Control method and system for robot-assisted laser in-situ windowing

Abstract

The invention discloses a control method for robot-assisted laser in-situ windowing, which comprises the following steps: receiving an execution instruction sent by a main control end through a robot catheter system, sending a laser fiber into a target artery, and enabling the laser fiber to be in accurate contact with a stent covering film; a laser energy closed-loop control subsystem is combined to accurately ablate holes in a stent covering film through a photochemical effect and a photothermal effect, and laser windowing is achieved; in the laser windowing process, the thickness of the blood vessel wall is measured in real time based on optical coherence tomography, and the laser ablation process is detected based on photoacoustic monitoring, so that the laser power is dynamically adjusted, and it is ensured that the thermal damage range in the laser windowing process is smaller than 200 microns. Therefore, accurate creation of the channel between the aortic dissection false cavity and the true cavity is achieved, hemodynamic balance is recovered, the operation accuracy is improved, and the risk of complications in the perioperative period is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical assistance, and in particular relates to a control method and system for robot-assisted laser in situ fenestration. Background Art

[0002] Type A aortic dissection (Stanford A) is a rapidly progressive, acute aortic disease with a high mortality rate. Its pathological mechanism involves rupture of the aortic intima, leading to blood flow into the middle layer of the vessel wall, causing aortic delamination to form true and false lumens, which in turn affects the blood supply to important branch vessels and may even lead to serious complications such as aortic rupture, cardiac tamponade, or poor perfusion of vital organs. Traditionally, the treatment strategy for this lesion has been centered around open-chest surgery, including complex procedures such as total aortic arch replacement and elephant trunk stent implantation. However, for elderly patients with multiple comorbidities or those who cannot tolerate open-chest surgery, the high traumatic nature and high perioperative mortality of surgery have made minimally invasive interventional therapies a key focus of clinical research.

[0003] In recent years, endovascular aortic repair (EVAR) has been used in some cases. The method has shown good efficacy by implanting a covered stent to seal the dissection rupture and then deploying a bare stent distally to restore aortic blood flow. However, this approach has limited applicability in complex dissections involving supra-aortic branch vessels. If stent closure of the rupture leads to obstruction of blood supply to important branch vessels (such as the innominate artery, left common carotid artery, or left subclavian artery), the patient may suffer a severe stroke or distal ischemia. Therefore, to address this issue, laser in situ fenestration (LISF) has been proposed clinically. This involves the precise intravascular laser ablation of the stent membrane after stent deployment to create a controlled channel, thereby restoring blood supply to the branch vessels.

[0004] Laser in situ fenestration has gradually become an important supplement to endovascular treatment due to its highly minimally invasive characteristics, but it still faces many technical challenges. First, the accuracy of laser fenestration depends on the fine control of laser parameters, including power, pulse width, duty cycle and other factors. However, existing technologies are difficult to make real-time adaptive adjustments to the thickness of the vascular wall, tissue optical properties and thermal conduction effects of different patients, resulting in the risk of excessive or insufficient laser ablation in some cases. Secondly, the precise positioning and stability control of the catheter in the blood vessel are still the key to the success of the operation. Existing operations mainly rely on manual operation by doctors. In complex and tortuous vascular environments, the positioning accuracy of the laser catheter is affected by the hemodynamics in the aorta and the experience of the surgeon. It is difficult to ensure that every operation can achieve the ideal effect.

[0005] Traditional laser in situ fenestration still relies mainly on the doctor manually manipulating the catheter and laser. In difficult intravascular operations, manual operation is not only highly dependent on the surgeon's experience, but also makes it difficult to complete high-precision fenestration within the limited intervention time, resulting in complications such as window deviation and irregular morphology in some cases. The limitations of image navigation technology are also an important factor restricting surgical accuracy. The currently commonly used digital subtraction angiography (DSA) only provides two-dimensional fluoroscopic images and lacks real-time feedback on the structure of the vascular wall. The surgeon can only rely on experience to judge the position of the catheter in three-dimensional space and cannot perform precise spatial alignment. In addition, during the laser ablation process, the local temperature increase caused by the tissue absorbing heat may cause irreversible thermal damage. How to ensure effective fenestration while reducing the scope of thermal damage is an important problem facing current laser treatment technology. Summary of the Invention

[0006] The purpose of the present invention is to provide a control method for robot-assisted laser in situ fenestration, which adopts a robotic catheter system to replace traditional manual operation and combines multimodal image navigation to achieve submillimeter precision catheter control and target laser fenestration.

[0007] In order to solve the above problems, the technical solution of the present invention is: A control method for robot-assisted laser in-situ fenestration, comprising: The robotic catheter system receives execution instructions from the main control terminal and delivers the laser fiber into the target artery, ensuring precise contact between the laser fiber and the stent coating. Laser fiber precisely ablates holes in the stent coating through photochemical and photothermal effects, achieving laser fenestration. During the laser windowing process, the laser energy closed-loop control system measures the thickness of the blood vessel wall in real time based on optical coherence tomography, and detects the laser ablation progress based on photoacoustic monitoring to dynamically adjust the laser power to ensure that the thermal damage range of the laser windowing process is less than 200μm.

[0008] According to one embodiment of the present invention, the laser energy closed-loop control system predicts the heat-affected zone after laser action based on the following formula: Where ρ is tissue density, c is specific heat capacity, k is thermal conductivity, and Q is laser energy absorption term; Based on the heat-affected zone, the following power adjustment strategy is adopted to ensure that the thermal damage range during the laser windowing process is less than 200μm: Where Plaser(t) is the real-time output power of the laser, P0 is the initial power, α is the tissue absorption coefficient, and d(t) is the real-time measured distance between the optical fiber and the blood vessel wall.

[0009] According to an embodiment of the present application, the robot catheter system realizes flexible adjustment of the catheter in the process of sending the laser fiber into the target artery based on the following dynamic characteristics: Wherein, q is the joint angle vector of the catheter, M(q) is the inertia matrix, C(q, q˙) is the Coriolis matrix, G(q) is the gravity matrix, and τ is the external control input.

[0010] According to an embodiment of the present application, the following adaptive impedance control strategy is adopted when the catheter enters the blood vessel or approaches the blood vessel wall, so as to reduce the mechanical damage to the blood vessel wall: Wherein, K p is the stiffness matrix, D is the damping matrix, x is the current pose of the catheter, x d is the target pose, and are the current speed and the expected speed, respectively.

[0011] According to an embodiment of the present application, the robot catheter system for sending the laser fiber into the target artery further comprises: Augmented reality image fusion is adopted to integrate DSA, IVUS and OCT images, so as to realize three-dimensional blood vessel reconstruction and intraoperative navigation.

[0012] According to an embodiment of the present application, in the process of integrating DSA, IVUS and OCT images, mutual information optimization algorithm is adopted to realize image registration; and the optimization objective function is: Wherein, I1 and I2 are DSA and OCT images respectively, T is a spatial transformation matrix, and p is a joint probability distribution.

[0013] According to an embodiment of the present application, during the execution of the robot catheter system, the catheter end is equipped with a fiber Bragg grating sensor to monitor the contact force with the blood vessel wall in real time; when the contact force exceeds the set threshold, the catheter motion parameters are automatically adjusted to prevent damage to the blood vessel wall.

[0014] According to an embodiment of the present application, the laser energy closed-loop control system monitors the temperature distribution of the operation area in real time through infrared thermal imaging during the laser windowing process; when the temperature exceeds the safety threshold, the laser power is automatically reduced or the laser emission is suspended to prevent excessive thermal damage.

[0015] According to an embodiment of the present application, when the catheter motion is abnormal or the image navigation deviates, an emergency stop mechanism is triggered within a preset time to ensure safety.

[0016] A control system of a robot-assisted laser in-situ fenestration, comprising: A robot catheter subsystem configured to receive an execution instruction sent by a master control end, send a laser fiber into a target artery, and make the laser fiber precisely contact a stent graft; A laser energy closed-loop control subsystem configured to precisely ablate a hole on the stent graft through photochemical effect and photothermal effect, and realize laser fenestration; during the laser fenestration, based on optical coherence tomography, measure a blood vessel wall thickness in real time, and based on photoacoustic monitoring, detect a laser ablation process, so as to dynamically adjust a laser power and ensure that a thermal damage range of the laser fenestration process is less than 200 mu m; A multi-modal image navigation subsystem configured to, during catheter positioning and laser fenestration, adopt augmented reality image fusion, integrate DSA, IVUS and OCT images, realize three-dimensional blood vessel reconstruction and intraoperative navigation.

[0017] Compared with the prior art, the robot-assisted laser in-situ fenestration control method has the following advantages and positive effects: The robot-assisted laser in-situ fenestration control method in the embodiment of the present application receives an execution instruction sent by a master control end through a robot catheter system, sends a laser fiber into a target artery, and makes the laser fiber precisely contact a stent graft; in combination with a laser energy closed-loop control subsystem, a hole is precisely ablated on the stent graft through photochemical effect and photothermal effect, and laser fenestration is realized; during the laser fenestration, based on optical coherence tomography, a blood vessel wall thickness is measured in real time, and based on photoacoustic monitoring, a laser ablation process is detected, so as to dynamically adjust a laser power and ensure that a thermal damage range of the laser fenestration process is less than 200 mu m. Thus, a channel between an aortic dissection false lumen and a true lumen is precisely created, blood flow hemodynamic balance is restored, surgical precision is improved, and perioperative complication risk is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 A robot-assisted laser in-situ fenestration control method flowchart in the embodiment of the present application; Figure 2 A robot catheter system control flowchart in the embodiment of the present application; Figure 3 A laser energy closed-loop control system control flowchart in the embodiment of the present application; Figure 4 A surgical step schematic diagram in the embodiment of the present application. DETAILED DESCRIPTION

[0019] The control method and system of robot-assisted laser in-situ fenestration are further described in detail below in combination with the accompanying drawings and specific embodiments. The advantages and features of the present application will be clearer according to the following description and claims.

[0020] The control method and system of robot-assisted laser in-situ fenestration provided in the embodiment can precisely control the laser catheter through a high-degree-of-freedom catheter robot, overcome the stability and precision limitations of traditional manual operation, and combine multi-modal medical image navigation, intelligent feedback regulation and control, and adaptive laser energy management to ensure real-time controllability and precise execution of the fenestration process.

[0021] The control method of robot-assisted laser in-situ fenestration provided in the embodiment comprises the following steps: The robot catheter system receives the execution instruction sent by the master control end, sends the laser optical fiber into the target artery, and makes the laser optical fiber precisely contact the stent covering film; The laser optical fiber precisely ablates holes on the stent covering film through photochemical and photothermal effects, and realizes laser fenestration; During the laser fenestration process, the laser energy closed-loop control system measures the blood vessel wall thickness in real time based on optical coherence tomography, and detects the laser ablation process based on photoacoustic monitoring, so as to dynamically adjust the laser power and ensure that the thermal damage range of the laser fenestration process is less than 200 μm.

[0022] Specifically, the embodiment relates to a high-degree-of-freedom robot catheter system specially designed for minimally invasive treatment of type A aortic dissection. The system is composed of multiple independently controllable joint units, each of which is driven by a servo motor to realize the axial advancement, rotation and bending movement of the catheter. The catheter tip integrates a laser optical fiber and an optical coherence tomography (OCT) probe to realize precise laser fenestration operation and real-time imaging.

[0023] Please refer to Figure 1 In terms of control, a master-slave control architecture is adopted, and the doctor inputs instructions through the master operation end, and the catheter robot executes corresponding actions as the slave end. The dynamic characteristics of the robot catheter can be described by the following nonlinear equation: Where q is the joint angle vector of the catheter, M(q) is the inertia matrix, C(q, q˙) is the Coriolis matrix, G(q) is the gravity matrix, and τ is the external control input.

[0024] This equation describes the dynamic behavior of the catheter in the blood vessel environment, so that the system can adjust the compliance of the catheter through intelligent impedance regulation (Impedance Control) to adapt to the elastic properties of the blood vessels of different patients.

[0025] To improve the accuracy and safety of the operation, the system introduces an adaptive impedance control strategy. The control equation is: Where F is the force applied at the catheter tip, K p is the position stiffness coefficient, D is the damping coefficient, x and x d are the current pose and desired pose, and are the current speed and desired speed. By adjusting the values of K p and D in real time, the system can adapt to different vascular environments, ensuring the stability and flexibility of the catheter in complex vascular paths; automatically adjust the compliance when close to the blood vessel wall to reduce mechanical damage to the blood vessel wall.

[0026] The laser energy closed-loop control system in this embodiment is a laser energy closed-loop control system based on real-time OCT imaging, which is used to accurately control the ablation process of laser on the blood vessel wall. The system obtains the thickness information of the blood vessel wall through OCT, and combines photoacoustic imaging (PAI) to monitor the progress of laser ablation.

[0027] During laser ablation, the heat conduction of the tissue can be described by the following equation: Where ρ is the tissue density, c is the specific heat capacity, k is the thermal conductivity, and Q is the laser energy absorption rate. Based on this equation, the system uses finite element analysis (FEA) to simulate the temperature distribution under the action of laser and predict the range of heat affected zone (HAZ).

[0028] To ensure the safety of the ablation process, the system dynamically adjusts the laser parameters such as power, pulse width and duty cycle according to the blood vessel wall thickness measured by OCT and the ablation depth feedback by PAI. Specifically, the laser power adjustment strategy is: Where Plaser(t) is the real-time output power of the laser, P0 is the initial power, α is the tissue absorption coefficient, and d(t) is the real-time measured distance between the optical fiber and the blood vessel wall.

[0029] Through the above control strategy, the system can accurately control the depth and range of laser ablation, and avoid excessive thermal damage to the surrounding healthy tissue.

[0030] To ensure the accuracy of catheter positioning and laser windowing, this embodiment also adopts an augmented reality (AR) navigation system that integrates multiple medical images, as well as a corresponding safety protection mechanism. The system integrates multiple image data such as digital subtraction angiography (DSA), intravascular ultrasound (IVUS) and OCT, constructs a three-dimensional blood vessel model, and provides an intuitive surgical navigation interface for doctors.

[0031] In the image fusion process, a mutual information optimization algorithm is used for registration, and the objective function is: where I1 and I2 are the DSA and OCT images, T is the spatial transformation matrix, and p is the joint probability distribution. By optimizing this objective function, the system achieves high-precision image registration, ensuring spatial consistency between different modal images.

[0032] In addition, to ensure the safety of the surgical process, the embodiment also adopts a multi-layer protection mechanism, including: 1. Real-time force feedback: The catheter tip is equipped with a fiber Bragg grating (FBG) sensor that monitors the contact force with the vessel wall in real time. When the contact force exceeds a set threshold (such as 0.1N), the system automatically adjusts the catheter motion parameters to prevent damage to the vessel wall.

[0033] 2. Temperature monitoring: The temperature distribution of the surgical area is monitored in real time through infrared thermal imaging. When the temperature exceeds a safety threshold (such as 42°C), the system automatically reduces the laser power or suspends laser emission to prevent excessive heat damage.

[0034] 3. Dual-redundant emergency stop mechanism: The system is equipped with two independent emergency stop devices, electromagnetic locking and mechanical braking. When abnormal conditions are detected, such as abnormal catheter movement or image navigation deviation, the system triggers the emergency stop mechanism within 50 milliseconds to ensure surgical safety.

[0035] Through the above implementation, precise minimally invasive treatment of type A aortic dissection can be assisted, significantly improving the safety and effectiveness of the operation.

[0036] Based on the same concept, the embodiment also provides a control system for robot-assisted laser in-situ fenestration, comprising: A robotic catheter subsystem configured to receive execution instructions sent by the master control end, send the laser fiber into the target artery, and make the laser fiber precisely contact the stent graft; A laser energy closed-loop control subsystem configured to precisely ablate holes on the stent graft through photochemical and photothermal effects, and realize laser fenestration; during the laser fenestration process, based on optical coherence tomography, the blood vessel wall thickness is measured in real time, and the laser ablation process is detected based on photoacoustic monitoring, to dynamically adjust the laser power, ensuring that the thermal damage range during the laser fenestration process is less than 200μm; A multi-modal image navigation subsystem configured to use augmented reality image fusion to integrate DSA, IVUS, and OCT images during catheter positioning and laser fenestration, and realize three-dimensional vessel reconstruction and intraoperative navigation.

[0037] The above subsystems realize real-time data transmission and control through CAN bus.

[0038] Specifically, the hardware structure and specifications of the robotic catheter subsystem of this embodiment are as follows: Robotic catheter: Made of Shape Memory Alloy (SMA) nickel-titanium alloy, it has a distal flexible unit with an outer diameter of 3.2mm and can be bent ±180°. The catheter is 120cm long and has three degrees of freedom (propulsion / rotation / bending).

[0039] Servo drive system: Maxon EC-45 brushless DC servo motor is used, coupled with a high-precision encoder (10,000PPR) to ensure the advancement and rotation accuracy of the catheter reaches 0.1mm and 0.2°.

[0040] Force feedback sensor: A fiber Bragg grating (FBG) sensor is integrated at the end of the catheter with a measurement range of 0-2N and a resolution of 0.01N. It is used to monitor the catheter contact force in real time to prevent vascular damage.

[0041] Electromagnetic navigation system: Adopts NDI Aurora® electromagnetic positioning system with a positioning accuracy of 0.5mm, combined with CTA / DSA images to provide high-precision catheter position information.

[0042] The control strategy of this subsystem can be found in Figure 2 , its motion control model: Based on the nonlinear dynamic characteristics of the catheter, the system adopts adaptive impedance control (Adaptive Impedance Control). The control equation is as follows: Where F is the force applied by the end of the catheter, K p is the position stiffness coefficient, D is the damping coefficient, x and x d are the current pose and the desired pose respectively, and The system uses fuzzy logic to adaptively adjust impedance parameters, reducing stiffness in curved areas of the vessel to ensure compliance, while also increasing damping to avoid unnecessary vibration when the catheter is advanced to the target fenestration area.

[0043] The laser energy closed-loop control subsystem in this embodiment uses a 1470nm semiconductor laser (Lumenis AcuPulse™ Surgical Laser), whose pulse mode is suitable for high-precision tissue ablation. The laser is transmitted to the end of the catheter through a high-transmittance silicon optical fiber (inner diameter 200μm, outer diameter 400μm), achieving precise laser release. For its control strategy, please refer to Figure 3 .

[0044] (1) Laser parameters • Output power: 5-20 W (adjustable) • Pulse width: 1-100 ms (adjustable) • Duty cycle: 10%-30% (2) Closed-loop energy regulation mechanism • OCT real-time feedback: St. Jude Ilumien™ OCT imaging system is used, with a scanning rate of 100 frames / second, measuring vessel wall thickness in the range of 50-800 μm, for accurate setting of laser ablation parameters.

[0045] • Laser energy control equation: where Plaser(t) is the real-time output power of the laser, P0 is the initial power, α is the tissue absorption coefficient, and d(t) is the real-time measured distance between the optical fiber and the vessel wall.

[0046] By combining OCT scanning data with photoacoustic monitoring (PAI), the system can achieve dynamic power regulation, with a heat-affected zone (HAZ) of less than 200 μm, avoiding damage to adjacent tissues.

[0047] The multimodal image navigation subsystem of this embodiment uses multimodal image fusion augmented reality (AR) navigation, combining CTA, DSA, and IVUS data to construct a high-precision three-dimensional vascular anatomical model.

[0048] Image fusion: Based on the Mutual Information Optimization algorithm, OCT / IVUS / DSA registration is achieved to ensure spatial consistency, with the optimization objective function as follows: where I1 and I2 are DSA and OCT images, respectively, T is the spatial transformation matrix, and p is the joint probability distribution. Through this optimization strategy, the system can control the catheter navigation error within 0.5 mm.

[0049] In addition, to ensure the safety of the surgical process, this embodiment also adopts a multi-layer protection mechanism, including: Real-time force feedback: If the fiber Bragg grating (FBG) detects that the catheter contact force exceeds 0.1 N, the system immediately adjusts the impedance parameters and triggers a visual alarm.

[0050] Temperature monitoring: Infrared thermal imaging (FLIR One Pro) is used, with a measurement range of 30-45°C and an accuracy of ±0.5°C. When the temperature of the windowed area exceeds 42°C, the system automatically reduces the laser power.

[0051] Dual-redundant emergency stop mechanism: including electromagnetic locking and mechanical braking, when detecting abnormal motion of catheter or image registration error exceeding 1mm, the system will trigger emergency stop within 50ms to prevent misoperation.

[0052] Application example Based on the above control method and system of robot-assisted laser in-situ fenestration, an application example is introduced as follows: Patient information: male, 62 years old; disease: Stanford type A aortic dissection, dissection involving aortic arch, left subclavian artery involved.

[0053] Please refer to Figure 4 for the operation steps. 1. Preoperative planning: CTA image reconstruction of patient's three-dimensional vascular model, determination of fenestration target point, target position is 15±3mm away from the opening of left subclavian artery.

[0054] 2. Catheter navigation: robot catheter through right femoral artery approach, under the guidance of electromagnetic positioning and AR navigation, advance to the aortic arch dissection position along the preset path.

[0055] 3. Force feedback fine tuning: the system adjusts the catheter stiffness through impedance-admittance control to ensure that the laser fiber maintains appropriate contact force (<0.1N) with the vessel wall.

[0056] 4. Laser fenestration: based on OCT measurement of vessel wall thickness (560μm), the system automatically adjusts the laser power to 12W, pulse width 80ms, pulse mode, and completes the creation of a 4mm diameter window.

[0057] 5. Postoperative evaluation: IVUS confirms that the fenestration is unobstructed, blood flow is restored, and the target blood flow velocity difference is less than 15cm / s, ensuring postoperative hemodynamic balance.

[0058] Postoperative follow-up: the patient recovered well after the operation, CTA review 7 days after the operation showed that the fenestration area was unobstructed, there was no aneurysmal dilatation of the vessel wall, and there were no complications.

[0059] 6. Expected technical indicators Catheter navigation error ≤0.5mm; Laser fenestration positioning error ≤0.8mm; Postoperative blood flow recovery flow velocity difference <15cm / s; Heat damage range (HAZ) ≤200μm; Postoperative complication rate <5%; Intraoperative emergency stop response time <50ms; Fenestration diameter control accuracy ±0.2mm.

[0060] The embodiments of the present application are explained in detail above with reference to the drawings, but the present application is not limited to the above-described embodiments. Even if various changes are made to the present application, if the changes fall within the scope of the claims of the present application and equivalents thereof, they are still within the protective scope of the present application.

Claims

1. A control method for robot-assisted laser in situ fenestration, characterized in that: include: The robotic catheter system receives execution instructions from the main control terminal and delivers the laser fiber into the target artery, ensuring precise contact between the laser fiber and the stent coating. Laser fiber precisely ablates holes in the stent coating through photochemical and photothermal effects, achieving laser fenestration. During the laser windowing process, the laser energy closed-loop control system measures the thickness of the blood vessel wall in real time based on optical coherence tomography, and detects the laser ablation progress based on photoacoustic monitoring to dynamically adjust the laser power to ensure that the thermal damage range of the laser windowing process is less than 200μm.

2. The control method of robot-assisted laser in situ fenestration according to claim 1, characterized in that: The laser energy closed-loop control system predicts the heat-affected zone after laser action based on the following formula: Where ρ is tissue density, c is specific heat capacity, k is thermal conductivity, and Q is laser energy absorption term; Based on the heat-affected zone, the following power adjustment strategy is adopted to ensure that the thermal damage range during the laser windowing process is less than 200μm: Among them, P laser (t) is the real-time output power of the laser, P0 is the initial power, α is the tissue absorption coefficient, and d(t) is the real-time measured distance between the optical fiber and the blood vessel wall.

3. The control method of robot-assisted laser in situ fenestration according to claim 1, characterized in that: The robotic catheter system achieves flexibility adjustment of the catheter based on the following dynamic characteristics during the process of delivering the laser optical fiber into the target artery: Where q is the joint angle vector of the catheter, M(q) is the inertia matrix, C(q,q˙) is the Coriolis matrix, G(q) is the gravity matrix, and τ is the external control input.

4. The control method of robot-assisted laser in situ fenestration according to claim 1 or 3, characterized in that: After the catheter enters the blood vessel or approaches the blood vessel wall, the following adaptive impedance control strategy is used to reduce mechanical damage to the blood vessel wall: Among them, K p is the stiffness matrix, D is the damping matrix, x is the current position of the catheter, x d is the target pose, and are the current speed and the expected speed respectively.

5. The control method of robot-assisted laser in situ fenestration according to claim 1, characterized in that: The robotic catheter system further comprises: Augmented reality image fusion is used to integrate DSA, IVUS, and OCT images to achieve three-dimensional vascular reconstruction and intraoperative navigation.

6. The control method of robot-assisted laser in situ fenestration according to claim 5, characterized in that: In the process of integrating DSA, IVUS, and OCT images, the mutual information optimization algorithm is used to achieve image registration; its optimization objective function is: Where I1 and I2 are DSA and OCT images respectively, T is the spatial transformation matrix, and p is the joint probability distribution.

7. The control method of robot-assisted laser in situ fenestration according to claim 1, characterized in that: During the execution of the robotic catheter system, the end of the catheter is equipped with a fiber Bragg grating sensor to monitor the contact force with the blood vessel wall in real time; when the contact force exceeds the set threshold, the catheter movement parameters are automatically adjusted to prevent damage to the blood vessel wall.

8. The control method of robot-assisted laser in situ fenestration according to claim 1, characterized in that: During the laser windowing process, the laser energy closed-loop control system monitors the temperature distribution in the surgical area in real time through infrared thermal imaging; when the temperature exceeds the safety threshold, it automatically reduces the laser power or pauses the laser emission to prevent excessive thermal damage.

9. The control method of robot-assisted laser in situ fenestration according to claim 1, characterized in that: When the catheter moves abnormally or the image navigation deviates, the emergency stop mechanism is triggered within the preset time to ensure safety.

10. A control system for robot-assisted laser in situ fenestration, characterized in that: include: The robotic catheter subsystem is configured to receive execution instructions sent by the main control terminal, deliver the laser fiber into the target artery, and make the laser fiber contact the stent coating precisely; The laser energy closed-loop control subsystem is configured to precisely ablate holes in the stent coating through photochemical and photothermal effects, achieving laser fenestration. During the laser fenestration process, optical coherence tomography is used to measure vessel wall thickness in real time, and photoacoustic monitoring is used to monitor the laser ablation progress. This allows for dynamic adjustment of laser power to ensure that the thermal damage range during the laser fenestration process is less than 200μm. The multimodal imaging navigation subsystem is configured to use augmented reality image fusion to integrate DSA, IVUS, and OCT images during catheter positioning and laser fenestration to achieve three-dimensional vascular reconstruction and intraoperative navigation.

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