset displacement includes:

[0205] S44: obtaining a first jitter determination result according to the real-time lateral displacement and the real-time longitudinal displacement of all frames;

[0206] S45: obtaining a second jitter determination result according to the accumulated lateral displacement and the accumulated longitudinal displacement;

[0207] S46: Obtaining a jitter result of the OCT catheter according to the first jitter determination result and the second jitter determination result;

[0208] S47: Determine a jitter score value corresponding to the OCT catheter according to the jitter result of the OCT catheter.

[0209] Since the OCT catheter has instantaneous jitter and accumulated jitter during one rotation during its movement, there may be a situation where both the instantaneous jitter and the accumulated jitter are large, or there may be a situation where the instantaneous jitter is large but the accumulated jitter is small. Therefore, this embodiment comprehensively evaluates the synchronization of its translation process from two aspects: real-time offset displacement and accumulated offset displacement. When considering both the real-time offset displacement and the accumulated offset displacement, they are considered from two perspectives, namely, horizontal and vertical. This can greatly improve the accuracy of the final jitter score value and is more in line with the actual movement of the OCT catheter.

[0210] Specifically, step S44 includes:

[0211] S441: Selecting the real-time lateral displacement and the real-time longitudinal displacement of any one frame, and determining whether the selected real-time lateral displacement and the selected real-time longitudinal displacement are both less than a first offset threshold;

[0212] S442a: When the selected real-time lateral displacement and the real-time longitudinal displacement are both smaller than the first offset threshold, continue to determine whether the selected real-time lateral displacement and the real-time longitudinal displacement are both smaller than the second offset threshold; when the selected real-time lateral displacement and the real-time longitudinal displacement are both smaller than the second offset threshold, determine that the real-time jitter level of the OCT catheter at the selected frame is the first level; when at least one of the selected real-time lateral displacement and the real-time longitudinal displacement is not smaller than the second offset threshold, determine that the real-time jitter level of the OCT catheter at the selected frame is the second level; wherein the second offset threshold is smaller than the first offset threshold;

[0213] S442b: When at least one of the selected real-time lateral displacement and the selected real-time longitudinal displacement is not less than the first offset threshold, determining that the real-time jitter level of the OCT catheter at the selected frame is the third level;

[0214] S443: Determine the real-time jitter level of each frame of the OCT catheter in the same manner;

[0215] S444: determining the real-time jitter level with the highest priority among the real-time jitter levels of all frames of the OCT catheter as the first jitter determination result;

[0216] The priorities of the first level, the second level and the third level increase in sequence, and the jitters represented by the first level, the second level and the third level increase in sequence.

[0217] For the real-time lateral displacement and real-time longitudinal displacement of any frame, only when both are less than the second offset threshold, can its real-time jitter level be determined as the first level; and when one of them is not less than the second offset threshold and the other is less than the second offset threshold, or both are not less than the second offset threshold but both are less than the first offset threshold, its real-time jitter level is determined as the second level; when at least one of the two is not less than the first offset threshold (one is not less than the first offset threshold but the other is less than the first offset threshold, or both are not less than the first offset threshold), its real-time jitter level is determined as the third level; the real-time jitter level of each frame is determined according to the above method, which can realize the evaluation of the jitter condition of each frame during the OCT movement process. When the final instantaneous jitter is determined, the real-time jitter level with the highest priority in all frames is determined as the first jitter determination result corresponding to the instantaneous jitter, which is more in line with the actual movement of the OCT catheter; this embodiment realizes the determination of instantaneous jitter based on the two angles of real-time offset displacement according to the above method, and the obtained first jitter determination result is more accurate and reliable.

[0218] Specifically, since the jitters represented by the first level, the second level, and the third level increase in sequence, in an optional embodiment, the first level is embodied as no jitter, the second level is embodied as slight jitter, and the third level is embodied as severe jitter. At the same time, the first offset threshold is set to l1, the second offset threshold is set to l2, and l2<l1.

[0219] For the real-time lateral displacement t of the jth frame xj and real-time longitudinal displacement t yj , when t xj <l2 and t yj <l2, the real-time jitter level of the jth frame is determined to be no jitter; when t xj <l2 and l2≤t yj <l1、or l2≤t xj <l1 and t yj <l2、or l2≤t xj <l1 and l2≤t yj <l1, the real-time jitter level of the jth frame is judged to be slight jitter; when t xj ≥l1 and t yj <l1、or t xj <l1 and t yj ≥l1, or t xj ≥l1 and t yj ≥l1, the real-time jitter level of the jth frame is determined to be severe jitter.

[0220] When each frame obtains the corresponding real-time jitter level, the real-time jitter level with the highest priority among all frames is determined as the first jitter determination result. That is, when at least one frame among all frames has severe jitter, no matter what the real-time jitter levels of other frames are, the final first jitter determination result is severe jitter; when at least one frame among all frames has slight jitter and the rest of the frames are not jittering, the final first jitter determination result is slight jitter; when all frames are not jittering, the final first jitter determination result is not jitter.

[0221] It should be understood that the first offset threshold l1 and the second offset threshold l2 of this embodiment are both preset and adjusted according to actual conditions. And because the real-time lateral displacement and the real-time longitudinal displacement may have negative values, the numerical values ​​(i.e., values ​​without positive and negative signs) of the real-time lateral displacement and the real-time longitudinal displacement are used for comparison in the specific comparison of this embodiment. For the convenience of explanation, this embodiment takes the case where the real-time lateral displacement and the real-time longitudinal displacement are positive values ​​as an example.

[0222] Specifically, step S45 includes:

[0223] S451: Determine whether the accumulated lateral displacement and the accumulated longitudinal displacement are both less than a third offset threshold;

[0224] S452a: When the accumulated lateral displacement and the accumulated longitudinal displacement are both smaller than the third offset threshold, continue to determine whether the accumulated lateral displacement and the accumulated longitudinal displacement are both smaller than the fourth offset threshold; when the accumulated lateral displacement and the accumulated longitudinal displacement are both smaller than the fourth offset threshold, determine that the accumulated jitter level of the OCT catheter is the first level; when at least one of the accumulated lateral displacement and the accumulated longitudinal displacement is not smaller than the fourth offset threshold, determine that the accumulated jitter level of the OCT catheter is the second level; wherein the fourth offset threshold is smaller than the third offset threshold;

[0225] S452b: When at least one of the accumulated lateral displacement and the accumulated longitudinal displacement is not less than the third offset threshold, determining that the accumulated jitter level of the OCT catheter is the third level;

[0226] S453: Determine the accumulated jitter level of the OCT catheter as the second jitter determination result.

[0227] The above-mentioned method for determining the cumulative lateral displacement and the cumulative longitudinal displacement is similar to the method for determining the real-time lateral displacement and the real-time longitudinal displacement of any frame. For the cumulative lateral displacement and the cumulative longitudinal displacement of one rotation, the cumulative jitter level can be determined as the first level only when both are less than the fourth offset threshold; and when one of them is not less than the fourth offset threshold and the other is less than the fourth offset threshold, or both are not less than the fourth offset threshold but both are less than the third offset threshold, the cumulative jitter level is determined as the second level; when at least one of the two is not less than the third offset threshold (one is not less than the third offset threshold but the other is less than the third offset threshold, or both are not less than the third offset threshold), the cumulative jitter level is determined as the third level; the actual cumulative jitter level is determined as the second jitter determination result corresponding to the cumulative jitter, which also conforms to the actual movement of the OCT catheter, and the obtained second jitter determination result is more accurate and reliable.

[0228] Specifically, in an optional embodiment, the first level is also embodied as no shaking, the second level is embodied as slight shaking, and the third level is embodied as severe shaking. At the same time, the third offset threshold is set to l3, the fourth offset threshold is set to l4, and l4<l3.

[0229] For the cumulative lateral displacement S x and the cumulative longitudinal displacement S y , when S x <l4 and S y <l4, the cumulative jitter level is judged as no jitter; when S x <l4 and l4≤S y<l3、or l4≤S x <l3 and S y <l4、or l4≤S x <l3 and l4≤S y <l3, the cumulative jitter level is judged to be slight jitter; when S x ≥l3 and S y <l3, or S x <l3 and S y ≥l3, or S x ≥l3 and S y ≥l3, the accumulated jitter level is determined to be severe jitter. Finally, the accumulated jitter level is directly determined as the final second jitter determination result.

[0230] Similarly, the third offset threshold l3 and the fourth offset threshold l4 of this embodiment are preset and adjusted according to actual conditions. In the specific comparison of this embodiment, the values ​​(ie, values ​​without positive and negative signs) of the cumulative lateral displacement and the cumulative longitudinal displacement are taken for comparison.

[0231] Specifically, step S46 includes:

[0232] The real-time jitter level or the accumulated jitter level with the highest priority among the first jitter determination result and the second jitter determination result is determined as the jitter result of the OCT catheter.

[0233] When the first jitter determination result and the second jitter determination structure are determined according to the corresponding methods to obtain results, the level with the highest priority is determined as the result of the comprehensive evaluation of the synchronization evaluation during the translation of the OCT catheter.

[0234] Specifically, when the first level is concretized as no jitter, the second level is concretized as slight jitter, and the third level is concretized as severe jitter, if both the real-time jitter level and the cumulative jitter level are severe jitters, or only one of the real-time jitter level and the cumulative jitter level is severe jitter, the jitter result of the OCT catheter is severe jitter; if both the real-time jitter level and the cumulative jitter level are slight jitters, or one of the real-time jitter level and the cumulative jitter level is slight jitter and the other is no jitter, the jitter result of the OCT catheter is slight jitter; only when both the real-time jitter level and the cumulative jitter level are no jitter, the jitter result of the OCT catheter is no jitter.

[0235] Specifically, similar to the rotation score value, the jitter score value has a second initial score value.

[0236] The second initial scoring value facilitates subsequent cumulative scoring directly according to the jitter of the OCT catheter, which is efficient and easy to execute.

[0237] Specifically, step S47 includes:

[0238] S471: when the jitter result of the OCT catheter is the first level, accumulating the second initial score value of the jitter score value according to the fifth score; when the jitter result of the OCT catheter is the second level, accumulating the second initial score value of the jitter score value according to the sixth score; when the jitter result of the OCT catheter is the third level, accumulating the second initial score value of the jitter score value according to the seventh score;

[0239] S472: Obtain the jitter score value corresponding to the OCT catheter according to the accumulated second initial score value.

[0240] For the jitter score value, the score is directly calculated according to the level corresponding to the jitter result, which can efficiently realize the synchronization evaluation during the translation of the OCT catheter and obtain the jitter score value that conforms to the actual movement of the OCT catheter. Furthermore, it is convenient to combine the rotation score value of the OCT catheter to comprehensively evaluate its synchronization performance.

[0241] Similar to the first initial score value and the first to fourth scores, the second initial score value, the fifth score, the sixth score and the seventh score can also be pre-set and adjusted according to actual conditions, among which the fifth score, the sixth score and the seventh score are different from each other.

[0242] For example, in the first optional embodiment, the second initial score value of the jitter score value is 0, the fifth score value is 0, the sixth score value is 1, and the seventh score value is 2. Then, when the jitter result is the first level (such as no jitter), the jitter score value obtained by accumulating the second initial score value is 0; when the jitter result is the second level (such as slight jitter), the jitter score value obtained by accumulating the second initial score value is 1; when the jitter result is the third level (such as severe jitter), the jitter score value obtained by accumulating the second initial score value is 2. In the above first optional embodiment, the higher the final jitter score value, the greater the jitter during the translation of the OCT catheter, and the more unstable the translation.

[0243] For another example, in the second optional embodiment, the second initial score value of the jitter score value is 0, the fifth score value is 2, the sixth score value is 1, and the seventh score value is 0. Then when the jitter result is the first level (such as no jitter), the jitter score value obtained by accumulating the second initial score value is 2; when the jitter result is the second level (such as slight jitter), the jitter score value obtained by accumulating the second initial score value is 1; when the jitter result is the third level (such as severe jitter), the jitter score value obtained by accumulating the second initial score value is 0. In the above second optional embodiment, the higher the final jitter score value, the smaller the jitter during the translation of the OCT catheter, and the more stable the translation.

[0244] It should be understood that no matter what scoring rules are used, the scoring rules for the rotation score and the jitter score must be consistent, that is, when a higher rotation score represents a more stable rotation speed during the rotation of the OCT catheter, a higher jitter score must also represent smaller jitter during the translation of the OCT catheter (more stable translation); when a lower rotation score represents a more stable rotation speed during the rotation of the OCT catheter, a lower jitter score must also represent smaller jitter during the translation of the OCT catheter (more stable translation).

[0245] The same is true for other scores, which will not be listed here.

[0246] For example, the lower the jitter score, the smaller the jitter during the translation of the OCT catheter. Figure 7 The motion trajectory of the OCT catheter when it rotates one circle is shown in the figure. When the motion trajectory is within the area of ​​curve a, the calculated jitter score value belongs to the first level, which can be judged as no jitter; when the motion trajectory is between curve a and curve b, the calculated jitter score value belongs to the second level, which can be judged as slight jitter; when the motion trajectory is outside the curve b, the calculated jitter score value belongs to the third level, which can be judged as severe jitter. Figure 8 The offset displacement curve of the OCT catheter shown in FIG. 1 is a graph of the offset displacement when the catheter rotates one circle. When the offset displacement is within the area within curve c, the calculated jitter score value belongs to the first level, which can be judged as no jitter; when the offset displacement is between curve c and curve d, the calculated jitter score value belongs to the second level, which can be judged as slight jitter; when the offset displacement is outside curve d, the calculated jitter score value belongs to the third level, which can be judged as severe jitter.

[0247] Preferably, this embodiment S5 includes:

[0248] S51: Accumulating the rotation score value and the jitter score value to obtain a synchronization index value of the OCT catheter;

[0249] S52a: when the synchronization index value is within the first index threshold range, determining that the synchronization performance level of the OCT catheter is the fourth level;

[0250] S52b: when the synchronization index value is within the second index threshold range, determining that the synchronization performance level of the OCT catheter is the fifth level;

[0251] S52c: when the synchronization index value is not within the first index threshold range and the second index threshold range, determining that the synchronization performance level of the OCT catheter is the sixth level;

[0252] The synchronization performance of the OCT catheter represented by the fourth level, the fifth level and the sixth level decreases in sequence.

[0253] After the rotation score value and the jitter score value are obtained according to the above method, the accumulated value of the two is directly used as the synchronization index value, and the size of the value can be directly used to reflect the synchronization performance of the OCT catheter. The method is intuitive, effective, and easy to implement. In the process of using the size of the synchronization index value to reflect the synchronization performance of the OCT catheter, the value is compared with the two index threshold ranges to achieve a fine division of the synchronization performance level, which helps users to grade and screen the quality of OCT catheters, facilitate the screening of unqualified OCT catheters, and avoid images generated under abnormal conditions such as deformation, slippage, and jitter affecting clinical diagnosis.

[0254] Both the first index threshold range and the second index threshold range can be pre-set and adjusted according to actual conditions. For example, for the rotation score value and the jitter score value in the aforementioned optional embodiment, when the lower the rotation score value, the more stable the rotation speed of the OCT catheter during rotation, and the lower the jitter score value, the smaller the jitter during translation of the OCT catheter, the first index threshold range is taken as = 0, the second index threshold range is taken as = 1, and correspondingly, the fourth level is concretized as excellent, the fifth level is concretized as good, and the sixth level is concretized as poor. Then, when the obtained synchronization index value = 0, the synchronization performance level of the OCT catheter is determined to be excellent; when the obtained synchronization index value = 1, the synchronization performance level of the OCT catheter is determined to be good; when the obtained synchronization index value is greater than 1 (that is, not within the first index threshold range and the second index threshold range), the synchronization performance level of the OCT catheter is determined to be poor. Of course, the first index threshold range may be [0,1) and the second index threshold range may be [1,2). Then, when the obtained synchronization index value ∈ [0,1), the synchronization performance level of the OCT catheter is determined to be excellent; when the obtained synchronization index value ∈ [1,2), the synchronization performance level of the OCT catheter is determined to be good; when the obtained synchronization index value ≥ 2 (i.e., not within the first index threshold range and the second index threshold range), the synchronization performance level of the OCT catheter is determined to be poor.

[0255] For the rotation score value and jitter score value in the aforementioned optional embodiment, when the higher the rotation score value represents a more stable rotation speed during the rotation of the OCT catheter, and the higher the jitter score value represents a smaller jitter during the translation of the OCT catheter, the situation is the same as the above-mentioned situation that the lower the rotation score value represents a more stable rotation speed during the rotation of the OCT catheter, and the lower the jitter score value represents a smaller jitter during the translation of the OCT catheter, and will not be repeated here.

[0256] Embodiment 2

[0257] A system for detecting the rotational synchronization of an OCT catheter is applied to the method for detecting the rotational synchronization of an OCT catheter in the first embodiment, such as Fig. 9 As shown, the system comprises:

[0258] A feature extraction module, used to obtain a real-time catheter end surface image of the OCT catheter in the simulated blood vessel within a set time period, perform feature extraction on the real-time catheter end surface image, and obtain real-time coordinates of at least two feature points;

[0259] A feature matching module, used to perform feature point matching according to the real-time coordinates of at least two feature points to obtain a real-time rotation angle and a real-time offset displacement of the OCT catheter;

[0260] A rotation speed and displacement calculation module, used to calculate the instantaneous rotation speed of the OCT catheter according to the real-time rotation angle; and to calculate the cumulative offset displacement of the OCT catheter when it rotates one circle according to the real-time offset displacement;

[0261] A rotation and jitter evaluation module, used to obtain a device rotation speed corresponding to the motion controller, and obtain a rotation score value corresponding to the OCT catheter according to the instantaneous rotation speed and the device rotation speed; and obtain a jitter score value corresponding to the OCT catheter according to the real-time offset displacement and the cumulative offset displacement;

[0262] The synchronization evaluation module obtains the synchronization performance level of the OCT catheter according to the rotation score value and the jitter score value.

[0263] In this embodiment, the feature extraction module is first used to obtain a real-time catheter end face image, so that the real-time rotation angle and real-time offset displacement of the OCT catheter in the simulated blood vessel can be analyzed based on the real-time catheter end face image by using the feature matching module. The real-time rotation angle and real-time offset displacement obtained by the image analysis technology can more accurately reflect the actual movement of the OCT catheter. The real-time rotation angle can reflect the instantaneous rotation characteristics of the OCT catheter in the rotational movement, and then the speed and displacement calculation module can be used to calculate the instantaneous speed of the OCT catheter driven by the motion controller, so that the synchronization of the OCT catheter in the rotational movement can be analyzed according to the instantaneous speed. The real-time offset displacement can reflect the instantaneous translation characteristics of the OCT catheter in the translational movement, and based on the real-time offset displacement The rotation speed and displacement calculation module can also be used to calculate the cumulative offset displacement of the OCT catheter when it rotates one circle. The cumulative offset displacement reflects the translation characteristics of the OCT catheter when it rotates one circle. Therefore, by obtaining the real-time offset displacement and the cumulative offset displacement, it is convenient to subsequently comprehensively analyze the synchronization in the translation movement of the OCT catheter; using the rotation and jitter evaluation module, the synchronization of the OCT catheter rotation process is evaluated based on the instantaneous rotation speed and the acquired device rotation speed of the motion controller, and the corresponding rotation score value can be obtained, and the synchronization of the OCT catheter translation process is evaluated based on the real-time offset displacement and the cumulative offset displacement, and the corresponding jitter score value can be obtained; finally, the synchronization evaluation module is used to combine the two score values ​​to comprehensively evaluate the OCT catheter rotation synchronization, and the result is more comprehensive, accurate and reliable.

[0264] The OCT catheter rotation synchronization detection system of the present embodiment realizes accurate detection of synchronization and uniformity between the device end and the OCT catheter based on the real-time rotation angle and real-time offset displacement, rather than relying solely on the rotation speed detected by the built-in encoder of the motion controller. It can more accurately reflect the actual movement of the OCT catheter, and the detection results are more comprehensive, accurate and reliable. It can screen out unqualified OCT catheters and effectively avoid images generated under abnormal conditions such as deformation, slippage and shaking from affecting clinical diagnosis.

[0265] The functions of each module in the OCT catheter rotation synchronization detection system described in this embodiment are the same as the method steps of the OCT catheter rotation synchronization detection method described in Example 1. Therefore, for details not provided in this embodiment, please refer to Example 1 and Example 2. Figures 1 to 8 The detailed description will not be repeated here.

[0266] Embodiment 3

[0267] This embodiment provides another OCT catheter rotation synchronization detection system, such as Fig.10 As shown, including:

[0268] An image collector, used to collect real-time catheter end surface images of the OCT catheter in the simulated blood vessel within a set time period;

[0269] A processor is communicatively connected with the image collector and is used to receive the real-time catheter end surface image collected by the image collector; extract features from the real-time catheter end surface image to obtain real-time coordinates of at least two feature points; perform feature point matching according to the real-time coordinates of at least two feature points to obtain a real-time rotation angle and a real-time offset displacement of the OCT catheter; calculate the instantaneous rotation speed of the OCT catheter according to the real-time rotation angle; and calculate the cumulative offset displacement of the OCT catheter when it rotates one circle according to the real-time offset displacement;

[0270] A motion controller with a built-in encoder, which is in communication with the processor and is used to control the movement of the OCT catheter in the simulated blood vessel and detect the rotation speed of the device through the encoder;

[0271] The processor is further used to receive the device rotation speed detected by the encoder, and obtain a rotation score value corresponding to the OCT catheter based on the instantaneous rotation speed and the device rotation speed; and obtain a jitter score value corresponding to the OCT catheter based on the real-time offset displacement and the cumulative offset displacement; and obtain a synchronization performance level of the OCT catheter based on the rotation score value and the jitter score value.

[0272] In this embodiment, the image acquisition device and the motion controller with a built-in encoder are both connected to the processor for communication. The real-time catheter end face image acquired by the image acquisition device is transmitted to the processor, so that the processor can perform feature matching, rotation speed calculation, and offset displacement calculation. The simulated motion of the OCT catheter is controlled by the motion controller, and the detected device rotation speed is transmitted to the processor using its built-in encoder, so that the processor can perform rotation evaluation and jitter evaluation. The two evaluation results are combined to obtain the final synchronization performance level representing the synchronization of the OCT catheter.

[0273] The OCT catheter rotation synchronization detection system of the present embodiment realizes accurate detection of synchronization and uniformity between the device end and the OCT catheter based on the real-time rotation angle and real-time offset displacement, rather than relying solely on the rotation speed detected by the built-in encoder of the motion controller. It can more accurately reflect the actual movement of the OCT catheter, and the detection results are more comprehensive, accurate and reliable. It can screen out unqualified OCT catheters and effectively avoid images generated under abnormal conditions such as deformation, slippage and shaking from affecting clinical diagnosis.

[0274] The image acquisition device and the motion controller with built-in encoder can select suitable products or components according to the actual situation. These are common components in OCT catheter applications and the specific details will not be repeated here.

[0275] The functions implemented by the processor in this embodiment are the same as the method steps of the method for detecting the rotation synchronization of the OCT catheter described in Example 1, so the unfinished details of this embodiment are detailed in Example 1 and Figures 1 to 8 The detailed description will not be repeated here.

[0276] Embodiment 4

[0277] This embodiment also provides an OCT catheter rotation synchronization detection device, including a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the computer program implements the method steps in the OCT catheter rotation synchronization detection method of the first embodiment when executed.

[0278] Through a computer program stored in the memory and running on the processor, accurate detection of the synchronization and uniformity between the device end and the OCT catheter is achieved based on the real-time rotation angle and real-time offset displacement, rather than relying solely on the rotation speed detected by the built-in encoder of the motion controller. It can more accurately reflect the actual movement of the OCT catheter, and the detection results are more comprehensive, accurate and reliable. It can screen out unqualified OCT catheters and effectively avoid images generated under abnormal conditions such as deformation, slippage and jitter that affect clinical diagnosis.

[0279] The processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc. The processor is the control center of a computer device, and uses various interfaces and lines to connect various parts of the entire computer device.

[0280] The memory can be used to store computer programs and / or models. The processor realizes various functions of the computer device by running or executing the computer programs and / or models stored in the memory and calling the data stored in the memory. The memory can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system and at least one application required for a function (such as a sound playback function, an image playback function, etc.); the data storage area can store data created according to the use of the mobile phone (such as audio data, video data, etc.). In addition, the memory can include a high-speed random access memory and can also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart memory card (SmartMedia Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), at least one disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0281] It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of the processes and / or blocks in the flowchart and / or block diagram, can be implemented by a computer program. These computer programs can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0282] These computer programs may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory produce a manufactured product including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0283] These computer programs can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable device provide instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0284] This embodiment further provides a computer storage medium, which includes: at least one instruction, which implements the method steps in the method for detecting rotation synchronization of the OCT catheter in embodiment 1 when the instruction is executed by a computer.

[0285] By executing a computer storage medium containing at least one instruction, accurate detection of the synchronization and uniformity between the device end and the OCT catheter is achieved based on the real-time rotation angle and real-time offset displacement, rather than relying solely on the rotation speed detected by the built-in encoder of the motion controller. This can more accurately reflect the actual movement of the OCT catheter, and the detection results are more comprehensive, accurate, and reliable. Unqualified OCT catheters can be screened out, and images generated under abnormal conditions such as deformation, slippage, and shaking can be effectively avoided to affect clinical diagnosis.

[0286] Similarly, for details not yet included in this embodiment, see Embodiment 1, Embodiment 2, Embodiment 3 and Figures 1 to 10 The detailed description will not be repeated here.

[0287] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A method for detecting rotation synchronization of an OCT catheter, characterized in that: The OCT catheter is configured with a motion controller, and the method comprises: Acquire a real-time catheter end surface image of the OCT catheter in the simulated blood vessel within a set time period, perform feature extraction on the real-time catheter end surface image, and obtain real-time coordinates of at least two feature points; Performing feature point matching according to the real-time coordinates of at least two feature points to obtain a real-time rotation angle and a real-time offset displacement of the OCT catheter; According to the real-time rotation angle, the instantaneous rotation speed of the OCT catheter is calculated; according to the real-time offset displacement, the accumulated offset displacement of the OCT catheter when it rotates one circle is calculated; Obtaining a device rotation speed corresponding to the motion controller, and obtaining a rotation score value corresponding to the OCT catheter according to the instantaneous rotation speed and the device rotation speed; and obtaining a jitter score value corresponding to the OCT catheter according to the real-time offset displacement and the accumulated offset displacement; The synchronization performance level of the OCT catheter is obtained according to the rotation score value and the jitter score value.

2. The method for detecting rotation synchronization of an OCT catheter according to claim 1, characterized in that: The step of obtaining a rotation score value corresponding to the OCT catheter according to the instantaneous rotation speed and the device rotation speed includes: According to the instantaneous rotation speed, respectively calculating the instantaneous rotation speed mean square error and the average rotation speed of the OCT catheter within a set time period; Calculating the absolute value difference between the average rotation speed and the rotation speed of the device; It is determined whether the absolute difference in rotation speed satisfies a first preset criterion and whether the mean square error of the instantaneous rotation speed satisfies a second preset criterion, and the rotation score value corresponding to the OCT catheter is determined according to the satisfaction.

3. The method for detecting rotation synchronization of an OCT catheter according to claim 2, characterized in that: The rotation score value has a first initial score value; Determining the rotation score value corresponding to the OCT catheter according to the satisfied condition includes: When the absolute difference in rotation speed meets the first preset criterion, the first initial score value of the rotation score value is accumulated according to the first score value; otherwise, the first initial score value of the rotation score value is accumulated according to the second score value to obtain a first rotation score; When the instantaneous rotation speed mean square error satisfies the second preset criterion, the first initial score value of the rotation score value is accumulated according to the third score value; otherwise, the first initial score value of the rotation score value is accumulated according to the fourth score value to obtain a second rotation score; The rotation score value corresponding to the OCT catheter is obtained according to the first rotation score and the second rotation score.

4. The method for detecting rotation synchronization of an OCT catheter according to claim 2, characterized in that: The specific expression of the first preset criterion is: ; Wherein, R0 is the rotation speed of the equipment, is the average speed, r1 is the first preset threshold; And / or, the specific expression of the second preset criterion is: ; Among them, MSE R is the instantaneous speed mean square error, and r2 is the second preset threshold.

5. The method for detecting rotation synchronization of an OCT catheter according to claim 2, characterized in that: The method further comprises: Determining whether the absolute difference in rotation speed satisfies the first preset criterion; When the absolute difference in rotation speed does not satisfy the first preset criterion, determining that the OCT catheter is rotationally unstable; When the absolute difference in rotation speed satisfies the first preset criterion, it is determined whether the instantaneous rotation speed mean square error satisfies the second preset criterion. If so, it is determined that the OCT catheter rotation is stable; otherwise, it is determined that the OCT catheter rotation is unstable.

6. The method for detecting rotation synchronization of an OCT catheter according to claim 1, characterized in that: The real-time offset displacement includes the real-time lateral displacement and real-time longitudinal displacement of the OCT catheter in each frame within the set time period, and the cumulative offset displacement includes the cumulative lateral displacement and cumulative longitudinal displacement when the OCT catheter rotates one circle within the set time period; The step of obtaining a jitter score value corresponding to the OCT catheter according to the real-time offset displacement and the accumulated offset displacement includes: Obtaining a first jitter determination result according to the real-time lateral displacement and the real-time longitudinal displacement of all frames; Obtaining a second jitter determination result according to the accumulated lateral displacement and the accumulated longitudinal displacement; Obtaining a jitter result of the OCT catheter according to the first jitter determination result and the second jitter determination result; A jitter score value corresponding to the OCT catheter is determined according to the jitter result of the OCT catheter.

7. The method for detecting rotation synchronization of an OCT catheter according to claim 6, characterized in that: The obtaining a first jitter determination result according to the real-time lateral displacement and the real-time longitudinal displacement of all frames includes: Selecting any one frame of the real-time lateral displacement and the real-time longitudinal displacement, and determining whether the selected real-time lateral displacement and the selected real-time longitudinal displacement are both less than a first offset threshold; When the selected real-time lateral displacement and the real-time longitudinal displacement are both smaller than the first offset threshold, continue to judge whether the selected real-time lateral displacement and the real-time longitudinal displacement are both smaller than the second offset threshold; when the selected real-time lateral displacement and the real-time longitudinal displacement are both smaller than the second offset threshold, determine that the real-time jitter level of the OCT catheter at the selected frame is the first level; when at least one of the selected real-time lateral displacement and the real-time longitudinal displacement is not smaller than the second offset threshold, determine that the real-time jitter level of the OCT catheter at the selected frame is the second level; wherein the second offset threshold is smaller than the first offset threshold; When at least one of the selected real-time lateral displacement and the selected real-time longitudinal displacement is not less than the first offset threshold, determining that the real-time jitter level of the OCT catheter at the selected frame is a third level; According to the same method, determining the real-time jitter level of each frame of the OCT catheter; Determining the real-time jitter level with the highest priority among the real-time jitter levels of all frames of the OCT catheter as the first jitter determination result; The priorities of the first level, the second level and the third level increase in sequence, and the jitters represented by the first level, the second level and the third level increase in sequence.

8. The method for detecting rotation synchronization of an OCT catheter according to claim 7, characterized in that: The obtaining a second jitter determination result according to the accumulated lateral displacement and the accumulated longitudinal displacement includes: Determining whether the accumulated lateral displacement and the accumulated longitudinal displacement are both less than a third offset threshold; When the accumulated lateral displacement and the accumulated longitudinal displacement are both smaller than the third offset threshold, continue to judge whether the accumulated lateral displacement and the accumulated longitudinal displacement are both smaller than the fourth offset threshold; when the accumulated lateral displacement and the accumulated longitudinal displacement are both smaller than the fourth offset threshold, determine that the accumulated jitter level of the OCT catheter is the first level; when at least one of the accumulated lateral displacement and the accumulated longitudinal displacement is not smaller than the fourth offset threshold, determine that the accumulated jitter level of the OCT catheter is the second level; wherein the fourth offset threshold is smaller than the third offset threshold; When at least one of the accumulated lateral displacement and the accumulated longitudinal displacement is not less than the third offset threshold, determining that the accumulated jitter level of the OCT catheter is the third level; The accumulated jitter level of the OCT catheter is determined as the second jitter determination result.

9. The method for detecting rotation synchronization of an OCT catheter according to claim 8, characterized in that: The step of obtaining a jitter result of the OCT catheter according to the first jitter determination result and the second jitter determination result includes: The real-time jitter level or the accumulated jitter level with the highest priority among the first jitter determination result and the second jitter determination result is determined as the jitter result of the OCT catheter.

10. The method for detecting rotation synchronization of an OCT catheter according to claim 9, characterized in that: The jitter score value has a second initial score value; Determining a jitter score value corresponding to the OCT catheter according to the jitter result of the OCT catheter includes: When the jitter result of the OCT catheter is the first level, the second initial score value of the jitter score value is accumulated according to the fifth score value; when the jitter result of the OCT catheter is the second level, the second initial score value of the jitter score value is accumulated according to the sixth score value; when the jitter result of the OCT catheter is the third level, the second initial score value of the jitter score value is accumulated according to the seventh score value; The jitter score value corresponding to the OCT catheter is obtained according to the accumulated second initial score value.

11. The method for detecting rotation synchronization of an OCT catheter according to claim 1, characterized in that: The step of obtaining the synchronization performance level of the OCT catheter according to the rotation score value and the jitter score value includes: Accumulating the rotation score value and the jitter score value to obtain a synchronization index value of the OCT catheter; When the synchronization index value is within a first index threshold range, determining that the synchronization performance level of the OCT catheter is a fourth level; When the synchronization index value is within a second index threshold range, determining that the synchronization performance level of the OCT catheter is a fifth level; When the synchronization index value is not within the first index threshold range and the second index threshold range, determining that the synchronization performance level of the OCT catheter is the sixth level; The synchronization performance of the OCT catheter represented by the fourth level, the fifth level and the sixth level decreases in sequence.

12. The method for detecting rotation synchronization of an OCT catheter according to claim 1, characterized in that: The OCT catheter is equipped with an image collector, and the real-time rotation angle includes the rotation angle of each frame of the OCT catheter within the set time period; Calculating the instantaneous rotation speed of the OCT catheter according to the real-time rotation angle includes: According to the real-time rotation angle, a minimum number of frames for the OCT catheter to rotate one circle within the set time period is calculated; The time interval for the image collector to collect one frame of image is obtained in advance, and the instantaneous rotation speed of the OCT catheter is calculated according to the time interval and the minimum number of frames.

13. The method for detecting rotation synchronization of an OCT catheter according to claim 12, characterized in that: The specific formula for calculating the minimum number of frames is: ； Where n is the minimum number of frames, θ i is the rotation angle of the OCT catheter at the i-th frame within the set time period; The specific formula for calculating the instantaneous rotation speed is: ； Wherein, R is the instantaneous rotation speed, is the time interval.

14. The method for detecting rotation synchronization of an OCT catheter according to claim 1, characterized in that: The step of matching feature points according to the real-time coordinates of at least two feature points to obtain a real-time rotation angle and a real-time offset displacement of the OCT catheter includes: Selecting two target feature points from the at least two feature points, and constructing a transformation equation group according to the real-time coordinates of the two selected target feature points; The transformation equations are solved to obtain the real-time rotation angle and the real-time offset displacement of the OCT catheter.

15. The method for detecting rotation synchronization of an OCT catheter according to claim 14, characterized in that: Assume that the real-time coordinates of the two selected target feature points in the jth frame are (x 1j ,y 1j ) and (x 2j ,y 2j ), the real-time coordinates of the two selected target feature points in the j+1 frame are (x 1j+1 ,y 1j+1 ) and (x 2j+1 ,y 2j+1 ), then the transformation equations of the OCT catheter constructed between the jth frame and the j+1th frame are specifically: ； Among them, θ j is the real-time rotation angle of the OCT catheter at the jth frame, (t xj , t yj ) is the real-time offset displacement of the OCT catheter at the jth frame.

16. The method for detecting rotation synchronization of an OCT catheter according to any one of claims 1 to 15, characterized in that: The OCT catheter is equipped with an image collector; the two characteristic points are specifically the center of the catheter and the center of the marking point; The step of acquiring a real-time catheter end surface image of the OCT catheter in the simulated blood vessel within a set time period, and performing feature extraction on the real-time catheter end surface image to obtain real-time coordinates of at least two feature points includes: Using the image collector, collecting in real time an initial image of the OCT catheter in the simulated blood vessel within the set time period; Performing real-time foreground extraction on the initial image to obtain the real-time catheter end surface image; The real-time catheter end face image is subjected to binarization processing and connected domain detection in sequence to obtain a catheter binarization mask image and a marker point binarization mask image respectively; Performing contour extraction on the catheter binary mask image to obtain a catheter contour image; performing contour extraction on the marker point binary mask image to obtain a marker point contour image; The catheter contour image is fitted with a minimum radius enclosing circle to obtain the real-time coordinates corresponding to the center of the catheter circle; the marker point contour image is fitted with a minimum radius enclosing circle to obtain the real-time coordinates corresponding to the center of the marker point circle.

17. A system for detecting rotation synchronization of an OCT catheter, characterized in that: Applied to the method for detecting rotation synchronization of an OCT catheter as claimed in any one of claims 1 to 16, the system comprises: A feature extraction module, used to obtain a real-time catheter end surface image of the OCT catheter in the simulated blood vessel within a set time period, perform feature extraction on the real-time catheter end surface image, and obtain real-time coordinates of at least two feature points; A feature matching module, used to perform feature point matching according to the real-time coordinates of at least two feature points to obtain a real-time rotation angle and a real-time offset displacement of the OCT catheter; A rotation speed and displacement calculation module, used to calculate the instantaneous rotation speed of the OCT catheter according to the real-time rotation angle; and to calculate the cumulative offset displacement of the OCT catheter when it rotates one circle according to the real-time offset displacement; A rotation and jitter evaluation module, used to obtain a device rotation speed corresponding to the motion controller, and obtain a rotation score value corresponding to the OCT catheter according to the instantaneous rotation speed and the device rotation speed; and obtain a jitter score value corresponding to the OCT catheter according to the real-time offset displacement and the cumulative offset displacement; The synchronization evaluation module obtains the synchronization performance level of the OCT catheter according to the rotation score value and the jitter score value.

18. A system for detecting rotation synchronization of an OCT catheter, characterized in that: include: An image collector, used to collect real-time catheter end surface images of the OCT catheter in the simulated blood vessel within a set time period; A processor is communicatively connected with the image collector and is used to receive the real-time catheter end surface image collected by the image collector; extract features from the real-time catheter end surface image to obtain real-time coordinates of at least two feature points; perform feature point matching according to the real-time coordinates of at least two feature points to obtain a real-time rotation angle and a real-time offset displacement of the OCT catheter; calculate the instantaneous rotation speed of the OCT catheter according to the real-time rotation angle; and calculate the cumulative offset displacement of the OCT catheter when it rotates one circle according to the real-time offset displacement; A motion controller with a built-in encoder, which is in communication with the processor and is used to control the movement of the OCT catheter in the simulated blood vessel and detect the rotation speed of the device through the encoder; The processor is further configured to receive the device rotation speed detected by the encoder, and obtain a rotation score value corresponding to the OCT catheter according to the instantaneous rotation speed and the device rotation speed; A jitter score value corresponding to the OCT catheter is obtained according to the real-time offset displacement and the accumulated offset displacement; and a synchronization performance level of the OCT catheter is obtained according to the rotation score value and the jitter score value.

19. A device for detecting rotation synchronization of an OCT catheter, characterized in that: The method comprises a processor, a memory and a computer program stored in the memory and executable on the processor, wherein the computer program implements the method steps in the method for detecting rotation synchronization of an OCT catheter as claimed in any one of claims 1 to 16 when the computer program is executed.

20. A computer storage medium, characterized in that The computer storage medium comprises: at least one instruction, which implements the method steps in the method for detecting rotation synchronization of an OCT catheter as claimed in any one of claims 1 to 16 when the instruction is executed by a computer.

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