Laser treatment balloon catheter and laser treatment instrument

Abstract

The application discloses a laser treatment balloon catheter and a laser treatment instrument. The laser treatment balloon catheter comprises a catheter piece, a balloon, an optical fiber and a control handle. The catheter piece comprises an inner tube part and an outer tube part which are arranged in a nested mode. The distal end of the inner tube part extends beyond the distal end of the outer tube part. A liquid inlet cavity is formed between the inner tube part and the outer tube part. An optical fiber channel through which the optical fiber passes is arranged in the inner tube part. The balloon is arranged at the distal end of the catheter piece and is arranged outside the tube segment of the inner tube part extending out of the outer tube part. The two ends of the balloon are in sealing connection with the distal ends of the inner tube part and the outer tube part. The control handle comprises a handle seat and a control assembly. A liquid inlet opening which is communicated to the liquid inlet cavity and is used for introducing an expansion medium into the balloon is arranged on the handle seat. The proximal end of the optical fiber is slidably connected to the handle seat and can slide in the optical fiber channel under the control of the control assembly. The laser treatment balloon catheter can realize the fixed-point expansion of the inner diameter of a blood vessel and avoid the contact between the optical fiber and the diseased tissue on the inner wall of the blood vessel during the pushing process.

Description

Technical Field

[0001] This application relates to the field of medical devices utilizing optical fibers, and particularly to a laser therapy balloon catheter and laser therapy device. Background Technology

[0002] Laser ablation technology, with its advantages of minimal invasiveness, rapid recovery, and definite efficacy, has been widely used in the minimally invasive treatment of peripheral vascular arteriosclerosis obliterans and coronary artery stenosis. Clinically used laser ablation devices generally consist of a laser as the energy output device and a corresponding catheter assembly. The catheter assembly includes a catheter element and an optical fiber for transmitting laser energy to the target site. The inner lumen of the catheter element forms an optical fiber channel through which the optical fiber passes, and the distal end of the catheter element has an appropriate form of contrast-enhancing structure. During use, after establishing a delivery channel through a guidewire, the catheter assembly is pushed along the guidewire to the lesion site, allowing the optical fiber to reach the same location.

[0003] While existing laser therapy catheters can meet basic clinical treatment needs, they still have the following technical limitations: Typically, to ensure the optical fiber reaches the lesion site along with the catheter assembly, a fixed connection is required between the catheter assembly and the laser optical fiber. During advancement, when passing through narrow blood vessels or lesion sites, the catheter assembly may be unable to pass due to limited internal space or partial obstruction of the vessel's interior by the lesion. In such cases, continuing to advance the catheter assembly along the guidewire can easily lead to the optical fiber at the tip of the assembly puncturing the vessel wall or the lesion, resulting in adverse consequences. Summary of the Invention

[0004] This application provides a laser therapy balloon catheter and a laser therapy device, which can achieve targeted expansion of the blood vessel diameter while avoiding contact between the optical fiber and the blood vessel or lesions on the blood vessel wall during the pushing process, thereby improving the pushing performance of the laser therapy balloon catheter.

[0005] According to a first aspect of this application, a laser therapy balloon catheter is provided, the laser therapy balloon catheter comprising a catheter element, a balloon, an optical fiber, and a control handle, wherein: The conduit includes an inner tube and an outer tube nested together. The distal end of the inner tube extends beyond the distal end of the outer tube. A liquid inlet cavity is formed between the inner tube and the outer tube. An optical fiber channel for the optical fiber to pass through is provided inside the inner tube. The balloon is disposed at the distal end of the catheter and sleeved on the outside of the section of the inner tube that extends out of the outer tube. The two ends of the balloon are sealed and connected to the distal ends of the inner tube and the outer tube. The control handle includes a handle base and a control component. The handle base is provided with a liquid inlet that communicates with the liquid inlet chamber to introduce an expansion medium into the balloon. The proximal end of the optical fiber is slidably connected to the handle base and can be controlled by the control component to slide within the optical fiber channel.

[0006] In some embodiments, the catheter is slidably connected to the handle seat; the control assembly includes an optical fiber control element for controlling the sliding of the optical fiber, and a catheter control element for controlling the sliding of the catheter.

[0007] In some embodiments, the proximal end of the optical fiber protrudes from the optical fiber channel within the handle seat, and the optical fiber control element is configured as an optical fiber guide wheel capable of rolling relative to the handle seat, with a portion of the guide wheel extending through the seat of the handle seat to a position inside the handle seat capable of positive pressure contact with the optical fiber.

[0008] In some embodiments, the catheter assembly further includes a control rod portion configured as a solid rod body, the control rod portion being coaxially connected to the proximal ends of the inner tube portion and the outer tube portion, and the catheter assembly sliding relative to the handle seat through the cooperation of the control rod portion with the catheter control component.

[0009] In some embodiments, the catheter control element is configured as a catheter guide wheel that can roll relative to the handle seat, with a portion of the guide wheel extending through the seat of the handle seat to a position inside the handle seat that can positively contact the control lever portion.

[0010] In some embodiments, the inner tube portion, the outer tube portion, and the control rod portion are integrally formed.

[0011] In some embodiments, the catheter is integrally formed with the balloon.

[0012] In some embodiments, the inner diameter of the distal section of the inner tube is adapted to the diameter of the optical fiber, so that the optical fiber can be centrally positioned within the conduit.

[0013] In some embodiments, a very fine thermocouple is provided on the inner side of the distal end of the balloon.

[0014] According to a second aspect of this application, a laser therapy device is also provided, the laser therapy device including a laser and the laser therapy balloon catheter of any of the foregoing embodiments.

[0015] The technical solutions provided by the embodiments of this application may include the following beneficial effects: It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of a laser therapy balloon catheter according to an embodiment of this application. In the figure, the optical fiber is retracted inside the balloon. Figure 2 This is a schematic diagram of the structure of a laser therapy balloon catheter according to another embodiment of this application, compared to... Figure 1 The optical fiber in the diagram extends to the outside of the distal end of the balloon. Figure 3 yes Figure 1 A schematic diagram of the structure shown in the image after the balloon has been inflated. Figure 4 yes Figure 3 The diagram shows an optical fiber extending beyond the distal end of the inflated balloon.

[0017] Explanation of reference numerals in the attached figures 1. Catheter fittings; 11. Inner tube section; 111. Fiber optic channel; 12. Outer tube section; 13. Inlet chamber; 14. Control lever section; 2. Balloon; 3. Fiber optic cable; 4. Control handle; 41. Handle seat; 411. Seat body; 412. Inlet tube section; 4121. Inlet port; 42. Control components; 421. Fiber optic guide wheel; 422. Catheter guide wheel. Detailed Implementation

[0018] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. In the following description, when referring to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The modes described in the following exemplary embodiments do not represent all modes consistent with this application, but are merely preferred embodiments of this application. Those skilled in the art can make some modifications or alterations to the disclosed technical content to create equivalent embodiments without departing from the scope of the technical solution of this application. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application, without departing from the content of the technical solution of this application, shall still fall within the scope of the technical solution of this application.

[0019] Furthermore, in the description of this application, "proximal end" and "distal end" are defined with reference to the operator's position when the product is in use: the distal end refers to the end of the instrument or component that is relatively far from the operator, and the proximal end refers to the end of the instrument or component that is relatively close to the operator. Referring to the orientation shown in the various figures of this application, the left end is considered the proximal end and the right end the distal end. The embodiments of this application will now be described in detail with reference to the accompanying figures.

[0020] When using lasers to ablate target tissue within blood vessels, the laser treatment catheter needs to be inserted into the lesion in the designated blood vessel along the approach established by the guidewire, and ablation is achieved using the photothermal effect of the laser. Unlike the interventional stent procedure used for vascular dilation, laser treatment involves ablation at a specific location using an optical fiber, and the diameter of the optical fiber itself is not large. Therefore, the design considerations for this type of catheter typically focus on ensuring laser beam transmission and avoiding thermal damage to the blood vessel.

[0021] However, due to the lesion's size within the designated blood vessel and the vessel's small diameter, the fiber optic cable can easily puncture the vessel wall or lesion tissue during catheter insertion. Furthermore, when the lesion is too large, the distal end of the catheter may not even reach the designated location, making endovascular ablation impossible. This application addresses these issues by specifically resolving the problem of distal catheter accessibility.

[0022] The embodiments of this application will now be described in detail with reference to the accompanying drawings. Unless otherwise specified, the features in the following embodiments can be combined with each other.

[0023] like Figure 1 As shown, a laser therapy balloon catheter according to an embodiment of this application includes a catheter component 1, a balloon 2, an optical fiber 3, and a control handle 4. The catheter component 1 includes an inner tube portion 11 and an outer tube portion 12. The inner tube portion 11 and the outer tube portion 12 are nested together to form a fluid inlet chamber 13 between them. The fluid inlet port 4121, mentioned later, located on the control handle 4, communicates with this fluid inlet chamber 13.

[0024] The distal end of the inner tube 11 extends beyond the distal end of the outer tube 12. The balloon 2 is positioned at the distal end of the catheter component 1 and sleeved on the outside of the section of the inner tube 11 extending beyond the outer tube 12. Both ends of the balloon 2 are sealed to the distal ends of the inner tube 11 and the outer tube 12. In this way, the inner cavity of the balloon 2 communicates with the inlet chamber 13, allowing the expansion medium entering the inlet chamber 13 through the inlet port 4121 to flow into the balloon 2 and inflate it.

[0025] The inner tube 11 is provided with an optical fiber channel 111 through which the optical fiber 3 passes. The control handle 4 includes a handle base 41 and a control component 42. The proximal end of the optical fiber 3 is slidably connected to the handle base 41 and can be controlled by the control component 42 to slide within the optical fiber channel 111.

[0026] exist Figure 1 Based on the combination Figure 2 As shown, Figure 1 The state shown is such that the optical fiber 3 is completely housed within the optical fiber channel 111, with its distal end not protruding from the catheter element 1. In this state, pushing the laser therapy balloon catheter forward can prevent the optical fiber 3 from puncturing the blood vessel wall or diseased tissue. Figure 2 The state shown is as follows: the distal end of the optical fiber 3 extends from the distal end of the catheter 1. In this state, when the laser in the laser therapy device is turned on, the portion of the optical fiber 3 exposed at the distal end of the catheter 1 can achieve ablation of the target tissue within the blood vessel.

[0027] Combining 1 and Figure 3 As shown, when the distal end of the laser treatment balloon catheter encounters a narrowed blood vessel and cannot be further advanced, an expansion medium can be introduced through the inlet 4121 to inflate the balloon 2. The inflated balloon 2 then dilates the blood vessel at a specific point. Once the blood vessel diameter has expanded to an appropriate level, the expansion medium can be discharged in reverse, causing the balloon 2 to return to its contracted state, thereby allowing the laser treatment balloon catheter to be advanced further. Alternatively, according to... Figure 2 As shown, the control component 42 drives the optical fiber 3 to slide within the optical fiber channel 111 to a position where the distal end protrudes, and then performs the ablation operation at that position.

[0028] like Figure 4 As shown, the inflated balloon 2 can also "anchor" the distal end of the laser treatment balloon catheter to a designated location within the blood vessel. In this state, the control component 42 can directly drive the optical fiber 3 to slide within the optical fiber channel 111 until the distal head extends out, allowing the optical fiber 3 to be ablated at a more specific location, thus avoiding direct contact between the optical fiber 3 and the inner wall of the blood vessel.

[0029] It can be seen that balloon 2 can not only dilate blood vessels when necessary, just like the balloon in a conventional balloon catheter, but also, when inflated, balloon 2 can be used to fix the distal end of catheter 1 in the blood vessel, thereby fixing the position of the optical fiber 3 that extends from the catheter 1, not only along the direction of the blood vessel extension, but also keeping the optical fiber 3 in a position approximately at the center of the blood vessel.

[0030] Combination Figure 1 and Figure 3 As shown, the handle seat 41 includes a seat body 411 and an inlet tube 412 connected to the seat body 411. The aforementioned inlet 4121 for introducing the expansion medium into the inlet chamber 13 and the balloon 2 is formed at the inlet of the inlet tube 412.

[0031] The seat 411 has an internal chamber that extends in the same direction as the conduit 1, and the conduit 1 is slidably connected to this internal chamber. The control assembly 42 includes an optical fiber control element for controlling the sliding of the optical fiber 3, and a conduit control element for controlling the sliding of the conduit 1. In the illustrated embodiment, the optical fiber control element is configured as a roller-shaped optical fiber guide wheel 421, and the conduit control element is configured as a roller-shaped conduit guide wheel 422.

[0032] During normal pushing operations, the operator pushes the entire laser treatment balloon catheter forward using the control handle 4, allowing the distal end of the fiber optic cable 3 to quickly and efficiently approach the ablation site. However, in areas close to the ablation site, pushing the entire catheter using the control handle 4 may result in excessive pushing distance, potentially touching or even puncturing a blood vessel. In such cases, slightly moving the catheter element 1 forward along the original pushing direction using the catheter guide wheel 422 allows for more precise control of the speed and position of the distal end of the catheter element 1, avoiding excessive displacement in a single push that could damage the blood vessel.

[0033] The proximal end of the optical fiber 3 protrudes from the fiber optic channel 111 into the internal cavity of the seat 411, allowing the fiber guide wheel 421 to engage with the exposed portion of the optical fiber 3. The fiber guide wheel can roll relative to the handle seat 41, with a portion of its wheel extending through the seat 411 into the internal cavity, thus making positive pressure contact with the exposed portion of the fiber optic channel 1. Driving the exposed portion of the fiber guide wheel 421 from the outside of the seat 411 causes it to rotate. Because the portion of the fiber guide wheel 421 extending into the seat 411 is in positive pressure contact with the optical fiber 3, the rotation of the fiber guide wheel 421 drives the optical fiber 3 to move through friction. This movement drive method is not only convenient to operate, but also, compared to a translational sliding drive method, the rotation of the fiber guide wheel 421 driving the movement of the optical fiber 3 results in higher displacement accuracy and smoother movement of the optical fiber 3.

[0034] The structure of the guide wheel 422 and the principle by which it drives the catheter component 1 to move relative to the seat 411 are similar to those of the fiber optic guide wheel 421. The fiber optic cable 3 is typically a solid structure, and the positive pressure from the fiber optic guide wheel 421 will not cause the fiber optic cable 3 to collapse. In contrast, the catheter component 1 has an annular inlet cavity 13 formed between the inner and outer tube sections to allow the balloon 2 to inflate. If the guide wheel 422 directly applies positive pressure to the outer tube section 12, it may require a certain degree of rigidity in the outer tube section 12, which in turn affects the flexibility of the catheter component 1.

[0035] To resolve this contradiction, in some embodiments, the catheter fitting 1 further includes a control rod portion 14, which is a solid rod body, coaxially connected to the proximal ends of the inner tube portion 11 and the outer tube portion 12. The control rod portion 14, located proximal to the inner and outer tube portions, extends into the inner cavity of the seat body 411 and engages with the catheter guide wheel 422. Thus, due to the solid structure of the control rod portion 14, the positive pressure of the catheter guide wheel 422 will not cause its wall to collapse. Therefore, the catheter guide wheel 422 can more reliably and accurately drive the catheter fitting 1 to slide relative to the handle seat 41.

[0036] In some embodiments, the catheter 1 is configured as a single integrally formed component, with the inner tube 11, outer tube 12, and control rod 14 all integrally formed. Further, the catheter 1 and balloon 2 can also be integrally formed. That is, the distal ends of the outer tube 12 and the inner tube 11 are closedly connected, and the distal end of the outer tube 12 directly forms the balloon 2.

[0037] Of course, the above-mentioned parts can also be set up separately as needed and connected into one piece by laser welding, bonding or other methods. Compared with the separate setting and connection method, the balloon 2 and the catheter 1 are integrally formed, which can save many processes such as welding the proximal and distal ends of the balloon 2 to the catheter 1, greatly simplifying the manufacturing process.

[0038] In some embodiments, the inner diameter of the distal segment of the inner tube 11 is adapted to the diameter of the optical fiber 3, so that the optical fiber 3 can be centrally positioned within the catheter 1. Combined with the positioning effect of the inflated balloon 2, this better ensures that the optical fiber 3 is stably and centrally positioned within the blood vessel.

[0039] In addition, a very fine thermocouple can be installed on the distal inner side of balloon 2. The very fine thermocouple operates based on the Seebeck effect: two metal conductors of different materials are tightly welded at one end to form a measuring end (hot end), and the other end is a reference end (cold end). When there is a temperature difference between the measuring end and the reference end, a thermoelectric electromotive force is generated at the interface of the two metals, forming a weak voltage signal. The magnitude of this voltage has an approximately monotonic relationship with the temperature difference between the two points. By measuring the voltage through the back-end acquisition circuit and performing cold end compensation and linearization calibration, the real-time temperature of the measuring end can be calculated. During the ablation operation on fiber optic 3, the balloon 2 and the distal end of fiber optic 3 are relatively close. The temperature of balloon 2 can reflect the temperature of the target tissue near fiber optic 3 to a certain extent. By detecting and feeding back this temperature through the very fine thermocouple, the operator can promptly predict the risk of thermal damage. In some embodiments, physiological saline can also be used as an expansion medium and circulated to cool the blood vessel.

[0040] In addition to its temperature-sensing function, the index material of the ultra-fine thermocouple can also be used in conjunction with external ultrasound imaging equipment for positioning. This allows for convenient external positioning of the balloon 2 via the ultra-fine thermocouple, thus easily determining the distal position of the current laser treatment balloon catheter externally.

[0041] Another embodiment of this application provides a laser therapy device, which includes a laser and the laser therapy balloon catheter of any of the above embodiments.

[0042] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Although this application has disclosed preferred embodiments as above, it is not intended to limit this application. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the technical solution of this application. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of this application without departing from the content of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A laser therapy balloon catheter, characterized in that, The laser therapy balloon catheter includes a catheter component (1), a balloon (2), an optical fiber (3), and a control handle (4), wherein: The conduit (1) includes an inner tube (11) and an outer tube (12) nested together. The distal end of the inner tube (11) extends beyond the distal end of the outer tube (12). A liquid inlet chamber (13) is formed between the inner tube (11) and the outer tube (12). An optical fiber channel (111) is provided in the inner tube (11) to allow the optical fiber (3) to pass through. The balloon (2) is disposed at the distal end of the catheter (1) and sleeved on the outside of the section of the inner tube (11) that extends out of the outer tube (12). The two ends of the balloon (2) are sealed and connected to the distal ends of the inner tube (11) and the outer tube (12). The control handle (4) includes a handle base (41) and a control component (42). The handle base (41) is provided with an inlet (4121) that communicates with the inlet chamber (13) to introduce an expansion medium into the balloon (2). The proximal end of the optical fiber (3) is slidably connected to the handle base (41) and can be controlled by the control component (42) to slide within the optical fiber channel (111).

2. The laser therapy balloon catheter according to claim 1, characterized in that, The catheter (1) is slidably connected to the handle seat (41). The control component (42) includes an optical fiber control element for controlling the sliding of the optical fiber (3) and a conduit control element for controlling the sliding of the conduit (1).

3. The laser therapy balloon catheter according to claim 2, characterized in that, The proximal end of the optical fiber (3) protrudes from the optical fiber channel (111) within the handle seat (41) of the guide tube (1). The optical fiber control component is configured as an optical fiber guide wheel (421) that can roll relative to the handle seat (41). Part of the wheel of the optical fiber guide wheel (421) extends through the seat body (411) of the handle seat (41) to a position inside the handle seat (41) that can make positive pressure contact with the optical fiber (3).

4. The laser therapy balloon catheter according to claim 2 or 3, characterized in that, The catheter component (1) further includes a control rod portion (14) configured as a solid rod body. The control rod portion (14) is coaxially connected to the proximal end of the inner tube portion (11) and the outer tube portion (12). The catheter component (1) slides relative to the handle seat (41) through the cooperation of the control rod portion (14) and the catheter control component.

5. The laser therapy balloon catheter according to claim 4, characterized in that, The catheter control component is configured as a catheter guide wheel (422) that can roll relative to the handle seat (41), and part of the guide wheel (422) extends through the seat of the handle seat (41) to a position inside the handle seat (41) that can make positive pressure contact with the control lever (14).

6. The laser therapy balloon catheter according to claim 4, characterized in that, The inner tube (11), the outer tube (12), and the control rod (14) are integrally formed.

7. The laser therapy balloon catheter according to claim 6, characterized in that, The catheter (1) is integrally formed with the balloon (2).

8. The laser therapy balloon catheter according to claim 7, characterized in that, The inner diameter of the distal section of the inner tube (11) is adapted to the diameter of the optical fiber (3) so that the optical fiber (3) can be centrally positioned inside the conduit (1).

9. The laser therapy balloon catheter according to claim 1, characterized in that, A very fine thermocouple is provided on the inner side of the distal end of the balloon (2).

10. A laser therapy device, characterized in that, The laser therapy device includes a laser and a laser therapy balloon catheter as described in any one of claims 1-9.

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