CN213465296U - Spray cryoablation catheter - Google Patents

Abstract

The utility model provides a spray cryoablation catheter, which comprises a spray head structure at the far end, a catheter structure in the middle and a handle structure at the near end; the spray head structure comprises a spray pipe and a plugging balloon structure in the spray pipe; the catheter structure comprises an inflow pipe, a balloon communicating pipe and a return pipe sleeved outside the inflow pipe and the balloon communicating pipe which are arranged in parallel; the far end of the return pipe is hermetically connected with the near end of the spray pipe, and the near end of the return pipe is connected with a return pipe connector through a return pipe adapter in the handle structure; the far end of the balloon communicating pipe is fixedly connected with the plugging balloon structure, and the near end of the balloon communicating pipe is connected with the balloon communicating pipe joint; the far end of the inflow pipe is close to the far end of the return pipe, and the near end of the inflow pipe is connected with the inflow pipe joint; the expansion and contraction of the blocking balloon structure are controlled by introducing gas into the balloon communicating pipe, so that the spraying or backflow state of the refrigerant introduced into the inflow pipe is controlled. The utility model has the advantages of simple structure, easy operation, precise freezing range and precise and controllable freezing time.

Description

Spray cryoablation catheter

Technical Field

The utility model relates to the field of medical equipment, especially, relate to a spray cryoablation catheter.

Background

The freezing technology is used for treating airway diseases for more than 40 years, the traditional freezing method needs to directly contact a freezing probe with lesion tissues or insert the freezing probe into the lesion tissues, and due to the limitation of the surface area of the probe, the freezing probe usually has slow effect and long time consumption and is suitable for lesions with smaller range. In 2005, Johnston first proposed the concept of spray freezing, which was successfully used in Barratt esophageal patients. The novel freezing probe is fully distributed with the radial spraying small holes, greatly improves the freezing efficiency, and is more suitable for wide range and irregular lesions on the surface. Spray freezing has accumulated a lot of experience in the field of gastroesophageal barrat and esophageal cancer.

Spraying and freezing can be used for treating pathological changes with rich blood supply and high water content. The spraying freezing therapy of malignant tumor has unique advantages, the malignant tumor generally has rich blood supply, the direct biopsy forceps for removing the tumor often causes obvious bleeding, the freezing and thawing speed of the traditional contact method is low, the freezing and thawing often causes large bleeding amount in the operation, bleeding points are difficult to locate, rapid hemostasis cannot be realized, and the operation is difficult. The spraying and freezing can rapidly and repeatedly freeze-thaw the tumor, so that the blood supply of the tumor body is reduced, and the bleeding amount in the operation can be reduced. Therefore, the operation visual field is clear, and the possible damage of the airway wall caused by blind operation is avoided.

The application of the spray freezing technology in the diseases in the airway cavity is relatively safe and has certain effect, and the spray freezing technology is characterized in that:

(1) the non-contact use is adopted, the injury is uniformly distributed, and meanwhile, the probe adhesion and the tissue tearing caused by contact treatment are avoided;

(2) can rapidly stop bleeding in a large area and reduce the operation time;

(3) limited lesion depth, about 2mm, is not prone to airway perforation;

(4) as with contact freezing, there is no risk of airway fire;

(5) no high-frequency electric effect, thus being applicable to patients with pacemakers;

(6) the method has no damage to metal or silicone scaffold, and can be used for treating benign and malignant tissue hyperplasia in scaffold with minimal effect of stimulating granulation tissue hyperplasia.

The spray freezing technology is non-contact, and a large area can be rapidly frozen through liquid nitrogen spraying (-196 ℃), the depth is larger, the cell damage is more complete, and the treatment effect is more consistent. The results suggest that spray freezing technology can be safely used for airway treatment, and the spray freezing technology has little damage to interstitial tissues while killing target tissue cells. Gas generated by spraying and freezing needs to be discharged from an air passage, so that the air passage pressure is increased to generate cardiovascular system complications, pneumothorax and mediastinum emphysema, the freezing spray pipe and the working hole passage of the bronchoscope can be frozen and the like due to long-time operation, and the method is very important for controlling the freezing and spraying time.

Therefore, it is an urgent technical problem to provide a method for accurately controlling the spraying and freezing time and ensuring the safety during the operation process.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that spray the not accurate defect inadequately of freezing time control among the prior art, provide one kind can the accurate control cryogenic fluid spray scope and freezing time spray the freezing pipe.

The utility model discloses a solve above-mentioned technical problem and adopt following technical scheme:

a spray cryoablation catheter includes a distal tip structure, a central catheter structure, and a proximal handle structure; the spray head structure comprises a spray pipe and a plugging balloon structure in the spray pipe; the catheter structure comprises an inflow tube, a balloon communicating tube and a return tube, wherein the inflow tube and the balloon communicating tube are arranged in parallel, and the return tube is sleeved outside the inflow tube and the balloon communicating tube; the far end of the return pipe is hermetically connected with the near end of the spray pipe, and the near end of the return pipe is connected with a return pipe connector through a return pipe adapter in the handle structure; the far end of the balloon communicating pipe is fixedly connected with the plugging balloon structure, and the near end of the balloon communicating pipe is connected with the balloon communicating pipe joint; the far end of the inflow pipe is close to the far end of the return pipe, and the near end of the inflow pipe is connected with an inflow pipe joint; and gas is introduced into the balloon communicating pipe to control the expansion and contraction of the blocking balloon structure, so that the spraying or backflow state of the refrigerant introduced into the inflow pipe is controlled.

Preferably, the blocking balloon structure is one of a single balloon structure, a double-balloon sleeving structure and a double-balloon series structure.

Preferably, the occlusion balloon structure is a single balloon structure, and the occlusion balloon structure comprises an occlusion balloon; the plugging saccule is connected with the far end of the saccule communicating pipe in a sealing way.

Preferably, the distal end face of the nozzle is provided with an axial nozzle hole.

Preferably, the blocking balloon structure is a double-balloon sleeving structure, and comprises an inner blocking balloon and an outer blocking balloon which are sequentially sleeved from inside to outside; the near end of the inner plugging balloon is hermetically connected with the outer surface of the inner balloon communicating pipe; the outer plugging saccule is hermetically connected with the far end of an outer saccule communicating pipe sleeved outside the inner saccule communicating pipe; and an opening is arranged on the inner sacculus communicating pipe positioned in the inner plugging sacculus.

Preferably, radial spray holes are formed in the two sides, corresponding to the tube wall of the outer plugging balloon portion, of the spray tube.

Preferably, the occlusion balloon structure is a double-balloon series structure, and the occlusion balloon structure comprises an axial occlusion balloon and a radial occlusion balloon which are sequentially arranged from a far end to a near end; the near end of the radial plugging saccule is hermetically connected with the far end of the radial saccule communicating pipe, and the inner wall of the far end of the radial plugging saccule is hermetically connected with the outer wall of the axial saccule communicating pipe sleeved in the radial saccule communicating pipe; the far end of the axial balloon communicating pipe extends out of the radial plugging balloon, the far end of the axial balloon communicating pipe is connected with the far end of the axial plugging balloon in a sealing mode, and an opening is formed in the part, located in the axial plugging balloon, of the axial balloon communicating pipe.

Preferably, the far end face of the spray pipe is provided with an axial spray hole; and radial spray holes are formed in the two sides of the pipe wall of the spray pipe, which correspond to the radial plugging sacculus part.

Preferably, the conduit structure further comprises a vacuum tube sleeved outside the return pipe.

Preferably, the far-end inner wall of the vacuum tube is hermetically connected with the far-end outer wall of the return tube, and the near end of the vacuum tube is connected with the vacuum tube joint through a vacuum tube adapter.

The utility model adopts the above technical scheme, compare with prior art, have following technological effect:

the utility model provides a spray cryoablation catheter, adopt the technical method who sets up the shutoff sacculus, through the spraying volume of the accurate control refrigerant of the air volume of control in the shutoff sacculus, spray time and spray the scope, both avoided freezing time overlength to hurt normal tissue, avoided freezing time not enough can't completely eliminate pathological change tissue again, reduced the trouble of secondary operation, alleviateed patient's pain; the invention also has the advantages of simple structure and simple and convenient operation.

Drawings

Fig. 1 is a schematic structural view of a spray cryoablation catheter of the present invention;

fig. 2 is a schematic structural view of an embodiment 1 of a spray cryoablation catheter according to the present invention;

fig. 3 is a schematic cross-sectional view of embodiment 1 of a spray cryoablation catheter of the present invention;

fig. 4 is a schematic structural view of embodiment 2 of a spray cryoablation catheter of the present invention;

fig. 5 is a schematic cross-sectional view of embodiment 2 of a spray cryoablation catheter of the present invention;

fig. 6 is a schematic structural view of embodiment 3 of a spray cryoablation catheter of the present invention;

the reference numerals denote the description:

1-nozzle structure, 11-plugging saccule, 111-external plugging saccule, 112-internal plugging saccule, 113-radial plugging saccule, 114-axial plugging saccule, 12-jet pipe, 121-radial jet hole, 122-axial jet hole,

2-catheter structure, 21-inflow tube, 22-reflux tube, 23-vacuum tube, 24-balloon communicating tube, 241-outer balloon communicating tube, 242-inner balloon communicating tube, 243-radial balloon communicating tube, 244-axial balloon communicating tube,

3-handle structure, 31-inflow pipe joint, 32-backflow pipe joint, 33-vacuum pipe joint, 34-balloon communicating pipe joint, 35-backflow pipe adapter and 36-vacuum pipe adapter.

Detailed Description

The technical solution of the present invention will be further described in detail with reference to the accompanying drawings. In the following embodiments, proximal refers to the end near the operator and distal refers to the end near the patient.

Example 1

Referring to fig. 1-3, the present embodiment provides a spray cryoablation catheter including a distal nozzle structure 1, a middle catheter structure 2, and a proximal handle structure 3; the spray head structure 1 comprises a spray pipe 12 and a plugging balloon structure in the spray pipe 12; the catheter structure 2 comprises an inflow pipe 21 and a balloon communicating pipe 24 which are arranged in parallel and a return pipe 22 sleeved outside the inflow pipe and the balloon communicating pipe; the far end of the return pipe 22 is hermetically connected with the near end of the spray pipe 12, and the near end is connected with the return pipe connector 32 through a return pipe adapter 35 in the handle structure 3; the far end of the balloon communicating pipe 24 is fixedly connected with the plugging balloon structure, and the near end is connected with the balloon communicating pipe joint 34; the far end of the inflow pipe (21) is close to the far end of the return pipe (22), and the near end is connected with an inflow pipe joint (31); the expansion and contraction of the blocking balloon structure are controlled by introducing gas into the balloon communicating tube 24, so that the spraying or backflow state of the refrigerant introduced into the inflow tube 21 is controlled.

In this embodiment, as shown in fig. 2, the occlusion balloon structure is a single balloon structure, and the occlusion balloon structure includes an occlusion balloon 11; the plugging saccule 11 is connected with the far end of the saccule communicating tube 24 in a sealing way.

In this embodiment, as shown in fig. 2, the nozzle structure 1 includes a nozzle 12, and the distal end surface of the nozzle 12 is provided with axial nozzle holes 122.

In this embodiment, as in FIG. 2, the occlusion balloon 11 may be located within the return tube 22.

In this embodiment, as shown in fig. 2, the catheter structure 2 further includes a vacuum tube 23 sleeved outside the return tube 22.

In this embodiment, as shown in FIG. 2, the inner wall of the vacuum tube 23 at the distal end is hermetically connected to the outer wall of the return tube 22 at the distal end, and the proximal end is connected to the vacuum tube connector 33 through a vacuum tube adapter 36.

The spray cryoablation catheter working principle provided in this implementation:

in the precooling stage, the balloon communicating pipe joint 34 is connected with external inflating equipment to inflate the plugging balloon 11 through the balloon communicating pipe 24, and the plugging balloon 11 expands, so that the passage of the inflow pipe 21 and the jet pipe 12 is plugged; then, the inlet pipe joint 31 is connected with external equipment to be introduced, and the refrigerant flows into the inlet pipe 21 and flows out from the return pipe 22 and the return pipe joint 32;

in the ablation stage, the plugging balloon 11 is evacuated, the plugging of the nozzle 12 is cancelled, and the refrigerant is sprayed out through the axial nozzle hole 122 to perform cryoablation on the target tissue.

Example 2

Referring to fig. 4-5, the present embodiment provides a spray cryoablation catheter, which includes a distal nozzle structure 1, a middle catheter structure 2, and a proximal handle structure 3; the spray head structure 1 comprises a spray pipe 12 and a plugging balloon structure in the spray pipe 12; the catheter structure 2 comprises an inflow pipe 21 and a balloon communicating pipe 24 which are arranged in parallel and a return pipe 22 sleeved outside the inflow pipe and the balloon communicating pipe; the far end of the return pipe 22 is hermetically connected with the near end of the spray pipe 12, and the near end is connected with the return pipe connector 32 through a return pipe adapter 35 in the handle structure 3; the distal end of the inflow pipe 21 is connected to the inflow pipe joint 31 near the distal end of the return pipe 22.

In this embodiment, as shown in fig. 4, the blocking balloon structure is a double-balloon sleeving structure, and includes an inner blocking balloon 112 and an outer blocking balloon 111 sleeved in sequence from inside to outside; the balloon communication tube 24 includes an inner balloon communication tube 242 and an outer balloon communication tube 241 sleeved outside the inner balloon communication tube 242; the far end of the inner plugging balloon 112 is hermetically connected with the far end of the inner balloon communicating pipe 242, and the near end of the inner plugging balloon 112 is fixed on the outer surface of the inner balloon communicating pipe 242; the far end of the outer plugging balloon 111 is hermetically connected with the far end of the inner balloon communicating tube 242, and the near end of the outer plugging balloon 111 is hermetically connected with the far end of the outer balloon communicating tube 241; an opening is provided on the inner balloon communicating tube 242 positioned in the inner occlusion balloon 112.

The expansion and contraction of the outer occlusion balloon 111 are controlled by introducing gas into the outer balloon communication tube 241, thereby controlling the state of the refrigerant introduced into the inflow tube 21 being discharged or returned. The expansion and contraction of the inner occlusion balloon 112 are controlled by introducing gas into the inner balloon communication tube 242, and the amount of the refrigerant liquid sprayed from the radial nozzle holes 121 is controlled. When the inner plugging balloon 112 is expanded and the outer plugging balloon 111 is expanded, the refrigerant flows back from the return pipe 22; when the inner blocking spherical bag 112 contracts, the outer blocking spherical bag 111 contracts, the refrigerant liquid is sprayed out from the radial spray holes 121, and the spraying amount is large; when the inner plugging ball bag 112 expands, the outer plugging ball bag 111 contracts, and the refrigerant fluid is sprayed out from the radial spray holes 121, so that the spraying amount is small.

In this embodiment, as shown in fig. 4, radial injection holes 121 are formed on two sides of the tube wall of the portion of the injection tube 12 corresponding to the outer occlusion balloon 111. The radial injection holes 121 are radially arranged on two sides of the tube wall of the injection tube 12, and the positions of the radial injection holes 121 correspond to the positions of the blocking balloon structures, so that the radial injection holes 121 can be blocked after the balloon structures are expanded.

In this embodiment, as shown in fig. 4, the catheter structure 2 further includes a vacuum tube 23 sleeved outside the return tube 22.

In this embodiment, as shown in FIG. 4, the inner wall of the distal end of the vacuum tube 23 is sealingly connected to the outer wall of the distal end of the return tube 22, and the proximal end is connected to the vacuum tube connector 33 via a vacuum tube adapter 36.

The spray cryoablation catheter working principle provided in this implementation:

in the pre-cooling stage, the outer balloon communicating tube 241 is connected to an external inflating device to inflate the outer plugging balloon 111, so that the outer plugging balloon 111 expands to plug the radial nozzle 121, and the refrigerant fluid flows in from the flow tube 21 and flows out from the return tube 22.

In the ablation stage, when the tissue of a patient is large and the amount of refrigerant liquid is needed, the outer plugging saccule 111 is evacuated, and the refrigerant liquid is sprayed out from the radial spray holes 121; when the tissues of a patient are smaller and less refrigerating fluid is needed, the inner blocking balloon 112 is inflated and expanded firstly, then the outer blocking balloon 111 is evacuated, the diameter of the inner blocking balloon 112 is smaller than that of the outer blocking balloon 111, a small amount of refrigerating fluid can flow out from a gap between the inner blocking balloon 112 and the inner wall of the spray pipe 12 and is sprayed to the tissues of the patient, and a large amount of refrigerating fluid can be prevented from damaging normal tissues.

Example 3

Referring to fig. 6, the present embodiment provides a spray cryoablation catheter, which includes a distal nozzle structure 1, a middle catheter structure 2 and a proximal handle structure 3; the spray head structure 1 comprises a spray pipe 12 and a plugging balloon structure in the spray pipe 12; the catheter structure 2 comprises an inflow pipe 21 and a balloon communicating pipe 24 which are arranged in parallel and a return pipe 22 sleeved outside the inflow pipe and the balloon communicating pipe; the far end of the return pipe 22 is hermetically connected with the near end of the spray pipe 12, and the near end is connected with the return pipe connector 32 through a return pipe adapter 35 in the handle structure 3; the distal end of the inflow pipe 21 is close to the distal end of the return pipe 22, and the proximal end is connected to an inflow pipe joint 31.

In this embodiment, as shown in fig. 6, the occlusion balloon structure is a double-balloon series structure, and the occlusion balloon structure includes an axial occlusion balloon 114 and a radial occlusion balloon 113 that are sequentially arranged from a distal end to a proximal end; the balloon communicating tube 24 includes a radial balloon communicating tube 243 and an axial balloon communicating tube 244 sleeved in the radial balloon communicating tube 243; the near end of the radial plugging balloon 113 is hermetically connected with the far end of the radial balloon communicating tube 243, and the inner wall of the far end is hermetically connected with the outer wall of the axial balloon communicating tube 244; the distal end of the axial balloon communicating tube 244 extends out of the radial occlusion balloon 113, the distal end thereof is connected with the distal end of the axial occlusion balloon 114 in a sealing manner, and the part of the axial balloon communicating tube located in the axial occlusion balloon 114 is provided with an opening.

The expansion and contraction of the radial occlusion balloon 113 and the axial occlusion balloon 114 are controlled by introducing gas into the radial balloon communication tube 243 and the axial balloon communication tube 244, respectively. When the axial plugging balloon 114 expands and the radial plugging balloon 113 contracts, the refrigerant is only sprayed out from the radial spray holes 121; when the axial plugging balloon 114 contracts and the radial plugging balloon 113 contracts, the refrigerant is sprayed out from the radial spray hole 121 and the axial spray hole 122; when the axial occlusion balloon 114 is expanded and the radial occlusion balloon 113 is expanded, the refrigerant flows back from the return pipe 22.

In the present embodiment, as shown in fig. 6, the distal end surface of the nozzle 12 is provided with an axial nozzle 122; two sides of the pipe wall of the part of the jet pipe 12 corresponding to the radial plugging saccule 113 are provided with radial jet holes 121.

The opening of the axial spray hole 122 is in the shape of a horn mouth, and the freezing liquid can be sprayed directionally, so that the freezing liquid is sprayed to the front diseased tissue, and the freezing liquid is prevented from being sprayed to the normal tissue on the two sides. The radial nozzle 121 is positioned to cooperate with the radial occlusion balloon 113 so that the radial nozzle 121 can be occluded after the radial occlusion balloon 113 is expanded.

In this embodiment, as shown in fig. 6, the catheter structure 2 further includes a vacuum tube 23 sleeved outside the return tube 22.

In this embodiment, as shown in FIG. 6, the inner wall of the distal end of the vacuum tube 23 is sealingly connected to the outer wall of the distal end of the return tube 22, and the proximal end is connected to the vacuum tube connector 33 via a vacuum tube adapter 36.

The spray cryoablation catheter working principle provided in this implementation:

in the pre-cooling stage, the radial balloon communicating tube 243 is connected to an external inflating device to inflate the radial blocking balloon 113, so that the radial blocking balloon 113 is expanded to block the radial nozzle 121, and meanwhile, the refrigerant liquid is prevented from flowing to the axial nozzle 122, and flows in from the flow tube 21 and flows out from the return tube 22.

In the ablation stage, when patient tissues are arranged on two sides of the wall of the lumen and in front of the wall of the lumen, and the spraying amount of the refrigerant liquid is required to be large, the radial blocking balloon 113 is evacuated, and the refrigerant liquid is sprayed out from the radial spray holes 121 and the axial spray holes 122 simultaneously; when the patient tissues are only positioned at two sides of the nozzle 12 and the front is normal tissues, the axial blocking balloon 114 is inflated and expanded, the axial jet holes 122 are blocked by the axial blocking balloon 114, then the radial blocking balloon 113 is evacuated, and the refrigerant is jetted out from the radial jet holes 121 to the patient tissues at two sides of the lumen, so that the damage to the front normal tissues can be avoided.

The present invention has been described in detail with reference to the specific embodiments, but the present invention is only by way of example and is not limited to the specific embodiments described above. Any equivalent modifications and substitutions to the disclosed embodiments are within the scope of the present invention as those skilled in the art will recognize. Accordingly, variations and modifications in equivalents may be made without departing from the spirit and scope of the invention, which is intended to be covered by the following claims.

Claims (10)

1. A spray cryoablation catheter comprising a distal spray head structure (1), a central catheter structure (2) and a proximal handle structure (3); the spray head structure (1) comprises a spray pipe (12) and a plugging balloon structure in the spray pipe (12); the catheter structure (2) comprises an inflow tube (21), a balloon communicating tube (24) and a return tube (22) sleeved outside the inflow tube and the balloon communicating tube which are arranged in parallel; the far end of the return pipe (22) is hermetically connected with the near end of the spray pipe (12), and the near end of the return pipe is connected with a return pipe connector (32) through a return pipe adapter (35) in the handle structure (3); the far end of the balloon communicating pipe (24) is fixedly connected with the plugging balloon structure, and the near end of the balloon communicating pipe is connected with a balloon communicating pipe joint (34); the far end of the inflow pipe (21) is close to the far end of the return pipe (22), and the near end is connected with an inflow pipe joint (31); the balloon communicating pipe (24) is filled with gas to control the expansion and contraction of the blocking balloon structure, so that the spraying or backflow state of the refrigerant filled in the inflow pipe (21) is controlled.

2. The spray cryoablation catheter of claim 1 wherein the occlusion balloon structure is one of a single balloon structure, a double balloon sleeved structure, and a double balloon in-line structure.

3. The spray cryoablation catheter of claim 2, wherein the occlusion balloon structure is a single balloon structure comprising an occlusion balloon (11); the plugging saccule (11) is connected with the far end of the saccule communicating pipe (24) in a sealing way.

4. The spray cryoablation catheter according to claim 3, wherein the distal end face of the nozzle tube (12) is provided with axial nozzle holes (122).

5. The spray cryoablation catheter of claim 2, wherein the occlusion balloon structure is a double-balloon sheathing structure, and comprises an inner occlusion balloon (112) and an outer occlusion balloon (111) which are sheathed in sequence from inside to outside; the near end of the inner plugging saccule (112) is hermetically connected with the outer surface of the inner saccule communicating tube (242); the outer plugging balloon (111) is hermetically connected with the far end of an outer balloon communicating pipe (241) sleeved outside the inner balloon communicating pipe (242); and an opening is arranged on the inner balloon communicating pipe (242) positioned in the inner plugging balloon (112).

6. The spray cryoablation catheter according to claim 5, wherein the nozzle (12) is provided with radial nozzles (121) on both sides of the wall of the portion of the outer occlusion balloon (111).

7. The spray cryoablation catheter of claim 2, wherein the occlusion balloon structure is a double balloon tandem structure comprising an axial occlusion balloon (114) and a radial occlusion balloon (113) arranged sequentially from a distal end to a proximal end; the near end of the radial plugging balloon (113) is hermetically connected with the far end of the radial balloon communicating pipe (243), and the inner wall of the far end is hermetically connected with the outer wall of the axial balloon communicating pipe (244) sleeved in the radial balloon communicating pipe (243); the far end of the axial balloon communicating pipe (244) extends out of the radial blocking balloon (113), the far end of the axial balloon communicating pipe is connected with the far end of the axial blocking balloon (114) in a sealing mode, and an opening is formed in the part, located in the axial blocking balloon (114), of the axial balloon communicating pipe.

8. The spray cryoablation catheter according to claim 7, wherein the distal end face of the nozzle tube (12) is provided with axial nozzle holes (122); radial jet holes (121) are formed in the two sides of the tube wall of the jet tube (12) corresponding to the radial plugging saccule (113).

9. The spray cryoablation catheter according to claim 1, wherein the catheter structure (2) further comprises a vacuum tube (23) sleeved outside the return tube (22).

10. The spray cryoablation catheter of claim 9, wherein the inner distal wall of the vacuum tube (23) is sealingly connected to the outer distal wall of the return tube (22) and the proximal end is connected to a vacuum tube connector (33) via a vacuum tube adapter (36).

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