CN219271916U - Balloon catheter and ablation system - Google Patents

Abstract

The utility model provides a balloon catheter and an ablation system, wherein the balloon catheter comprises a catheter body, a balloon and an ultrasonic transducer, wherein the balloon and the ultrasonic transducer are arranged at the distal end of the catheter body, the catheter body is provided with a conveying channel which is axially extended along the catheter body, the inner cavity of the balloon is communicated with the conveying channel, and the conveying channel is used for conveying filling media to the balloon so as to expand the balloon; the catheter body comprises an outer tube and an inner tube, the outer tube is sleeved outside the inner tube, the distal end of the outer tube is connected with the proximal end of the balloon, the inner tube penetrates through the balloon, and the distal end of the balloon is connected with the distal end of the inner tube; the ultrasonic transducer is used for monitoring the attaching state of the balloon and the target tissue when the balloon is in an expanded state. The utility model can utilize the sound wave to monitor the bonding state of the saccule and the target tissue, thereby improving the treatment effect.

Description

Balloon catheter and ablation system

Technical Field

The utility model relates to the technical field of medical instruments, in particular to a balloon catheter and an ablation system.

Background

Currently, in the field of interventional medical devices, interventional surgical procedures using a balloon into the tissue of a target area are one common surgical procedure. For example, in the medical treatment field, the catheter is used to transfer cold energy, and then tissue freezing is achieved, so that tissues in a target area are frostbitten and lose physiological functions, and the method is one of more common means, and typical application scenes include tumor freezing treatment, atrial fibrillation freezing treatment and the like. The distal end of the therapeutic catheter is usually provided with a refrigerating device, and after entering the human body and reaching the corresponding therapeutic target position, a refrigerating medium (such as liquid nitrogen, nitrous oxide and the like) is conveyed by the equipment connected with the proximal end of the catheter, and then the refrigerating device at the distal end of the catheter is driven to work, so that tissues are frostbitten, and tissue ablation is performed.

In the interventional operation process, the abutting condition between the balloon and the tissue needs to be monitored in real time, for example, in the refrigeration process, if the abutting condition between the balloon and the tissue is not monitored in real time, the low temperature generated by the refrigeration medium may not completely cover the tissue around the balloon. And the balloon can not uniformly refrigerate the peripheral tissues in the treatment process, and the conditions of insufficient local tissue freezing temperature, poor ablation effect, relapse after treatment and the like can exist.

In the current interventional surgical treatment process, a better scheme for monitoring the abutting state between the balloon and surrounding tissues in real time is lacking.

Disclosure of Invention

The utility model aims to provide a balloon catheter and an ablation system, which utilize sound waves to monitor the bonding state of a balloon and target tissues and improve the treatment effect.

In order to achieve the above object, the present utility model provides a balloon catheter, which includes a catheter body, a balloon provided at a distal end of the catheter body, and an ultrasonic transducer, the catheter body having a delivery channel extending in an axial direction thereof, an inner cavity of the balloon being in communication with the delivery channel, the delivery channel being for delivering an inflation medium to the balloon to expand the balloon; the catheter body comprises an outer tube and an inner tube, the outer tube is sleeved outside the inner tube, the distal end of the outer tube is connected with the proximal end of the balloon, the inner tube penetrates through the balloon, and the distal end of the balloon is connected with the distal end of the inner tube; the ultrasonic transducer is used for monitoring the attaching state of the balloon and the target tissue when the balloon is in an expanded state.

Optionally, the ultrasonic transducer is located in the balloon, and the ultrasonic transducer is sleeved on the inner tube.

Optionally, the ultrasonic transducer is located outside the balloon, and the ultrasonic transducer is located at a junction of a distal end of the balloon and a distal end of the inner tube.

Optionally, the ultrasonic transducer is located outside the balloon, and the ultrasonic transducer is located at a junction of a proximal end of the balloon and a distal end of the outer tube.

Optionally, the ultrasonic transducer is externally coated with a shell with no edges and corners on the outer surface.

Optionally, the acoustic impedance value of the housing is between the acoustic impedance value of the filling medium and the acoustic impedance value of the ultrasonic transducer.

Optionally, the ultrasonic transducer includes a hollow base and a plurality of transducer bodies disposed on the base.

The utility model also provides an ablation system comprising a controller and the balloon catheter according to any one of the above, wherein the controller is in communication connection with the ultrasonic transducer and is configured to control the position of the balloon according to the bonding state of the balloon and target tissue monitored by the ultrasonic transducer.

Optionally, the balloon catheter further comprises a refrigerant tube extending through the delivery channel, the refrigerant tube configured to deliver a refrigerant medium to the balloon.

Optionally, a distal end of the refrigerant tube is provided with a head end which is spirally arranged, and at least one hole is formed in the head end.

Optionally, the ablation system further comprises a temperature sensor in communication with the controller, the temperature sensor being disposed at the distal end of the balloon catheter.

The balloon catheter and the ablation system provided by the utility model have the following beneficial effects:

the balloon catheter provided by the utility model comprises a catheter body, a balloon arranged at the distal end of the catheter body and an ultrasonic transducer, wherein the catheter body is provided with a conveying channel which is axially extended along the catheter body, the inner cavity of the balloon is communicated with the conveying channel, and the conveying channel is used for conveying filling media to the balloon so as to expand the balloon; the catheter body comprises an outer tube and an inner tube, the outer tube is sleeved outside the inner tube, the distal end of the outer tube is connected with the proximal end of the balloon, the inner tube penetrates through the balloon, and the distal end of the balloon is connected with the distal end of the inner tube; the ultrasonic transducer is used for monitoring the attaching state of the balloon and the target tissue when the balloon is in an expanded state. Therefore, after the balloon is filled with filling media, the balloon is inflated, the ultrasonic transducer utilizes the acoustic wave reflection principle and the Doppler effect of fluid, so that the acoustic signals received by the ultrasonic transducer when the balloon fails to be completely attached to the tissues around the balloon are different from the acoustic signals received when the balloon is completely attached to the tissues around the balloon after being inflated, different ultrasonic images can be correspondingly generated, and the attachment condition between the balloon and the tissues is monitored in real time.

Because the ablation system provided by the utility model comprises the balloon catheter provided by the utility model, the ablation system provided by the utility model can realize the effect of monitoring the abutting condition between the balloon and the tissue in real time.

Drawings

FIG. 1 is a cross-sectional view of a balloon catheter provided in a first embodiment of the present utility model;

FIG. 2 is a schematic view of a balloon catheter according to a first embodiment of the present utility model applied to tissue;

FIG. 3 is a cross-sectional view of a balloon catheter provided by a second embodiment of the present utility model;

FIG. 4 is a schematic view of a balloon catheter according to a second embodiment of the present utility model applied to tissue;

FIG. 5 is a cross-sectional view of a balloon catheter provided by a third embodiment of the present utility model;

fig. 6a is a schematic structural diagram of an ultrasonic transducer according to a first embodiment of the present utility model;

fig. 6b is a schematic structural diagram of an ultrasonic transducer according to a second embodiment of the present utility model;

FIG. 7 is a block diagram of an ablation system according to an embodiment of the present utility model;

wherein, the reference numerals are as follows:

1-a catheter body; 11 an outer tube; 12-an inner tube;

2-balloon;

3-an ultrasonic transducer; 31-a housing; 32-an ultrasonic transducer cable; 301-an ultrasonic transducer body; 302-an ultrasonic transducer base;

4-refrigerant tubes; 41-a helical head end;

5-a temperature measurement cable;

100-balloon catheter; 200-a controller; 300-display.

Detailed Description

The utility model will be described in further detail with reference to the drawings and the specific embodiments thereof in order to make the objects, advantages and features of the utility model more apparent. It should be noted that the drawings are in a very simplified form and are not drawn to scale, merely for convenience and clarity in aiding in the description of embodiments of the utility model. Furthermore, the structures shown in the drawings are often part of actual structures. In particular, the drawings are shown with different emphasis instead being placed upon illustrating the various embodiments.

It will be understood that when an element or layer is referred to as being "on" or "connected to" another element or layer, it can be directly on, connected to, or intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on" …, "directly connected to" another element or layer, there are no intervening elements or layers present. Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present utility model. Spatially relative terms, such as "under … …," "below," "lower," "above … …," "upper," and the like, may be used herein for convenience of description to describe one element or feature's relationship to another element or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use and operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements or features described as "under" … … "," below "and" beneath "would then be oriented" on "other elements or features. The device may be otherwise oriented (rotated 90 degrees or other orientations) and the spatially relative descriptors used herein interpreted accordingly. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups. As used herein, the term "and/or" includes any and all combinations of the associated listed items.

The term "distal" as used herein refers to the end of the balloon catheter that is distal to the operator after being delivered into the human body, and the term "proximal" as used herein refers to the end of the balloon catheter that is proximal to the operator after being delivered into the human body.

The utility model aims to provide a balloon catheter and an ablation system, which utilize sound waves to monitor the bonding state of a balloon and target tissues and improve the treatment effect.

In order to achieve the above-mentioned objects, the present utility model provides a balloon catheter, please refer to fig. 1 to 2, fig. 1 is a cross-sectional view of a balloon catheter according to a first embodiment of the present utility model; fig. 2 is a schematic view of a balloon catheter according to a first embodiment of the present utility model applied to tissue. As shown in fig. 1 to 2, the balloon catheter comprises a catheter body 1, a balloon 2 arranged at the distal end of the catheter body 1 and an ultrasonic transducer 3, wherein the catheter body 1 is provided with a conveying channel extending along the axial direction of the catheter body, the inner cavity of the balloon 2 is communicated with the conveying channel, and the conveying channel is used for conveying filling medium to the balloon 2 so as to expand the balloon 2; the catheter body 1 comprises an outer tube 11 and an inner tube 12, the outer tube 11 is sleeved outside the inner tube 12, the distal end of the outer tube 11 is connected with the proximal end of the balloon 2, the inner tube 12 penetrates through the balloon 2, and the distal end of the balloon 2 is connected with the distal end of the inner tube 12; the ultrasonic transducer 3 is used for monitoring the fitting state of the balloon 2 and target tissues when the balloon 2 is in an expanded state. The ultrasonic transducer 3 uses the acoustic wave reflection principle and the doppler effect of the fluid, so that the acoustic signal received by the ultrasonic transducer 3 when the balloon 2 fails to be completely attached to the tissue around the balloon 2 is different from the acoustic signal received when the balloon 2 is completely attached to the tissue around the balloon 2 after being inflated, thereby being capable of correspondingly generating different ultrasonic images, and further realizing the effect of monitoring the attachment condition between the balloon 2 and the tissue in real time according to the ultrasonic images.

The following description of the technical solution of the utility model proceeds with reference to different embodiments.

Referring to fig. 1 and 2, in the first embodiment of the present utility model shown in fig. 1 and 2, the ultrasonic transducer 3 is located in the balloon 2, and the ultrasonic transducer 3 is sleeved on the inner tube 12. Referring to fig. 2, as can be seen from fig. 2, when the lumen of the balloon 2 is filled with filling medium, the balloon 2 is inflated, and when the balloon 2 is not attached to the surrounding tissue, the ultrasonic waves emitted from the ultrasonic transducer 3 are reflected back to the tissue surface through the filling medium, the balloon wall of the balloon 2, and the medium between the balloon 2 and the tissue (such as blood in a blood vessel), and are received again by the ultrasonic transducer 3. When the balloon 2 is abutted against the peripheral tissue, the ultrasonic waves emitted by the ultrasonic transducer 3 are reflected back directly by the tissue surface after passing through the filling medium and the balloon wall of the balloon 2. Specifically, if the balloon 2 is well abutted against the tissue, there is little blood present between the balloon 2 and the tissue, and when the acoustic signal passes through the balloon 2 to reach the tissue, the feedback blood signal is weak, or even cannot be fed back; when the balloon 2 is not well abutted against the tissue, the acoustic signal can feed back a stronger blood signal when passing between the balloon 2 and the tissue. The ultrasonic image of the position of the balloon 2 in the cavity and the condition of the abutting and blocking can be synthesized through ultrasonic signals. Since the acoustic signal received by the ultrasonic transducer 3 when the balloon 2 fails to completely abut against the tissue around the balloon 2 is different from the acoustic signal received when the balloon 2 is completely abutting against the tissue around the balloon 2 after inflation, the corresponding generated ultrasonic image is also different, and thus the purpose of monitoring the abutting condition between the balloon 2 and the tissue in real time can be achieved by the generated ultrasonic image.

With continued reference to fig. 1 and 2, as shown in fig. 1 and 2, the ultrasonic transducer 3 is externally covered with a casing 31 having no corner on the outer surface. The outer surface of the housing 31 is free of corners, which protects the ultrasound transducer 3 and ensures that the balloon 2 is not damaged in case the housing 31 might come into contact with the balloon 2. Although fig. 1 and 2 illustrate the case 31 as an ellipsoidal configuration, it should be understood by those skilled in the art that this is not a limitation of the present utility model, and the case 31 may have other shapes as long as no corner angle is ensured on the outer surface of the case 31.

Further, the acoustic impedance value of the housing 31 is between the acoustic impedance value of the filling medium and the acoustic impedance value of the ultrasonic transducer 3. The acoustic impedance value is determined by the nature of the material itself, and in one exemplary embodiment, the housing 31 may be made of an epoxy material with additives added to the epoxy to adjust the acoustic impedance value of the housing 31. Therefore, by adding the additive, the acoustic impedance value of the housing 31 can be adjusted to be an average value of the acoustic impedance value of the filling medium and the acoustic impedance value of the ultrasonic transducer 3, so that when the ultrasonic transducer 3 is positioned in the balloon 2 and the ultrasonic transducer 3 is sleeved on the inner tube 12, good propagation gradient can be formed when the ultrasonic waves propagate between the ultrasonic transducer 3 and the filling medium, and the monitoring precision of the ultrasonic transducer 3 is improved. In addition, the shell 31 is made of epoxy resin, so that the ultrasonic transducer 3 can be better fixed on the distal end of the catheter body 1 by using the viscosity of the epoxy resin, and the pipe section where the ultrasonic transducer 3 is placed can be polished by sand paper, so that the epoxy resin can obtain better fixing effect.

Preferably, a pull wire (not shown) is provided on the catheter body 1, and the pull wire is used for bending the catheter body 1. By the arrangement, when an operator uses the balloon catheter, the balloon catheter can be adjusted by utilizing the stay wire according to the condition of the internal space of the tissue, so that the balloon catheter is attached to the surface of the tissue as much as possible or smoothly moves in the tissue. It will be appreciated that a plurality of pull wires may be provided to effect bending of the catheter body 1 in different directions.

Preferably, the balloon 2 comprises an inner balloon and an outer balloon, the material of the inner balloon is a compliant material, and the material of the outer balloon is a non-compliant material. The double-layer balloon is more puncture-resistant, and can better prevent the leakage of filling media. And the outer balloon is made of non-compliant materials, so that the balloon 2 can be limited to prevent the balloon 2 from being expanded out of order.

Preferably, the surface of the balloon 2 is provided with folds, so that the balloon 2 forms folding wings which are wrapped on the catheter body in a state of not being filled with the filling medium. The balloon 2 can be provided with folds and shaped by using the memory material when the balloon 2 is processed, so that the balloon 2 can automatically form folding wings coated on the catheter body 1 in a state of not being filled with the filling medium, namely in a state of being empty and flat, and the passing outer diameter of the balloon catheter can be reduced.

Referring to fig. 3 and 4, fig. 3 is a cross-sectional view of a balloon catheter according to a second embodiment of the present utility model;

fig. 4 is a schematic view of a balloon catheter according to a second embodiment of the present utility model applied to tissue. As shown in fig. 3 and 4, the balloon catheter according to the second embodiment of the present utility model is different from the balloon catheter according to the first embodiment of the present utility model in that, in the second embodiment, the ultrasonic transducer 3 is located outside the balloon 2, and the ultrasonic transducer 3 is located at a distal end side of the balloon, preferably, the ultrasonic transducer 3 is located at a junction of a distal end of the balloon and a distal end of the inner tube. As shown in fig. 4, preferably, the ultrasonic ring device 3 may be placed at a predetermined angle relative to the axial direction of the catheter body 1, so as to optimize the directionality of the ultrasonic signal and obtain a clearer echo detection result.

Referring to fig. 4, it can be seen from fig. 4 that when the lumen of the balloon 2 is filled with filling medium, the balloon 2 is inflated, when the balloon 2 is not abutted against the peripheral tissue, the medium (such as blood in a blood vessel) between the balloon 2 and the tissue flows, and when the balloon 2 is abutted against the peripheral tissue, the medium (such as blood in a blood vessel) between the balloon 2 and the tissue cannot flow because of being blocked by the balloon 2. According to the doppler effect, the wavelength of the wave is varied by the relative movement of the source and the observer, in this case the medium between the balloon 2 and the tissue (e.g. blood in a blood vessel), the wave being the ultrasound reflected by the source and the observer being the ultrasound transducer 3. Specifically, since ultrasonic waves have a doppler effect on a moving substance, when the balloon 2 is not sealed well, blood flow around the balloon 2 is disturbed when blood flows in the gap between the balloon 2 and the tissue. The close-fitting blocking effect of the balloon 2 can be indirectly judged by monitoring the disturbance condition of blood flow through ultrasonic waves. Meanwhile, the intensity of blood flow disturbance in the region reflects the position where the balloon 2 cannot be abutted against the blocking position. Accordingly, the acoustic signal received by the ultrasonic transducer 3 when the balloon 2 fails to completely abut on the tissue around the balloon 2 is different from the acoustic signal received when the balloon 2 is completely abutting on the tissue around the balloon 2 after inflation, and thus the corresponding generated ultrasonic image is also different, so that the purpose of monitoring the abutting condition between the balloon 2 and the tissue in real time can be achieved by the generated ultrasonic image. When the balloon catheter is applied to cryoablation, the abutted balloon 2 transfers cold to the tissue where the balloon 2 is abutted in the freezing stage, so that the tissue is frozen and crystallized. Because the sound velocity of the solid and the sound velocity of the liquid are obviously different, frozen and crystallized tissues and unfrozen and crystallized tissues are obviously different in ultrasonic detection, the frozen depth of the tissues can be judged, so that the monitoring of the frozen state in the treatment process is optimized, the freezing treatment effect of the balloon catheter is better evaluated, and incomplete freezing or incomplete freezing is avoided.

With continued reference to fig. 5, as shown in fig. 5, the balloon catheter according to the third embodiment of the present utility model is different from the balloon catheter according to the first embodiment of the present utility model in that, in the third embodiment, the ultrasonic transducer 3 is located outside the balloon 2, and the ultrasonic transducer 3 is located at a proximal end side of the balloon 2, preferably, the ultrasonic transducer 3 is located at a junction between a proximal end of the balloon 2 and a distal end of the outer tube. It should be noted that, as those skilled in the art can understand, the principle of the third embodiment is the same as that of the second embodiment, and will not be described herein.

Fig. 6a and fig. 6b are schematic structural diagrams of an ultrasonic transducer according to a first embodiment of the present utility model; fig. 6b is a schematic structural diagram of an ultrasonic transducer according to a second embodiment of the present utility model. As shown in fig. 6a and 6b, the ultrasonic transducer 3 includes a hollow ultrasonic transducer base 30 and a plurality of transducer bodies 301 disposed on the ultrasonic transducer base 30. In order for the ultrasonic transducer 3 to uniformly release and receive ultrasonic waves for better imaging effect, the ultrasonic transducer body 301 should be uniformly disposed in the ultrasonic transducer base 302 of the ultrasonic transducer 3 to form an array of the ultrasonic transducer bodies 301, and the ultrasonic transducer bodies 301 may form an interleaved array in the ultrasonic transducer base 302 (see fig. 6 a) or may form a side-by-side array (see fig. 6 b). When the ultrasonic transducer 3 is placed in the balloon 2, the ultrasonic transducer 3 is of an annular hollow structure, is sleeved on the inner tube 12, and can be arranged at a position on the inner tube 12 corresponding to the maximum diameter of the balloon 2. It should be appreciated that the distal end of the balloon catheter may also include a visualization ring that may be visualized under X-rays to locate the position of the distal end of the balloon catheter.

The present utility model further provides an ablation system, please refer to fig. 7, fig. 7 is a block diagram of an ablation system according to an embodiment of the present utility model. As shown in fig. 7, the ablation system includes a controller 200 and the balloon catheter 100 as described above, the controller 200 being communicatively connected to the ultrasound transducer 3 using an ultrasound transducer cable 32. Because the ablation system comprises the balloon catheter, the ablation system can monitor the abutting condition between the balloon and the tissue in real time.

Further, the ablation system further comprises a display 300 communicatively connected to the controller, wherein the display 300 is configured to display the fit state of the balloon 2 with the target tissue, which is monitored by the ultrasonic transducer 3.

Referring to fig. 1 to 4, the balloon catheter is applied to the ablation system for cryoablation, and when a refrigerant medium enters the balloon 2 through the refrigerant tube 4, the balloon 2 is contacted with tissue of a treatment area to cryoablate the tissue of the treatment area. The ablation system further comprises a temperature sensor in communication connection with the controller, wherein the temperature sensor is arranged at the far end of the balloon catheter, the temperature sensor can be a temperature measuring cable 5, and the temperature sensor of the temperature measuring cable 5 can be arranged at an output port position close to the refrigerant tube 4 so as to be used for detecting refrigeration temperature and preventing supercooling. Furthermore, a vent pipe penetrating through the conveying channel can be arranged between the double-layer sacculus to pump air between the double-layer sacculus, so that cold energy can be better transmitted from the sacculus. Preferably, the distal end of the refrigerant tube 4 is provided with a spiral head 41, and at least one hole is formed in the spiral head 41. During refrigeration, the refrigeration medium is sprayed out through the holes and then evaporated for refrigeration. It should be appreciated that the balloon catheter is not limited to cryoablation applications.

It should be noted that, in the present description, each embodiment is described in a progressive manner, and each embodiment is mainly described in a different manner from other embodiments, and identical and similar parts between the embodiments are all enough to refer to each other. For the system disclosed in the embodiment, the description is relatively simple because of corresponding to the method disclosed in the embodiment, and the relevant points refer to the description of the method section.

It should be further noted that although the present utility model has been disclosed in the preferred embodiments, the above embodiments are not intended to limit the present utility model. Many possible variations and modifications of the disclosed technology can be made by anyone skilled in the art without departing from the scope of the technology, or the technology can be modified to be equivalent. Therefore, any simple modification, equivalent variation and modification of the above embodiments according to the technical substance of the present utility model still fall within the scope of the technical solution of the present utility model.

It should be further understood that the terms "first," "second," "third," and the like in this specification are used merely for distinguishing between various components, elements, steps, etc. in the specification and not for indicating a logical or sequential relationship between the various components, elements, steps, etc., unless otherwise indicated.

It should also be understood that the terminology described herein is for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present utility model. It must be noted that, as used herein and in the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. For example, reference to "a step" or "an apparatus" means a reference to one or more steps or apparatuses, and may include sub-steps as well as sub-apparatuses. All conjunctions used should be understood in the broadest sense. And, the word "or" should be understood as having the definition of a logical "or" rather than a logical "exclusive or" unless the context clearly indicates the contrary. Further, implementation of embodiments of the present utility model may include performing selected tasks manually, automatically, or in combination.

Claims (10)

1. The balloon catheter is characterized by comprising a catheter body, a balloon arranged at the distal end of the catheter body and an ultrasonic transducer, wherein the catheter body is provided with a conveying channel which is axially extended along the catheter body, the inner cavity of the balloon is communicated with the conveying channel, and the conveying channel is used for conveying filling media to the balloon so as to expand the balloon;

the catheter body comprises an outer tube and an inner tube, the outer tube is sleeved outside the inner tube, the distal end of the outer tube is connected with the proximal end of the balloon, the inner tube penetrates through the balloon, and the distal end of the balloon is connected with the distal end of the inner tube;

the ultrasonic transducer is used for monitoring the attaching state of the balloon and the target tissue when the balloon is in an expanded state.

2. The balloon catheter of claim 1, wherein the ultrasound transducer is located within the balloon and the ultrasound transducer is sleeved on the inner tube.

3. The balloon catheter of claim 1, wherein the ultrasound transducer is located outside the balloon, the ultrasound transducer being located at a junction of a distal end of the balloon and a distal end of the inner tube; or,

the ultrasonic transducer is positioned outside the balloon, and the ultrasonic transducer is positioned at the joint of the proximal end of the balloon and the distal end of the outer tube.

4. The balloon catheter of claim 1, wherein the ultrasound transducer is externally covered with a housing having no corners on an outer surface.

5. The balloon catheter of claim 4, wherein an acoustic impedance value of the housing is between an acoustic impedance value of the filling medium and an acoustic impedance value of the ultrasound transducer.

6. The balloon catheter of claim 1, wherein the ultrasound transducer comprises a hollow base and a plurality of transducer bodies disposed on the base.

7. An ablation system comprising a controller in communication with the ultrasound transducer and the balloon catheter of any of claims 1-6, the controller configured to control the position of the balloon based on the condition of the balloon against the target tissue as monitored by the ultrasound transducer.

8. The ablation system of claim 7, wherein the balloon catheter further comprises a refrigerant tube extending through the delivery channel, the refrigerant tube configured to deliver a refrigerant medium to the balloon.

9. The ablation system of claim 8, wherein the distal end of the refrigerant tube is provided with a helically disposed head end having at least one hole formed therein.

10. The ablation system of claim 7, further comprising a temperature sensor in communication with the controller, the temperature sensor being disposed at a distal end of the balloon catheter.

Images