Bile duct radio frequency ablation catheter and control methodTechnical Field
The application belongs to the technical field of medical appliances, and particularly relates to a bile duct radio frequency ablation catheter control method.
Background
The existing treatment scheme of the advanced cholangiocarcinoma mainly comprises surgical treatment, radiotherapy and chemotherapy and local treatment, and literature research shows that the radio frequency ablation combined bracket treatment prolongs the survival time of partial patients; is suitable for patients who can not receive operation treatment and radiotherapy and chemotherapy.
The BOSTON corporation radiofrequency ablation catheter, which is an 8 French (2.7 mm), 1.8 m long catheter, was designed for use with a 0.035 inch (0.9 mm) guidewire on PTC or ERCP. If used percutaneously, an introducer of 10 French (3.3 mm) aperture is required. At the tip of the catheter there are two stainless steel ring electrodes spaced 8 mm apart, the distal electrode being 5 mm from the device tip. The resulting heating zone length was 25 mm +/-3 mm. The catheter is used with a radio frequency generator to ablate biliary lesions.
However, the following problems exist with such a radiofrequency ablation catheter for treating bile duct cancer:
1. bile duct stenosis is a peripheral non-uniform stenosis, and the RFA catheter cannot ensure sufficient contact with the tumor surface in a stenotic lesion area;
2. the RFA catheter does not measure the local temperature in real time, the ablation process cannot be performed under direct vision, and the accuracy and safety of ablation are poor. (clinical feedback, inability to operate under direct endoscopic view, inability to be effectively identified whether carbonization or ablation is in place;)
3. The ablation length is fixed, and for long narrow sections, multiple segmented ablations and segmented ablations are needed, so that the positioning requirement is high, the risks that excessive thermal damage to the bile duct wall is easily caused by cross ablation and perforation of the bile duct wall are avoided, and the risks that part of the area is not ablated are avoided.
Disclosure of Invention
The application aims to provide a bile duct radio frequency ablation catheter control method for solving the technical problems.
In order to solve the technical problems, the specific technical scheme of the bile duct radio frequency ablation catheter control method is as follows:
the utility model provides a bile duct radio frequency ablation catheter, includes long handle and outer sheath pipe, long handle and outer sheath pipe one end fixed connection, outer sheath pipe endotheca is equipped with double electrode assembly, double electrode assembly includes front end electrode and rear end electrode, front end electrode and rear end electrode cup joint each other and mutually stretch out and draw back, long handle overcoat is equipped with the electrode handle, the electrode handle includes front end electrode handle and rear end electrode handle, front end electrode handle and front end electrode fixed connection, rear end electrode handle and rear end electrode fixed connection, electrode handle is used for promoting front end electrode and rear end electrode and stretches out and draws back and adjust the interval between front end electrode and the rear end electrode in outer sheath pipe.
Further, the rear end electrode is sleeved on the inner wall of the outer sheath tube, the front end electrode is sleeved on the inner wall of the rear end electrode, the long handle is provided with a first hollow chute penetrating through the long handle body, and the first hollow chute is communicated with the inner wall of the outer sheath tube; the front electrode handle is sleeved outside the long handle, and is provided with a hollow sliding groove II penetrating through the front electrode handle body, and the opening direction of the hollow sliding groove II is overlapped with that of the hollow sliding groove I; the rear electrode handle is sleeved outside the front electrode handle, and the front electrode handle and the rear electrode handle freely slide along the hollow chute of the long handle.
Further, the front electrode handle is provided with a first connector, the rear electrode handle is provided with a second connector, the tail end of the front electrode is connected with the first connector, the tail end of the rear electrode is connected with the second connector, and the first connector and the second connector are connected with an external wire to electrify the double-electrode assembly.
Further, the locking piece is arranged on the rear electrode handle and used for locking the front electrode handle and the rear electrode handle, and the front electrode and the rear electrode can be controlled to stretch and retract simultaneously through the front electrode handle or the rear electrode handle.
Further, the locking piece comprises a locking ring, a lock catch and a push button, the outer wall of the front end electrode handle is provided with two limiting convex rings, the limiting sleeve of the locking ring is arranged in the two limiting convex rings of the outer wall of the front end electrode handle to limit the axial movement of the locking ring, the side walls of the front end electrode handle and the rear end electrode handle are provided with locking holes, when the front end electrode handle and the rear end electrode handle are close to the nearest position, the two locking holes are overlapped, the locking ring is an annular body with an opening, the inner side of one end of the opening of the locking ring is provided with the lock catch, the push button is fixed on the outer side of the locking ring, and the push button is pushed to enable the lock catch to fall into the locking hole, so that the front end electrode handle and the rear end electrode handle are fixed.
Further, the front electrode comprises a front electrode head fixing cap, a front cage electrode and a front electrode wire, wherein the front electrode head fixing cap is fixedly connected with the front cage electrode head, a front electrode tail fixing ring is fixedly connected with the front cage electrode tail, the front electrode wire penetrates into the front electrode tail fixing ring to be fixedly connected with the front cage electrode tail, the front electrode wire is fixedly connected with a connector of a front electrode handle, an insulating layer or an insulating film is coated on the surface from the front electrode tail fixing ring to the tail end of the front electrode wire, and an insulating film or an insulating coating is coated on the surface of the front electrode head fixing cap to ensure that the front electrode is insulated from the rear electrode.
Further, the rear electrode comprises an inner sheath tube, a rear electrode head fixing ring, a rear cage electrode and a rear electrode wire, wherein the rear electrode head fixing ring is fixedly connected with the rear cage electrode head, the rear cage electrode tail is fixedly connected with the rear electrode wire, the rear electrode wire is fixedly connected with a connector II of a rear electrode handle, the inner sheath tube is sleeved outside the rear electrode wire, the head end of the inner sheath tube is fixedly connected with the rear cage electrode tail, the tail end of the inner sheath tube is fixedly connected with the rear electrode handle, the rear electrode head fixing ring is provided with a channel for inserting a front electrode wire of a front electrode, the front electrode wire is inserted into the rear electrode head fixing ring, and is fixedly connected with the front electrode handle through the tail end of the inner sheath tube; when the rear end cage electrode stretches out, the rear end cage electrode automatically expands to a cage shape with a fixed diameter; when the front end electrode is retracted, the front end cage electrode can shrink into the channel of the rear end electrode; when the front end cage electrode stretches out, the front end cage electrode automatically expands to a cage shape with a fixed diameter.
Further, the front end cage-shaped electrode and the rear end cage-shaped electrode are formed by nickel-titanium alloy wires in a hot mode, the nickel-titanium alloy wires comprise 6 nickel-titanium wires, the wire diameter of each nickel-titanium wire is 0.3mm, the distance between every two nickel-titanium wires is smaller than 1.4mm, and the maximum outer diameter of the assembled front end cage-shaped electrode and the maximum outer diameter of the assembled rear end cage-shaped electrode are larger than 4mm.
Further, the front end of the hollow chute I of the long handle is provided with a limiting end face, and when the rear electrode handle moves to the top position of the long handle, the bottom of the connector II in the rear electrode handle is abutted against the limiting end face to limit the continuous advancing of the rear electrode handle; the front end outer wall of the long handle is provided with a limiting circular ring, the front end electrode handle moves forwards until the front end of the front end electrode handle is abutted with the limiting circular ring, and the front end electrode handle moves to the limiting position.
The application also discloses a control method of the bile duct radio frequency ablation catheter, which comprises the following steps:
step one: locking the locking piece, wherein the front electrode handle and the rear electrode handle are in an interlocking state, the front electrode handle is pulled back, the rear electrode handle and the front electrode handle synchronously move, the rear electrode connected with the rear electrode handle is pulled back, and the front electrode connected with the front electrode handle is pulled back simultaneously until the front electrode and the rear electrode enter a channel of the sheath tube;
step two: passing the catheter through the jaws of the duodenoscope;
step three: at this time, the front electrode handle is pushed to enable the front electrode and the rear electrode to move forwards until the end face of the outer sheath tube is completely exposed;
step four: at the moment, according to the focus requirement, an ablation range is confirmed, if a long narrow section is required to be ablated, the locking piece can be rotated, so that the front electrode handle and the rear electrode handle are in an interlocking state, at the moment, the front electrode handle is continuously pushed, and the front electrode is continuously advanced until the maximum ablation length is reached;
step five: when the ablation is finished, the front electrode handle is pulled back to enable the front electrode to enter the inner sheath tube of the rear electrode, then the rear electrode handle is pulled back to enable the rear electrode to enter the outer sheath tube or the locking piece is rotated to enable the front electrode and the rear electrode to be interlocked, and then the front electrode and the rear electrode gradually enter the outer sheath tube through pulling the front electrode handle or the rear electrode handle.
The bile duct radio frequency ablation catheter control method has the following advantages:
1. the electrode has the double-electrode assembly, and the length of the electrode ablatable region is adjustable by adjusting and controlling the electrode handle, so that the disposable ablation of focuses with different lengths is realized.
2. The electrode is an expansion electrode, can be self-adaptively attached to the tumor body, and realizes full ablation.
3. On the basis of the existing catheter, a thermocouple is added to realize a temperature monitoring function, ablation is realized by controlling the ablation temperature and time, and ablation carbonization is avoided.
Drawings
FIG. 1 is a schematic diagram of a bile duct radiofrequency ablation catheter of the present application;
FIG. 2 is a schematic view of a locking element according to the present application;
FIG. 3 is a schematic view of the front electrode structure of the present application;
FIG. 4 is a schematic view of the structure of the rear electrode of the present application;
FIG. 5 is a schematic cross-sectional view of the junction of the rear cage electrode and the rear electrode lead of the present application;
FIG. 6 is a schematic diagram of the sleeving structure of the front electrode and the rear electrode of the application;
FIG. 7 is a schematic cross-sectional view of a bile duct radiofrequency ablation catheter of the present application;
FIG. 8 is a schematic view of the dual electrode assembly of the present application in a retracted sheath configuration;
FIG. 9 is a schematic view showing the maximum distance between the front electrode and the rear electrode of the present application;
the figure indicates: 1. a long handle; 11. a hollow chute I; 12. a finger ring; 13. a limiting end face; 14. a limit circular ring; 2. an outer sheath; 3. a dual electrode assembly; 31. a front electrode; 311. a front electrode head fixing cap; 312. a front cage electrode; 313. a front electrode lead; 314. a front electrode tail fixing ring; 32. A rear electrode; 321. an inner sheath; 322. a rear electrode head fixing ring; 323. a rear cage electrode; 324. a rear electrode lead; 325. a first mounting ring; 326. a second mounting ring; 4. an electrode handle; 41. a front electrode handle; 411. a hollow sliding groove II; 412. a first connector; 413. a limit convex ring; 414. a double finger ring; 42. a rear electrode handle; 421. a second connector; 5. a locking member; 51. a locking ring; 52. locking; 53. a push button; 54. a lock hole; 6. a thermocouple; 61. thermocouple wires.
Detailed Description
For a better understanding of the objects, structures and functions of the present application, a bile duct radiofrequency ablation catheter and control method of the present application will be described in further detail with reference to the accompanying drawings.
As shown in fig. 1, the bile duct radiofrequency ablation catheter comprises a long handle 1 and an outer sheath tube 2, wherein the long handle 1 is fixedly connected with one end of the outer sheath tube 2, the maximum diameter of the outer sheath tube 2 is less than or equal to 2.9mm, and the bile duct radiofrequency ablation catheter can pass through a forceps channel of 3.2 of a duodenal mirror. The double-electrode assembly 3 is sleeved in the outer sheath tube 2, the double-electrode assembly 3 comprises a front electrode 31 and a rear electrode 32, the rear electrode 32 is sleeved on the inner wall of the outer sheath tube 2, the front electrode 31 is sleeved on the inner wall of the rear electrode 32, the long handle 1 is provided with a first hollow chute 11 penetrating through the body of the long handle 1, and the first hollow chute 11 is communicated with the inner wall of the outer sheath tube 2. The long handle 1 is sleeved with the electrode handle 4, the electrode handle 4 comprises a front electrode handle 41 and a rear electrode handle 42, the front electrode handle 41 is sleeved outside the long handle 1, the front electrode handle 41 is provided with a hollow sliding groove II 411 penetrating through the body of the front electrode handle 41, and the hollow sliding groove II 411 is overlapped with the opening direction of the hollow sliding groove I11. The rear electrode handle 42 is sleeved outside the front electrode handle 41, the tail end of the front electrode 31 is fixedly connected with the front electrode handle 41, the tail end of the rear electrode 32 is fixedly connected with the rear electrode handle 42, and the front electrode handle 41 and the rear electrode handle 42 can freely slide along the hollow chute 11 of the long handle 1, so that the front electrode 31 and the rear electrode 32 can be adjusted to stretch and retract inside and outside the outer sheath tube 2, and the distance between the front electrode 31 and the rear electrode 32 can be adjusted.
The front electrode handle 41 is provided with a first connector 412, the rear electrode handle 42 is provided with a second connector 421, the tail end of the front electrode 31 is connected with the first connector 412, the tail end of the rear electrode 32 is connected with the second connector 421, and the first connector 412 and the second connector 421 are connected with an external wire to electrify the double electrode assembly 3.
The rear electrode handle 42 is provided with a locking element 5, and the locking element 5 is used for locking the front electrode handle 41 and the rear electrode handle 42, and the front electrode 31 and the rear electrode 32 can be controlled to stretch and retract simultaneously through the front electrode handle 41 or the rear electrode handle 42.
As shown in fig. 2, the locking element 5 includes a locking ring 51, a locking buckle 52 and a push button 53, the outer wall of the front electrode handle 41 has two limiting convex rings 413, the limiting sleeve of the locking ring 51 is arranged in the two limiting convex rings 413 of the outer wall of the front electrode handle 41, the axial movement of the locking ring 51 is limited, and the limiting convex rings 413 can also be limiting grooves. The side walls of the front end electrode handle 41 and the rear end electrode handle 42 are respectively provided with a lock hole 54, when the front end electrode handle 41 and the rear end electrode handle 42 are close to the nearest positions, the two lock holes 54 are overlapped, the lock ring 51 is an annular body with an opening, so that the lock ring 51 has elasticity in the radial direction, a lock catch 52 is arranged at the inner side of one end of the opening of the lock ring 51, a push button 53 is fixed at the outer side of the lock ring 51, and the push button 53 is pushed to enable the lock catch 52 to fall into the lock hole 54, so that the front end electrode handle 41 and the rear end electrode handle 42 are fixed.
The end of the long handle 1 is provided with a finger ring 12, the end of the front electrode handle 41 is provided with a double finger ring 414, the thumb is sleeved on the finger ring 12 of the long handle 1, the index finger and the middle finger are sleeved on the double finger ring 414 of the front electrode handle 41, and the electrode handle 4 can be operated in a telescopic way by one hand.
As shown in fig. 3, the front electrode 31 includes a front electrode head fixing cap 311, a front cage electrode 312, a front electrode lead 313 and a front electrode tail fixing ring 314, the front electrode head fixing cap 311 is fixedly connected with the front cage electrode 312 head, the front electrode tail fixing ring 314 is fixedly connected with the front cage electrode 312 tail, the front electrode lead 313 penetrates into the front electrode tail fixing ring 314 to be fixedly connected with the front cage electrode 312 tail, and the front electrode lead 313 is fixedly connected with a connector 412 of the front electrode handle 41. The front electrode lead 313 is a wire or rope, typically nickel titanium or stainless steel 304, and an insulating layer or an insulating film is coated from the front electrode tail fixing ring 314 to the end surface of the front electrode lead 313, and an insulating film or an insulating coating is coated on the surface of the front electrode head fixing cap 311 to ensure that the front electrode 31 is insulated from the rear electrode 32. The front cage electrode 312 is formed by nickel titanium alloy wires, and comprises at least 4 nickel titanium wires, preferably 6-8 nickel titanium wires, so that the distance between the nickel titanium wires is less than 1.4mm, and the ablation uniformity is better. The maximum outer diameter of the assembled cage electrode 312 is more than 4mm, the wire diameter of the preferable nickel titanium wire is 0.3mm, and the alloy wire can have adaptive rigidity and toughness through parameter allocation of heat treatment molding.
As shown in fig. 4, the rear electrode 32 includes an inner sheath 321, a rear electrode head fixing ring 322, a rear cage electrode 323 and a rear electrode wire 324, the rear electrode head fixing ring 322 is fixedly connected with the rear cage electrode 323, the rear cage electrode 323 is fixedly connected with the rear electrode wire 324 at the tail, and the rear electrode wire 324 is fixedly connected with the second connector 421 of the rear electrode handle 42. The shape and material of the rear cage electrode 323 are the same as those of the front cage electrode 312. The inner sheath 321 is sleeved outside the rear electrode wire 324, the head end is fixedly connected with the tail of the rear cage electrode 323, and the tail end is fixedly connected with the rear electrode handle 42. As shown in fig. 5, the connection part between the tail part of the rear end cage electrode 323 and the inner sheath 321 is provided with a first mounting ring 325 and a second mounting ring 326, the rear end cage electrode 323 and the second mounting ring 326 are fixedly connected, preferably welded, the first mounting ring 325 is mounted on the surface of the inner sheath 321, the first mounting ring 325 is annularly contracted by high-speed rotary swaging, and the inner sheath 321 is shaped and deformed, so that the first mounting ring 325, the inner sheath 321 and the second mounting ring 326 are integrated. As shown in fig. 6, the rear electrode head fixing ring 322 has a passage into which the front electrode lead 313 of the front electrode 31 is inserted, and the front electrode lead 313 inserted into the rear electrode head fixing ring 322 is fixedly connected to the front electrode handle 41 through the tip of the inner sheath 321. When the rear electrode 32 is retracted, the rear cage electrode 323 can be retracted into the outer sheath 2; when the rear end cage electrode 323 is extended, it can be automatically expanded to a cage shape with a fixed diameter. When the front electrode 31 is retracted, the front cage electrode 312 can retract into the passageway of the rear electrode 32; the tip cage electrode 312 can be automatically expanded to a cage shape of a fixed diameter when extended.
The inner sheath 321 is preferably a multi-cavity sheath, a thermocouple 6 is installed in one cavity of the multi-cavity sheath, and the head of the thermocouple 6 is fixedly connected with one of the nickel titanium wires. The end of the thermocouple 6 is fixedly connected with the second connector 421 of the rear electrode handle 42 through a thermocouple wire 61. The thermocouple 11 can monitor the temperature of the tissue in contact with the electrode in real time.
As shown in fig. 1 and 7, the front end of the hollow chute one 11 of the long handle 1 is provided with a limiting end surface 13, and when the rear electrode handle 42 moves to the top position of the long handle 1, the bottom of the connector two 421 in the rear electrode handle 42 abuts against the limiting end surface 13 to limit the continuous progress of the rear electrode handle 42.
The front end outer wall of the long handle 1 is provided with a limiting circular ring 14, the front end electrode handle 41 moves forwards until the front end of the front end electrode handle 41 is abutted with the limiting circular ring 14, and the front end electrode handle 41 moves to the limiting position.
The bile duct radio frequency ablation catheter control method comprises the following steps:
step one: the locking member 5 is locked, the front electrode handle 41 and the rear electrode handle 42 are in an interlocked state, the front electrode handle 41 is pulled back, the rear electrode handle 42 moves synchronously with the front electrode handle 41, the rear electrode 32 connected with the rear electrode handle 42, and the front electrode 31 connected with the front electrode handle 41 is simultaneously retracted as shown in fig. 8 until both the front electrode 31 and the rear electrode 32 enter the passage of the outer sheath 2.
Step two: the catheter is passed through the jaws of the duodenoscope.
Step three: at this time, the front electrode handle 41 is pushed to move the front electrode 31 and the rear electrode 32 forward until the end face of the outer sheath 2 is completely exposed.
Step four: at this time, according to the lesion requirement, the ablation range is confirmed, if the overlong narrow section needs to be ablated, the locking piece 5 can be rotated, so that the front electrode handle 41 and the rear electrode handle 42 are in an interlocking state, at this time, the front electrode handle 41 is continuously pushed, and the front electrode 31 is continuously advanced until the maximum ablation length is reached, as shown in fig. 9. (the positional relationship between the stricture and the ablation electrode can be confirmed by cholangiography, and the extension length of the tip electrode 31 can be appropriately adjusted). The distance between the front electrode 31 and the rear electrode 32 is adjustable within a range L of 20-30mm.
Step five: when ablation is completed, the front electrode handle 41 is pulled back to bring the front electrode 31 into the inner sheath 321 of the rear electrode 32, and then the rear electrode handle 42 is pulled back to bring the rear electrode 32 into the outer sheath 2 (or the locking element 5 is rotated to interlock the front electrode 31 and the rear electrode 32, and then the front electrode 31 and the rear electrode 32 are gradually brought into the outer sheath 2 by pulling the front electrode handle 41 or the rear electrode handle 42).
It will be understood that the application has been described in terms of several embodiments, and that various changes and equivalents may be made to these features and embodiments by those skilled in the art without departing from the spirit and scope of the application. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the application without departing from the essential scope thereof. Therefore, it is intended that the application not be limited to the particular embodiment disclosed, but that the application will include all embodiments falling within the scope of the appended claims.