Ultrasonic catheter

Abstract

The application provides an ultrasonic catheter, which comprises an outer sheath, an inner core assembly with a transducer and an operating assembly; the outer sheath is detachably coaxially connected with the operating assembly; the proximal end of the inner core assembly is arranged in the operating assembly; the distal end of the inner core assembly is movably arranged in the outer sheath and is used for withdrawing the outer sheath after the operating assembly is separated from the outer sheath; the outer sheath is also used for allowing a stuck wire to pass through after the outer sheath is separated from the operating assembly. In use, the outer sheath is coaxially assembled and connected with the operating assembly, the distal end of the inner core assembly is arranged in the outer sheath, and the ultrasonic probe can be realized after the outer sheath is inserted into the human body. When the outer sheath is removed and stuck, the outer sheath can be separated from the operating assembly, the distal end of the inner core assembly is withdrawn from the outer sheath, the stuck wire is arranged in the outer sheath, and the outer sheath can be driven to be separated from the stuck position through the stuck wire, so that the problem that the outer sheath is difficult to be separated from the stuck position when the outer sheath is withdrawn is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical devices, in particular to an ultrasonic catheter. BACKGROUND

[0002] In recent years, the incidence of coronary heart disease is increasing year by year, which is one of the main causes of cardiovascular and cerebrovascular diseases, so early detection and early diagnosis are particularly important. At present, coronary angiography is a commonly used and effective method for diagnosing coronary heart disease. It is a relatively safe and reliable invasive diagnostic technique and has been widely used in clinical practice and is considered as the "gold standard" for diagnosing coronary heart disease. However, coronary angiography has great limitations in evaluating the characteristics of the tube wall and plaque: first, angiography can only reflect the profile of the vessel lumen filled with contrast agent, and when the degree of coronary artery stenosis is below 40%, angiography cannot detect coronary artery abnormalities; second, due to the fact that the intracoronary lesion is often biased towards one side of the lumen or irregular in shape, the limitations of the angiography projection will also affect the assessment of the degree of vascular stenosis.

[0003] In recent years, new technology intravascular ultrasound (IVUS) imaging has been widely used in interventional cardiology as a new diagnostic tool for evaluating diseased blood vessels (such as arteries) in the human body to determine the need for treatment, guide intervention and / or evaluate its effectiveness. Intravascular ultrasound is a scanning of the blood vessel by a (high frequency) ultrasound emitted from the front end of the IVUS catheter, and the reflected ultrasound signals with blood vessel wall information are used to reconstruct the blood vessel wall structure; the frequency band of intravascular ultrasound is mainly concentrated in 20MHz-80MHz, the higher the frequency, the better the resolution, but the greater the attenuation, and the imaging depth and image contrast will be affected; different blood vessel tissue components have different effects on the signal intensity and frequency (phase) of ultrasound, such as lipid plaques which have weak reflection of ultrasound signals (very dark on the image), and calcium which has strong reflection of ultrasound.

[0004] However, the existing IVUS catheter sometimes has the problem that the position of the guide wire penetrating the IVUS catheter (the guide wire port) often gets stuck in the protrusions such as the blood vessel stent, and the IVUS catheter pulls the blood vessel stent when it is withdrawn, causing the blood vessel stent to deviate from its position, and the more forceful the withdrawal, the tighter the sticking, which can damage the inner wall of the blood vessel and even endanger the patient's life. SUMMARY

[0005] The purpose of the present application is to provide an ultrasonic catheter to solve the problem that the existing ultrasonic catheter is difficult to disengage after being stuck during withdrawal.

[0006] To solve the above technical problems, the present application provides an ultrasonic catheter, which comprises an outer sheath, an inner core assembly with a transducer, and an operating assembly.

[0007] The outer sheath is detachably connected coaxially with the operating assembly;

[0008] The proximal end of the inner core assembly is arranged in the operation assembly; the distal end of the inner core assembly is movably arranged in the outer sheath, and is used for withdrawing the outer sheath after the operation assembly and the outer sheath are separated;

[0009] The outer sheath is also used for allowing the guide wire to pass in after the outer sheath is separated from the operation assembly.

[0010] Optionally, the outer sheath comprises a first clamping structure, the operation assembly comprises a second clamping structure, and the operation assembly and the outer sheath are coaxially clamped and connected or separated through the first clamping structure and the second clamping structure.

[0011] Optionally, one of the first clamping structure and the second clamping structure has a buckle, and the other has a clamping groove matched with the buckle.

[0012] Optionally, one of the first clamping structure and the second clamping structure has a protruding part, and the other has a recessed part matched with the protruding part; the protruding part is tapered and gradually shrinks towards the installation direction of the clamping structure where the protruding part is located, and the recessed part is flared and gradually expands towards the installation direction of the clamping structure where the recessed part is located.

[0013] Optionally, the inner core assembly comprises a base body and a flexible connecting pipe connected in sequence from the proximal end to the distal end.

[0014] The base body is rotatably arranged in the operation assembly, and the base body is connected with the transducer through the flexible connecting pipe to drive the transducer to rotate.

[0015] Optionally, the flexible connecting pipe comprises a hypotube or an inner-outer double-layer spring pipe.

[0016] Optionally, the winding directions of the inner-outer double-layer spring pipe are opposite; and / or, the winding direction of the outer layer of the spring pipe is opposite to the rotating direction of the inner core assembly.

[0017] Optionally, when not subjected to external force, the adjacent spring turns of the spring pipe abut against each other; and / or, when not subjected to external force, the inner-outer double-layer spring pipe abut against each other in the radial direction.

[0018] Optionally, the proximal end of the inner core assembly is rotatably arranged in the operation assembly around the axis of the operation assembly; the inner core assembly is used for rotating in the operation assembly and the outer sheath after the operation assembly and the outer sheath are assembled and connected; the proximal end of the inner core assembly is limited in the axial movement by the operation assembly, and the distal end of the inner core assembly is withdrawn from the outer sheath along with the operation assembly after the operation assembly and the outer sheath are separated.

[0019] Optionally, the outer sheath tube has a containing cavity extending along its own axial direction; the outer sheath tube further has a guide wire cavity, the guide wire cavity penetrating through the outer sheath tube for a guide wire to be arranged therein; the guide wire cavity is arranged at an angle with the containing cavity; the distal end of the containing cavity is closed; and the distal end of the containing cavity is adjacent to the guide wire cavity.

[0020] In summary, the ultrasonic catheter provided by the application comprises an outer sheath tube, an inner core assembly with a transducer, and an operating assembly; the outer sheath tube is coaxially connected with the operating assembly in a detachable manner; the proximal end of the inner core assembly is arranged in the operating assembly; the distal end of the inner core assembly is movably arranged in the outer sheath tube and is used for being withdrawn from the outer sheath tube after the operating assembly is separated from the outer sheath tube; and the outer sheath tube is used for arranging a guide wire to be arranged therein after the outer sheath tube is separated from the operating assembly.

[0021] In this way, during use, the outer sheath tube is coaxially assembled and connected with the operating assembly, the distal end of the inner core assembly is arranged in the outer sheath tube, and ultrasonic exploration can be realized after the outer sheath tube is inserted into the human body. During withdrawal, once the outer sheath tube is stuck, the outer sheath tube can be separated from the operating assembly, the distal end of the inner core assembly is withdrawn from the outer sheath tube, and then the guide wire is arranged in the outer sheath tube, and the outer sheath tube can be driven to be unstuck through the guide wire, thereby solving the problem that the ultrasonic catheter is difficult to be withdrawn after being stuck. BRIEF DESCRIPTION OF DRAWINGS

[0022] Those skilled in the art will understand that the provided drawings are used to better understand the application and do not constitute any limitation on the scope of the application. Among them:

[0023] Figure 1 is a schematic diagram of the ultrasonic catheter of the embodiment of the application;

[0024] Figure 2 is a schematic diagram of the distal end of the outer sheath tube of the embodiment of the application;

[0025] Figure 3 is a schematic diagram of the distal end of the outer sheath tube of the embodiment of the application after the guide wire is arranged therein;

[0026] Figure 4a is a schematic diagram of the inner core assembly of the embodiment of the application;

[0027] Figure 4b is a schematic diagram of the inner core assembly of the embodiment of the application; Figure 4a

[0028] Figures 5a to 5d is a schematic diagram of the double-layer wound spring tube of the embodiment of the application;

[0029] Figure 6 is a schematic diagram of the operating assembly of the embodiment of the application; ​

[0030] Figure 7a is a schematic view of the first clamping structure and the second clamping structure of the embodiment of the present application being connected in clamping;

[0031] Figure 7b is a schematic view of the first clamping structure and the second clamping structure of the embodiment of the present application being separated;

[0032] In the drawings:

[0033] 10-outer sheath tube; 11-receiving cavity; 12-guide wire cavity; 13-liquid outlet; 14-development ring; 15-depth marker ring;

[0034] 20-inner core assembly; 20a-proximal end; 20b-distal end; 21-base; 211-limiting surface; 22-flexible connecting tube; 23-transducer; 24-PCB board; 25-metal sleeve; 26-additional sleeve; 27-protection sleeve;

[0035] 30-operation assembly; 31-liquid inlet; 311-one-way valve; 32-cavity; 33-seal;

[0036] 42-guide wire; 51-first clamping structure; 511-buckle; 512-protruding part; 52-second clamping structure; 521-clamping slot; 522-recessed part. DETAILED DESCRIPTION

[0037] In order to make the purpose, advantages and features of the present application clearer, the present application is further described in detail below in combination with the drawings and specific embodiments. It should be noted that the drawings are all very simplified and not drawn in proportion, and are only used to facilitate and clearly assist the purpose of describing the embodiments of the present application. In addition, the structures shown in the drawings are often part of the actual structures. In particular, the emphasis shown in each drawing is different, and sometimes different proportions are used.

[0038] As used in the present disclosure, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. The term "or" is generally employed in its sense including "and / or" unless the context clearly dictates otherwise. The term "plurality" is generally employed in its sense including "at least one" unless the context clearly dictates otherwise. The term "at least two" is generally employed in its sense including "two or more" unless the context clearly dictates otherwise. In addition, the terms "first," "second," "third," etc. are used only to describe a particular one of a number of similar features and do not imply or suggest a relative importance of the features or imply a number of the features indicated. Thus, features qualified by "first," "second," "third," etc. can expressly or implicitly include one or at least two of the features. The terms "proximal" and "distal" generally refer to two portions that correspond to each other, and do not include only the end points. The terms "proximal" and "distal" are defined herein with respect to an ultrasound catheter having one end for intervention into a human body and a handle end extending out of the body. The term "proximal" refers to a position of an element closer to the handle end of the ultrasound catheter, and the term "distal" refers to a position of an element closer to the one end of the ultrasound catheter for intervention into the human body and thus further away from the handle end of the ultrasound catheter. Alternatively, in a manual or hand-operated application, the terms "proximal" and "distal" are defined herein with respect to an operator such as a surgeon or clinician. The term "proximal" refers to a position of an element closer to the operator, and the term "distal" refers to a position of an element closer to the ultrasound catheter and thus further away from the operator. In addition, as used in the present disclosure, "mounted," "connected," "linked," an element "disposed" on another element should be construed broadly, and generally only indicates that there is a connection, coupling, cooperation or transmission relationship between the two elements, and the connection, coupling, cooperation or transmission between the two elements can be direct or indirect through an intermediate element, and cannot be construed as indicating or implying a spatial positional relationship between the two elements, i.e. an element can be in any position such as inside, outside, above, below or one side of another element, unless the context clearly indicates otherwise. For those skilled in the art, the specific meanings of the above terms in the present disclosure can be understood according to the specific circumstances. In addition, directional terms such as above, below, up, down, upward, downward, left, right, etc. are used with respect to the exemplary embodiments as they are shown in the drawings, with the upward or upward direction being toward the top of the corresponding drawing, and the downward or downward direction being toward the bottom of the corresponding drawing.

[0039] The purpose of the present disclosure is to provide an ultrasound catheter to solve the problem that the existing ultrasound catheter is difficult to disengage after being stuck during withdrawal.

[0040] The following is described with reference to the accompanying drawings.

[0041] Reference is made to Figures 1 to 4bThe embodiment of the present application provides an ultrasonic catheter, which comprises an outer sheath 10, a transducer-equipped inner core assembly 20 and an operating assembly 30; the outer sheath 10 is detachably coaxially connected with the operating assembly 30; a proximal end part 20a of the inner core assembly 20 is arranged in the operating assembly 30; a distal end part 20b of the inner core assembly 20 is movably inserted into the outer sheath 10 and is used to withdraw the outer sheath 10 after the operating assembly 30 is separated from the outer sheath 10; and the outer sheath 10 is also used to insert a guide wire for unclogging after the outer sheath 10 is separated from the operating assembly 30. Figure 4a The division of the proximal end part 20a and the distal end part 20b of the inner core assembly 20 is only exemplarily shown, and the division of the proximal end part 20a and the distal end part 20b can be adjusted according to actual conditions, and the present application is not limited in this aspect.

[0042] In this way, the outer sheath 10 is coaxially assembled and connected with the operating assembly 30 in use, the distal end part 20b of the inner core assembly 20 is inserted into the outer sheath 10, and ultrasonic exploration can be realized after the outer sheath 10 is inserted into the human body; and when the outer sheath 10 is removed, the outer sheath 10 can be separated from the operating assembly 30 once the outer sheath 10 is stuck, the distal end part 20b of the inner core assembly 20 is withdrawn from the outer sheath 10, and then the guide wire for unclogging is inserted into the outer sheath 10, so that the outer sheath 10 can be driven to be unclogged at the stuck position through the guide wire for unclogging, thereby solving the problem that it is difficult to separate the ultrasonic catheter after the ultrasonic catheter is stuck during withdrawal.

[0043] Optionally, the outer sheath 10 has a containing cavity 11 extending along the axis of the outer sheath 10, the containing cavity 11 is open towards the proximal end and is used to insert the inner core assembly 20 or the guide wire for unclogging. In an exemplary embodiment, the inner core assembly 20 comprises a base 21, a flexible connecting pipe 22 and a transducer 23 which are sequentially connected from the proximal end to the distal end, and the transducer 23 is used to convert electric power into mechanical power (i.e. ultrasonic wave) and emit the mechanical power. In the assembling process, the transducer 23 and a part of the flexible connecting pipe 22 are inserted from the proximal end of the containing cavity 11 until the transducer 23 reaches a predetermined position. In this way, the containing cavity 11 is filled with the transducer 23 and the flexible connecting pipe 22, and the guide wire 42 cannot be arranged in the containing cavity 11. However, the outer sheath 10 needs to be guided by the guide wire 42 during the insertion process. Therefore, the outer sheath 10 also has a guide wire cavity 12 which penetrates through the outer sheath 10 and is used to arrange the guide wire 42. In this way, the outer sheath 10 can move forward and backward along the guide wire 42 to be inserted into a predetermined position of the human body.

[0044] Preferably, the axis of the guide wire cavity 12 is arranged at an angle with the axis of the containing cavity 11, the distal end of the containing cavity 11 is closed, and the distal end of the containing cavity 11 is adjacent to the guide wire cavity 12. Figure 3As shown, in one example, the axis of the guidewire cavity 12 forms a small angle (e.g., less than 15°) with the axis of the receiving cavity 11 to reduce the bending angle of the guidewire 42, thus reducing resistance when the outer sheath 10 moves along the guidewire 42. The distal end of the receiving cavity 11 is arranged adjacent to the guidewire cavity 12, which reduces the maximum radial dimension at the point where the outer sheath 10 and the guidewire 42 are parallel. Figure 3 (Point A in the middle) to improve the passage performance of the ultrasonic catheter. In a preferred example, the distal end of the accommodating cavity 11 gradually tapers into a cone shape, and the side of its cone-shaped sidewall adjacent to the guidewire cavity 12 is parallel to the axis of the guidewire cavity 12. This configuration helps to reduce the thickness of the adjacent portion of the accommodating cavity 11 and the guidewire cavity 12, thereby further reducing the maximum radial dimension at the point where the outer sheath 10 and the guidewire 42 are parallel.

[0045] However, no matter how much the maximum radial dimension at the point where the outer sheath 10 and the guidewire 42 are parallel is reduced, it is still the maximum dimension during the entire ultrasound catheter intervention and withdrawal process. In particular, there is a gap between the portion of the guidewire 42 extending proximally from the guidewire lumen 12 and the outer sheath 10, which makes it easy for protrusions (such as vascular stents) in the blood vessel to get stuck during withdrawal. The more force is applied during withdrawal, the tighter the sticking becomes, making it impossible to withdraw the ultrasound catheter smoothly during the procedure. Therefore, in the ultrasound catheter provided in this embodiment, after separating the outer sheath 10 from the operating component 30 and withdrawing the distal end 20b of the core component 20 from the outer sheath 10, the release guidewire is inserted from the proximal end of the receiving cavity 11 until it abuts against the distal end of the outer sheath 10. By pushing the release guidewire further distally, the outer sheath 10 can continue to advance, thereby releasing the stuck protrusion. By appropriately rotating the outer sheath 10 to avoid the protrusion, it can be withdrawn smoothly.

[0046] Optionally, the proximal end 20a of the core component 20 is rotatably disposed within the operating component 30 about the axis of the operating component 30; the core component 20 is used to rotate within the operating component 30 and the outer sheath 10 after the operating component 30 and the outer sheath 10 are assembled and connected. Generally, the distal end 20b of the core component 20 (mainly the transducer 23) needs to move relative to the scanned area to form an image. In this embodiment, the core component 20 is configured to be rotatably disposed within the operating component 30 and the outer sheath 10, and the substrate 21 is rotatably disposed within the operating component 30. The substrate 21 is connected to the transducer 23 through the flexible connecting tube 22 to drive the transducer 23 to rotate. During operation, the transducer 23 rotates at high speed within the outer sheath 10 to acquire the scanning signal of the blood vessel wall.

[0047] Optionally, the proximal end 20a of the inner core assembly 20 is limited in axial movement by the operation assembly 30, and after the operation assembly 30 is separated from the outer sheath 10, the distal end 20b of the inner core assembly 20 is withdrawn from the outer sheath 10 along with the operation assembly 30. Figure 4a In the shown example, the base 21 is limited in axial movement but not in circumferential rotation after being arranged in the operation assembly 30. Optionally, the base 21 has a limiting surface 211 arranged towards the distal end, which is limited by a corresponding part of the operation assembly 30 after being assembled into the operation assembly 30, so that the base 21 cannot move towards the distal end. In this way, the operation assembly 30 can be withdrawn from the outer sheath 10 along with the inner core assembly 20 after being separated from the outer sheath 10.

[0048] Since in use the outer sheath 10 is inserted into the human body and can bend along with the blood vessel, whether the power torque at the proximal base 21 can be effectively (e.g. 1:1) transmitted to the position of the transducer 23 at the distal end is related to whether the ultrasound catheter can be clearly imaged. Both bending and effective torque transmission put high requirements on the specific structure of the flexible connecting tube 22. Please refer to Figures 5a to 5d In one example, the flexible connecting tube 22 comprises a double-layer spring tube. Optionally, the spring tube is tightly wound, i.e. the adjacent spring turns of the spring tube are in close contact with each other when not subjected to external force. Optionally, the double-layer spring tube is in close contact with each other in the radial direction when not subjected to external force. The double-layer spring tube can effectively transmit torque and has good flexibility itself, and can adapt to the curved shape of the blood vessel.

[0049] In some embodiments, the winding directions of the double-layer spring tubes can be the same. For example Figure 5c In the shown example, the winding directions of the double-layer spring tubes are both left-handed (i.e. s direction); Figure 5d In the shown example, the winding directions of the double-layer spring tubes are both right-handed (i.e. z direction). In other embodiments, the winding directions of the double-layer spring tubes are opposite. For example Figure 5a In the shown example, the winding direction of the inner-layer spring tube is right-handed (i.e. z direction), and the winding direction of the outer-layer spring tube is left-handed (i.e. s direction); Figure 5b In the shown example, the winding direction of the inner-layer spring tube is left-handed (i.e. s direction), and the winding direction of the outer-layer spring tube is right-handed (i.e. z direction). When the winding directions of the double-layer spring tubes are opposite, the deformation amounts generated by rotation of the two can be offset, thus achieving good results.

[0050] Preferably, the winding direction of the outer-layer spring tube is opposite to the rotation direction of the inner core assembly 20. For example Figure 5aIn the shown example, the rotation direction of the inner core assembly 20 is rightward, i.e. the inner core assembly 20 rotates clockwise when viewed from the left side to the right side of the outer sheath 10. Figure 5a The outer spring tube will rub against the outer sheath 10, and is configured to rotate in the opposite direction of the inner core assembly 20, which can reduce the deformation of the outer spring tube during transmission. Optionally, the material of the outer spring tube includes stainless steel or nickel-titanium alloy, etc.

[0051] In another example, the flexible connecting tube 22 includes a hypotube. The hypotube is a kind of bendable tube material commonly used in the art, which can bend and have flexibility, and can also transmit torque. Those skilled in the art can select a suitable hypotube as the flexible connecting tube 22 according to the prior art. Optionally, the material of the hypotube includes stainless steel or nickel-titanium alloy, etc.

[0052] Please refer to Figure 6 and refer to Figure 2 Optionally, the operation assembly 30 has a liquid inlet 31, and the outer sheath 10 has a liquid outlet 13. After the operation assembly 30 and the outer sheath 10 are assembled and connected, the liquid inlet 31 communicates with the liquid outlet 13 through the accommodating cavity 11. Because the inner core assembly 20 rotates at high speed in the outer sheath 10 during use, the medium (such as normal saline, etc.) is injected into the liquid inlet 31, and the medium flows out of the liquid outlet 13, which can lubricate the inner core assembly 20. In addition, the medium fills the outer sheath 10, which can also play a coupling role for the transducer 23.

[0053] In an example, the base 21 at the proximal end of the inner core assembly 20 can be connected with a driver (not shown, which can be arranged at the proximal side of the operation assembly 30) through a transmission component (such as a transmission cable, etc.). The driver drives the inner core assembly 20 to rotate through the transmission component. Correspondingly, the operation assembly 30 has a cavity 32 extending through the operation assembly 30 in the axial direction. The cavity 32 can be provided for the transmission component to pass through. Optionally, the liquid inlet 31 is arranged on the cavity 32 at an angle and communicates with the cavity 32, as shown in Figure 6 In the shown example, the liquid inlet 31 is perpendicular to the extension direction of the cavity 32. Of course, in other embodiments, the liquid inlet 31 can intersect with the cavity 32 to form a Y shape, and the present application is not limited thereto. Further, the liquid inlet 31 includes a one-way valve 311 with a standard luer connector, which can prevent the medium from flowing back. Further, the operation assembly 30 includes a sealing member 33 at the proximal end of the cavity 32 (left side in the figure), which is used to seal the transmission component to prevent the medium injected from the liquid inlet 31 from flowing out. Figure 6

[0054] Optionally, please continue to refer to Figure 4a ​In an exemplary embodiment, the inner core assembly 20 further comprises a PCB board 24, a metal sleeve 25, an additional sleeve 26 and a protective sleeve 27. The PCB board 24 is fixedly arranged on the base 21 and has two contacts for electrically connecting with the connecting line (e.g. a coaxial cable) of the transducer 23. The metal sleeve 25 is fixedly arranged on the base 21 and extends from the distal end of the base 21 by a distance, and the flexible connecting tube 22 is arranged in the metal sleeve 25. The metal sleeve 25 can fix and support the proximal end of the flexible connecting tube 22, so as to avoid the stress concentration and the bending and breaking of the proximal end of the flexible connecting tube 22. Optionally, the metal sleeve 25 is made of stainless steel or nickel-titanium alloy. The additional sleeve 26 is arranged outside a part of the flexible connecting tube 22, for example, the additional sleeve 26 can be a heat shrink tube, and the material of the heat shrink tube can be PET, FEP or PTFE. The additional sleeve 26 can isolate the flexible connecting tube 22 from the metal sleeve 25, and further protect the flexible connecting tube 22. The protective sleeve 27 is arranged at the distal end of the flexible connecting tube 22, for example, the protective sleeve 27 is nested in the interior of the flexible connecting tube 22. The interior of the protective sleeve 27 has a cavity, and the transducer 23 is arranged in the cavity. The connecting line of the transducer 23 passes through the interior of the flexible connecting tube 22 and is electrically connected with the contacts of the PCB board 24. In use, the inner core assembly 20 rotates as a whole.

[0055] In an exemplary embodiment, the material of the outer sheath tube 10 is one or a combination of PC, PTFE, PEEK, PEBAX, TUP, PE, tantalum, platinum-iridium alloy, stainless steel, nickel-titanium alloy, gold; the outer sheath tube 10 can be a single-layer tube, or a double-layer or multi-layer tube, and a reinforcing layer can be arranged between the double-layer or multi-layer tubes, the reinforcing layer including but not limited to a braided layer or a spring layer, and the like, and those skilled in the art can reasonably configure the outer sheath tube 10 according to the prior art, and the present application is not limited in this regard.

[0056] Preferably, the hardness of the outer sheath tube 10 gradually decreases from the proximal end to the distal end; and the outer diameter of the outer sheath tube 10 gradually decreases from the proximal end to the distal end. It should be noted that the gradual decrease in hardness and the gradual decrease in outer diameter are not limited to linear changes, but can also be non-linear or stepwise changes, and the present embodiment is not limited in this regard. Preferably, the distal end of the outer sheath tube 10 is provided with a developing ring 14, which facilitates the operator to confirm the intervention position of the outer sheath tube 10. Optionally, a plurality of (e.g. two) depth marker rings 15 can be arranged on the proximal end side of the outer sheath tube 10, which are used to indicate the intervention depth of the outer sheath tube 10.

[0057] Optionally, referring to Figure 7a and Figure 7b , the outer sheath tube 10 comprises a first clamping structure 51, the operating assembly 20 comprises a second clamping structure 52, and the operating assembly 20 and the outer sheath tube 10 are coaxially clamped and connected or separated by the first clamping structure 51 and the second clamping structure 52.

[0058] In one example, the first snap structure 51 is located at the proximal end of the outer sheath 10, and has a snap buckle 511. Correspondingly, the second snap structure 52 is located at the distal end of the operating assembly 20, and has a snap groove 521 which is adapted to the snap buckle 511. In use, the snap buckle 511 is inserted into the snap groove 521, and the two are snapped to achieve the assembly connection. When disassembling, the snap buckle 511 is pressed to separate the snap buckle 511 from the snap groove 521, and then the first snap structure 51 and the second snap structure 52 are moved in the opposite direction, so that the outer sheath 10 is separated from the operating assembly 20. Of course, in other embodiments, the first snap structure 51 can have the snap groove 521, and the second snap structure 52 can have the snap buckle 511, which is not limited by the present application.

[0059] Further, one of the first snap structure 51 and the second snap structure 52 has a protrusion 512, and the other has a recess 522 which is adapted to the protrusion 512; the protrusion 512 is tapered and gradually shrinks towards the installation direction of the snap structure where the protrusion 512 is located, and the recess 522 is flared and gradually expands towards the installation direction of the snap structure where the recess 522 is located. Here, the installation direction of the snap structure is described. If the protrusion 512 is located on the first snap structure 51, for the protrusion 512, the snap structure where the protrusion 512 is located is the first snap structure 51, and the installation direction of the first snap structure 51 is towards the proximal end, that is, the protrusion 512 is tapered and gradually shrinks towards the proximal end. Correspondingly, the recess 522 is located on the second snap structure 52, for the recess 522, the snap structure where the recess 522 is located is the second snap structure 52, and the installation direction of the second snap structure 52 is towards the distal end, that is, the recess 522 is flared and gradually expands towards the distal end. It can be understood that in other embodiments, the protrusion 512 is located on the second snap structure 52, and is tapered and gradually shrinks towards the distal end, and the recess 522 is located on the first snap structure 51, and is flared and gradually expands towards the proximal end. The arrangement of the protrusion 512 and the recess 522 can play a guiding role when the first snap structure 51 and the second snap structure 52 are connected. Specifically, when the first snap structure 51 and the second snap structure 52 are connected, if they are not coaxial, the protrusion 512 will contact the side wall of the recess 522 and be limited by the side wall of the recess 522, so that the protrusion 512 can be guided to the position coaxial with the recess 522.

[0060] It should be noted that, Figure 7a and Figure 7bThe first and second snap structures 51 and 52 shown are only exemplary and not limited to the first and second snap structures 51 and 52, and those skilled in the art can make reasonable improvements to the first and second snap structures 51 and 52 according to actual conditions, and the present embodiment is not limited in this regard.

[0061] In summary, the ultrasonic catheter comprises an outer sheath, an inner core assembly with a transducer, and an operating assembly. The outer sheath is coaxially connected with the operating assembly. The proximal end of the inner core assembly is arranged in the operating assembly. The distal end of the inner core assembly is movably arranged in the outer sheath and is used to withdraw the outer sheath after the operating assembly is separated from the outer sheath. The outer sheath is also used to pass a release guide wire after the outer sheath is separated from the operating assembly. In this way, the outer sheath and the operating assembly are coaxially assembled and connected during use. The distal end of the inner core assembly is arranged in the outer sheath. After the outer sheath is inserted into the human body, ultrasonic exploration can be realized. When the outer sheath is removed, if it is stuck, the outer sheath and the operating assembly can be separated. The distal end of the inner core assembly is withdrawn from the outer sheath. Then the release guide wire is passed into the outer sheath. The outer sheath can be driven to release the stuck position through the release guide wire, thereby solving the problem that the ultrasonic catheter is difficult to disengage after being stuck during withdrawal.

[0062] It should be noted that the above several embodiments can be combined with each other. The above description is only a description of the preferred embodiments of the present application, and does not limit the scope of the present application. Any modification or change made by those skilled in the art according to the above disclosure is within the scope of protection of the claims.

Claims

1. An ultrasonic catheter, characterized by, The utility model relates to a medical device, and particularly relates to a detachable sheath for a guide wire. The detachable sheath comprises: an outer sheath, an inner core assembly with a transducer, and an operating assembly; the outer sheath is detachably coaxially connected with the operating assembly; a proximal end of the inner core assembly is arranged in the operating assembly; a distal end of the inner core assembly is movably arranged in the outer sheath and used for withdrawing the outer sheath after the operating assembly is separated from the outer sheath; the outer sheath is further used for allowing a stuck guide wire to pass through after the outer sheath is separated from the operating assembly; 2. The ultrasonic catheter of claim 1, wherein, the outer sheath has a containing cavity extending along an axis of the outer sheath; the outer sheath further has a guide wire cavity penetrating through the outer sheath and used for allowing a guide wire to pass through; an axis of the guide wire cavity is arranged at an angle with respect to an axis of the containing cavity; a distal end of the containing cavity is closed; the distal end of the containing cavity is adjacent to the guide wire cavity; the distal end of the containing cavity is gradually tapered; a side wall of the tapered distal end of the containing cavity is parallel to the axis of the guide wire cavity.

3. The ultrasonic catheter of claim 2, wherein, the outer sheath comprises a first clamping structure; the operating assembly comprises a second clamping structure; the operating assembly is coaxially clamped and connected with the outer sheath through the first clamping structure and the second clamping structure or is separated from the outer sheath.

4. The ultrasonic catheter of claim 2 or 3, wherein, one of the first clamping structure and the second clamping structure has a clamping buckle; the other has a clamping groove matched with the clamping buckle.

5. The ultrasonic catheter of claim 1, wherein, one of the first clamping structure and the second clamping structure has a protruding portion; the other has a recessed portion matched with the protruding portion; the protruding portion is gradually tapered towards an installation direction of the clamping structure where the protruding portion is located; the recessed portion is gradually flared towards an installation direction of the clamping structure where the recessed portion is located. the inner core assembly comprises, from a proximal end to a distal end, a base body and a flexible connecting tube connected in sequence; 6. The ultrasonic catheter of claim 5, wherein, the base body is rotatably arranged in the operating assembly; the base body is connected with the transducer through the flexible connecting tube to drive the transducer to rotate.

7. The ultrasonic catheter of claim 6, wherein, the flexible connecting tube comprises a hypotube or a spring tube with inner and outer layers.

8. The ultrasonic catheter of claim 6, wherein, the spring tube with inner and outer layers is wound in opposite directions; and / or, the spring tube with outer layer is wound in a direction opposite to a rotating direction of the inner core assembly.

9. The ultrasonic catheter of claim 1, wherein, adjacent spring turns of the spring tube abut each other when no external force is applied; and / or, the spring tube with inner and outer layers abut each other in a radial direction when no external force is applied. the proximal end of the inner core assembly is rotatably arranged in the operating assembly around an axis of the operating assembly; the inner core assembly is used for rotating in the operating assembly and the outer sheath after the operating assembly and the outer sheath are assembled and connected; the proximal end of the inner core assembly is limited to move axially by the operating assembly; the distal end of the inner core assembly is withdrawn from the outer sheath together with the operating assembly after the operating assembly is separated from the outer sheath.

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