Freezing probes and related methods

Abstract

A freezing probe comprising (a) a handle, (b) a shaft located distal to the handle and having a generally rigid proximal portion and a generally flexible distal portion, and (c) an active tip located distal to the shaft, wherein the shaft includes a supply conduit configured to supply freezing fluid to the active tip, a discharge conduit configured to discharge used freezing fluid from the active tip, and a vacuum insulation layer disposed around the supply conduit and the discharge conduit.

Description

Technical Field

[0001] This application claims priority based on U.S. Provisional Patent Application No. 63 / 503,773, filed on May 23, 2023, "CRYOPROBES AND RELATED METHODS", the entire disclosure of which is incorporated herein by reference.

Background Art

[0002] The present disclosure relates to cryosurgical devices, and more particularly, to cryosurgical probes having a flexible shaft connected to an active tip and related methods.

[0003] The present disclosure contemplates that cryosurgical devices, such as cryoprobes, can be used in various medical or surgical procedures. Generally, cryoprobes are used to apply extremely low temperatures to target tissues. For example, cryoprobes can be used for cryoablation or cryoanalgesia.

[0004] The present disclosure contemplates that some cryoprobes receive a supply of one or more cryogenic fluids and use this to cool tissue-contact type active parts, such as ablation tips. These cryoprobes may include a supply conduit for supplying the cryogenic fluid to the ablation tip and a discharge conduit for discharging the used cryogenic fluid from the ablation tip. Cryoprobes may have a high-pressure cryogenic fluid as a supply source. For example, there are cryoprobes that cause Joule-Thomson expansion in the vicinity of the ablation tip. In this configuration, it can receive liquid nitrous oxide at about 1200 psi and room temperature and / or discharge it as a gas or liquid-gas mixed phase flow at about 45 psi and about -90°F. For this reason, cryoprobes and related conduits and connectors are designed to withstand these pressure and temperature conditions.

Summary of the Invention

Problems to be Solved by the Invention

[0005] This disclosure assumes that while cryoprobes utilize cryogenic temperatures to achieve desired effects at a target site, exposure of other parts to cryogenic temperatures may cause undesirable effects. For example, the active tip of a cryoprobe is desirable to be extremely cold, while the shaft to which the tip is attached is desirable to remain at a temperature higher than the tissue ablation temperature. This disclosure provides a method and apparatus for cooling the active tip of a cryoprobe to a desired temperature while maintaining other external parts of the cryoprobe at a higher temperature. In this way, this disclosure provides an improvement over the prior art related to cryoprobes.

[0006] Conventional freezing devices have been used safely and effectively in cryosurgery, but further improvements to the structure and operability of the freezing probe can provide additional advantages to both the surgeon and the patient. This invention encompasses various improvements to enhance the structure, operability, and usability of the freezing probe. [Means for solving the problem]

[0007] According to a first aspect of the present invention, a freezing probe is provided. The freezing probe comprises (a) a handle, (b) a shaft located distal to the handle, the shaft including a generally rigid proximal portion and a generally flexible distal portion, and (c) an active tip located distal to the shaft, the shaft including a supply conduit for supplying freezing fluid to the active tip, a discharge conduit for discharging used freezing fluid from the active tip, and a vacuum insulation layer disposed around the supply conduit and the discharge conduit.

[0008] In a more detailed embodiment of the first embodiment, the shaft includes a shell that at least partially defines the radially outer side of the vacuum insulation layer, and the discharge conduit defines at least partially the radially inner side of the vacuum insulation layer. In a further detailed embodiment, the supply conduit, the discharge conduit, and the shell are arranged concentrically around the longitudinal axis of the shaft. In a further detailed embodiment, the freezing probe further includes a tubular thermal barrier element disposed within the vacuum insulation layer and positioned radially between the discharge conduit and the shell. In a further detailed embodiment, the thermal barrier element is composed of at least one of ceramic, foam, elastomer, composite material, and glass fiber. In a further detailed embodiment, the freezing probe further includes a distal end cap that provides a sealed connection between the shell and the discharge conduit, the distal end cap having a sealing portion, the sealing portion including an internal bore configured to receive the discharge conduit, and at least one outer surface configured to receive the shell. In a more detailed embodiment, the distal end cap is configured to engage with the active tip, the active tip having a threaded portion, and the distal end cap having a distal thread configured to screw-engage with the threaded portion of the active tip.

[0009] In a further detailed embodiment of the first embodiment, the freezing probe further comprises a proximal end cap including an extended proximal portion extending into the handle. In a further detailed embodiment, the freezing probe further comprises an adapter fluidically coupled to the proximal end cap, the adapter converting a double-tube arrangement distal to a parallel arrangement proximal to the supply conduit and the discharge conduit. In a further detailed embodiment, the freezing probe further comprises an outermost insulating cover arranged around the shell. In a further detailed embodiment, the freezing probe is used in combination with a cryosurgery module configured to supply the freezing fluid to the freezing probe or to receive used freezing fluid from the freezing probe. In a further detailed embodiment, the shaft of the freezing probe comprises at least one visible indicator configured to serve as a visual aid during operation. In a further detailed embodiment, the at least one visible indicator comprises at least one circumferential band of contrasting colors arranged on the shaft.

[0010] A second aspect of the present invention provides a method for manufacturing a vacuum insulated tube. The method includes (a) applying brazing paste to at least one joint surface of an inner tube, an outer tube, and an end cap; (b) engaging the end cap with the inner tube and the outer tube; (c) discharging the space between the inner tube and the outer tube; and (d) heating at least one of the end cap, the outer tube, and the inner tube to form sealed brazed joints between the end cap and the outer tube and between the end cap and the inner tube.

[0011] In a more detailed embodiment of the second aspect, the process further includes applying brazing paste from the outside to the interface between the outer tube and the end cap. In a further detailed embodiment, the process further includes crimping the outer tube circumferentially into the circumferential groove of the end cap. In a further detailed embodiment, the inner tube includes a straight wall section and a bellows section, and the brazed joint between the end cap and the inner tube is formed along the straight wall section. In a further detailed embodiment, the outer tube includes a straight wall section and a bellows section, and the brazed joint between the end cap and the outer tube is formed along the straight wall section. In a further detailed embodiment, the process further includes placing internal insulation material between the inner tube and the outer tube.

[0012] A third aspect of the present invention provides a freezing probe comprising (a) a handle, (b) an insulating shaft located distal to the handle, and (c) an active tip located distal to the shaft. The shaft includes, from radially outward to radially inward, an outer covering, a shell, a thermal barrier, an exhaust conduit, and a supply conduit.

[0013] In a further detailed embodiment of the third embodiment, the outer covering, the shell, the thermal barrier, the discharge conduit, and the supply conduit are arranged concentrically. In yet another detailed embodiment, the shell and the discharge conduit define at least partially a vacuum insulation jacket including the thermal barrier. In yet another detailed embodiment, the vacuum insulation jacket includes a thermal barrier material. In yet another detailed embodiment, the shaft includes a generally rigid proximal portion and a generally flexible distal portion.

[0014] A fourth aspect of the present invention provides a method for operating a cryosurgery probe. The method includes (a) bending the distal portion of the shaft of the cryosurgery probe into a desired shape; (b) bringing the active tip of the cryosurgery probe into contact with target tissue; and (c) supplying a cryogenic fluid to the active tip via the shaft while maintaining a vacuum insulation jacket along the distal portion of the shaft.

[0015] In a further detailed embodiment of the fourth aspect, the step of bending the distal portion of the shaft of a cryosurgery probe into a desired shape includes simultaneously bending the shaft shell, the shaft discharge conduit, and the shaft supply conduit into a desired shape. In yet another detailed embodiment, the step of bending the distal portion of the shaft of a cryosurgery probe into a desired shape further includes simultaneously bending a thermal barrier material positioned radially between the shell and the discharge conduit within a vacuum-insulated jacket. In yet another detailed embodiment, the shell and the discharge conduit have a bellows shape.

[0016] The descriptions of the embodiments described below should be read in conjunction with the accompanying drawings. For the sake of clarity and simplicity of illustration, please understand that the elements shown in the drawings are not necessarily drawn to scale. For example, the dimensions of one element may be exaggerated relative to others. Embodiments incorporating the teachings of this disclosure are shown and described with reference to the drawings provided herein. [Brief explanation of the drawing]

[0017] [Figure 1] This is a perspective view of a cryosurgery system according to one embodiment of the present disclosure, showing an example of a cryoprobe equipped with a flexible shaft that can be deformed into multiple shapes. [Figure 2] This is a longitudinal cross-sectional view of the freezing probe exemplified in Figure 1, along line 2-2. [Figure 3A] This is a side view of a freezing probe shaft according to one embodiment of the present disclosure. [Figure 3B] This is a cross-sectional view of the freezing probe shaft illustrated in Figure 3A, along line 3B-3B. [Figure 4] Figure 3A is a cross-sectional view of the freezing probe shaft shown along line 4-4. [Figure 5] Figure 3A is a cross-sectional view of an example of the distal end of a freezing probe shaft. [Figure 6A] This is a perspective view of the proximal end of the distal end cap of one embodiment relating to this disclosure. [Figure 6B] This is a perspective view of the distal end of the distal end cap of one embodiment relating to this disclosure. [Figure 7A] To manufacture a vacuum insulation tube according to an embodiment of the present disclosure, it is a configuration diagram showing a state where a distal end cap shown in FIG. 6A is aligned with the distal end of the discharge conduit and the shell. [Figure 7B] To manufacture a vacuum insulation tube according to an embodiment of the present disclosure, it is a configuration diagram showing a state where a distal end cap shown in FIG. 6A is attached to the distal end of the discharge conduit and the shell. [Figure 8] It is an enlarged view of the handle shown in FIG. 2 and the components housed therein. [Figure 9] It is a configuration diagram of a cryoprobe according to an embodiment of the present disclosure. [Figure 10] It is a side view of a cryoprobe shaft and a distal tip according to another embodiment of the present disclosure.

Mode for Carrying Out the Invention

[0018] Exemplary embodiments according to the present disclosure include devices, methods, and techniques related to cryosurgical devices, such as a cryosurgical probe (a "cryoprobe") in which a flexible shaft is connected to an active tip and related methods, as described and illustrated below. Of course, those skilled in the art will understand that the embodiments described below are examples and can be reconfigured without departing from the scope and spirit of the present disclosure. Also, it should be understood that modifications of exemplary embodiments that those skilled in the art can envision naturally constitute a part of the present disclosure. For clarity and accuracy, the exemplary embodiments described below may include any steps, methods, or features that those skilled in the art recognize as not essential for inclusion within the scope of the present disclosure. Unless otherwise explicitly stated, features or functions described with respect to any exemplary embodiment are also applicable to other exemplary embodiments, and repeated descriptions of similar features and functions are omitted for the sake of brevity.

[0019] Referring to Figures 1 and 2, the exemplary cryoprobe 100 may be part of a cryosurgery system 10, which may include a cryomodule 12. The cryoprobe 100 is configured to be operationally coupled to the cryomodule 12, which is configured to supply a cryofluid to the cryoprobe 100 and / or to recover the cryofluid from the cryoprobe 100, and may also provide monitoring and / or control functions. The exemplary cryomodule 12 may be substantially similar to the "cryoICE BOX" cryosurgery unit manufactured by AtriCure, Inc., located in Mason, Ohio, or may include one or more components that provide similar functions. The exemplary cryofluid may include one or more nitrous oxide, argon, carbon dioxide, and / or phase-change fluids (e.g., liquid nitrogen). In this specification, "fluid" refers to a substance in the liquid phase, gas phase, liquid-gas mixed phase, and / or supercritical phase.

[0020] In this specification, distal direction 14 and proximal direction 16 are referenced. Proximal direction 16 generally refers to the opposite side of distal direction 14. In this specification, “distal” refers to the direction generally away from the operator of the system or device (e.g., a surgeon), i.e., the direction toward the furthest end of the device that is inserted into the patient’s body. On the other hand, “proximal” refers to the direction generally toward the operator of the system or device (e.g., a surgeon), i.e., the direction away from the furthest end of the device that comes into contact with the patient’s body. However, the examples of directions referenced herein are for illustrative purposes only and should not be construed as limitations.

[0021] In the illustrated embodiment, the exemplary freezing probe 100 comprises a handle 104 which may be configured to be grasped by a user (e.g., a surgeon) or to be engaged by a robotic device (e.g., a surgical robot). More generally, the handle 104 may include any structure that can fix, hold, or manipulate the freezing probe 100 to position or restrain it in a desired location, whether or not it is used by a person (e.g., a surgeon or assistant), a robot, a mechanical device, etc. The handle 104 may be configured to connect to the freezing module 12 via one or more connecting elements 106 which may include, for example, one or more fluid conduits (e.g., for supplying and / or discharging freezing fluid) and / or one or more electrical conductors (e.g., wiring for thermocouples). The freezing probe 100 may comprise an elongated, substantially tubular shaft 108 located distal to the handle 104. An active tip 110 is positioned at the distal end 102 of the freezing probe 100, and the active tip 110 is located distal to the shaft 108. The active tip 110 is used to apply extremely low temperatures, for example, to perform cryoablation of target tissue 18.

[0022] In some exemplary embodiments, the shaft 108 may include a first proximal portion 112 and / or a second distal portion 114. In some exemplary embodiments, the proximal portion 112 of the shaft 108 may be generally rigid and / or generally elastically deformable. As used herein, “rigid” means a shaft (or part thereof) that does not deform, or deforms only slightly, under the forces applied in the normal and intended use of the device. For example, the proximal portion 112 in the embodiment shown in Figure 1 may be configured to maintain a generally linear shape and / or to return to a linear shape.

[0023] In some exemplary embodiments, the distal portion 114 of the shaft 108 may be configured to bend in one or more curved and / or planes. As used herein, “bendable” means a shaft (or part thereof) that is capable of undergoing elastic and / or plastic deformation due to forces applied during the normal and intended use of the device. For example, a bendable shaft (or part thereof) may be flexible or malleable. As used herein, “flexible” means a shaft (or part thereof) that deforms primarily elastically due to forces applied during the normal and intended use of the device and returns to approximately its original shape when the stress is removed. As used herein, “malleable” means a shaft (or part thereof) that can be bent into a desired shape due to forces applied during the normal and intended use of the device and retains that shape approximately after the stress is removed. In some exemplary embodiments, the shaft may be configured to be bent manually (e.g., without tools). In other exemplary embodiments, the shaft may be configured to be bent using a tool, such as a manual tube bender.

[0024] In some exemplary embodiments, the distal portion 114 and / or proximal portion 112 of the shaft 108 may be configured to have greater rigidity than the corresponding portion of a similar device. Thus, these embodiments according to at least some aspects of the present disclosure may be usable at more extreme angles and / or more difficult insertion angles associated with complex surgical procedures compared to similar devices.

[0025] In some exemplary embodiments, the distal portion 114 of the shaft 108 may be configured to bend at an angle 116 with respect to the longitudinal axis A of the shaft 108 and / or the proximal portion 112 of the shaft 108. For example, the distal portion 114 of the shaft 108 may be bendable to approximately 180 degrees. As shown by the dashed arrows in Figure 1, the distal portion 114 of the shaft 108 can be bent in any plane that is substantially parallel to the longitudinal axis A. In some embodiments, as shown by the dashed arrows in Figure 1, the distal portion 114 of the shaft 108 may be bendable in multiple planes. For example, the distal portion 114 of the shaft 108 can be bent not only in a plane substantially parallel to the longitudinal axis A of the shaft 108 (e.g., upward), but also in a plane that is oblique to the longitudinal axis A (e.g., to the left). As used herein, “obliquely” means an angle that is neither perpendicular nor parallel. In such embodiments, the distal portion 114 of the shaft may be bent in a plane that is substantially perpendicular to the longitudinal axis A of the shaft 108, and / or in a plane that is inclined with respect to the longitudinal axis A. Furthermore, in some embodiments, the distal portion 114 of the shaft 108 may be bent into two or more curved shapes in the same plane or in different planes, for example, by curving upward and downward (or left and right) to form a generally S-shape.

[0026] In the exemplary embodiment shown in Figure 1, the shaft 108 includes a generally rigid portion 112 and a generally flexible portion 114. However, in various other exemplary embodiments, the shaft may include one or more generally flexible portions only, or one or more generally rigid portions only, and / or a shaft including any combination of one or more generally flexible portions and one or more generally rigid portions in any arrangement. In the illustrated embodiment, the generally rigid portion 112 is generally straight, but in other embodiments, it may include one or more curves formed to the left, right, up, and / or down as viewed from the user. In the illustrated embodiment, the generally rigid portion 112 is fixed to the handle 104 and configured not to rotate relative to the handle. However, in another exemplary embodiment, the generally rigid portion 112 may be configured to rotate relative to the handle 104.

[0027] Referring to Figures 1 to 5, in some exemplary embodiments, the shaft 108 may include one or more internal conduits (for example, these may define at least partially corresponding lumens and / or flow paths) configured to guide the freezing fluid to and / or from the handle 104. And / or, the shaft 108 may include one or more electrical conductors extending to and / or from the active tip 110 and / or the handle 104. For example, the shaft 108 may include a supply conduit 118 configured to transport the freezing fluid from the handle 104 to the active tip 110, a discharge conduit 120 configured to transport the used freezing fluid from the active tip 110, and one or more wires 119 connected to a thermocouple 121. In the illustrated embodiment, the supply conduit 118 is made of stainless steel (e.g., 304 / 304L stainless steel, hard-heat treated) and the discharge conduit 120 is also made of stainless steel, but different materials may be used in other embodiments. The thermocouple 121 is configured to detect temperature during the operation of the apparatus and can, for example, measure the temperature of the distal end 102 of the freezing probe 100. In the illustrated embodiment, the thermocouple 121 is positioned closer to the active tip 110 than similar freezing probes and provides more relevant temperature information than other freezing probes. As used herein, “used freezing fluid” refers to the freezing fluid discharged from the active tip 110 (for example into the discharge conduit 120), regardless of its phase, temperature, or pressure, and regardless of whether it still has cooling capacity.

[0028] In the illustrated embodiment, the supply conduit 118 may be arranged substantially concentrically within the discharge conduit 120. In this specification, “concentric” refers to components arranged to have a common center point and / or axis (e.g., longitudinal axis A). In the illustrated embodiment, the freezing fluid flowing into the active tip 110 flows through the inside of the supply conduit 118, and the used freezing fluid flowing out of the active tip 110 flows through an annular lumen located outside the supply conduit 118 within the discharge conduit 120. The supply conduit 118 and / or the discharge conduit 120 may also be arranged substantially concentrically within other components of the shaft 108. In another embodiment, the conduits 118 and 120 may be arranged parallel to each other (i.e., substantially parallel), or non-concentrically, and further non-concentrically within the shaft 108.

[0029] Referring to Figure 5, in some exemplary embodiments, the active tip 110 may include a wall 122 that at least partially defines an internal cavity 124 having a closed distal end. In the illustrated embodiment, the active tip 110 is made of aluminum having a relatively high thermal conductivity. In another embodiment, the tip 110 may be made of other suitable material such as stainless steel. Those skilled in the art will understand that when using alternative materials with different thermal conductivity, it may be necessary to modify parts of the design of the tip 110, such as the thickness of the wall 122, to obtain the desired thermal performance. The wall 122 may at least partially define a generally rounded outer shape, or it may have any desired shape for engagement with a target anatomical structure. For example, the active tip 110 may have a generally bulbous tissue contact surface 126 with a diameter 166 of about 8 mm. In this specification, “bulbous” means a generally rounded outer surface that is enlarged in diameter (compared to an adjacent structure). Other external shapes and surface shapes, though not limited to these, include dome-shaped cylindrical surfaces, rounded conical surfaces, or various other bulging surfaces well known to those skilled in the art, which can be applied to the active tip 110.

[0030] In the illustrated embodiment, the active tip 110 may include a nozzle 128 (e.g., an opening) through which the frozen fluid from the supply conduit 118 flows into the internal cavity 124. The internal cavity 124 may be fluidically connected to the discharge conduit 120. Thus, the internal cavity 124 of the active tip 110 is fluidically interposed between the supply conduit 118 and the discharge conduit 120.

[0031] During operation, the freezing fluid supplied from the freezing module 12 flows into the internal cavity 124 of the active tip 110 through the supply conduit 118 and nozzle 128. Generally, the freezing fluid passing through the nozzle 128 is at a high pressure upstream of the nozzle 128 and is reduced to a significantly lower pressure in the cavity 124 downstream, causing Joule-Thomson expansion and a significant decrease in the temperature of the freezing fluid and the active tip 110. In some exemplary embodiments, when nitrous oxide is used as the freezing fluid, the nitrous oxide is supplied as a liquid at approximately 27°C and 800 psi upstream of the nozzle 128, forming a gas phase or gas-liquid mixed phase at approximately 45 psi and -68°C in the internal cavity 124 of the active tip 110. Alternatively, the freezing fluid may be supplied as a supercritical fluid. As Joule-Thomson expansion continues within the active tip 110, the wall 122 is cooled to a level suitable for use in cryosurgery procedures (e.g., cryocautery). For example, the procedure can be performed by bringing the active tip 110 into contact with the tissue to be cauterized. Depending on the type and state of the freezing fluid used, the typical flow rate of the freezing fluid passing through the nozzle 128 may range from approximately 15 cubic centimeters per minute to over 100 cubic centimeters per minute.

[0032] This disclosure assumes that during the operation of the freezing probe 100, the freezing fluid supplied to the active tip 110 and / or discharged from the active tip 110 may cool the shaft 108. Depending on the circumstances, the freezing fluid flowing through the shaft 108 may become sufficiently cold, potentially causing undesirable thermal effects such as freezing of non-target tissue or adhesion of the shaft 108 to non-target tissue. For example, in procedures performed in the pleural cavity, it is desirable to avoid accidentally freezing or adhering to lung tissue or the periphery of chest wall openings. Therefore, in the illustrated embodiment, the shaft 108 is provided with a radially interposed thermal insulation section 130 between the freezing fluid conduits 118, 120 and the outer surface 132 of the shaft 108. In some exemplary embodiments, the shaft 108 is configured to exhibit higher thermal insulation performance than corresponding parts of a similar device, thereby providing operational advantages.

[0033] In the illustrated embodiment, the insulation section 130 may include a vacuum insulating layer 134 located radially outside the discharge conduit 120. In this specification, “vacuum insulating layer” refers to a space that is at least partially depressurized and configured to reduce heat transfer, including quasi-vacuum, partial vacuum, and complete vacuum. In the illustrated embodiment, the vacuum insulating layer 134 constitutes a generally annular depressurized space at least partially enclosed by the outer surface of the discharge conduit 120 and the inner surface of the shell 136 of the shaft 108. In the illustrated embodiment, the shell 136 is made of stainless steel, but other materials may be used in other embodiments. Furthermore, in the illustrated embodiment, the shell 136 is at least partially covered by an outer covering 138, which may be a heat-shrinkable polymer tube or the like, located radially outside the shell 136.

[0034] In the illustrated embodiment, the thermal barrier element 140 is located within the vacuum insulation layer 134, for example, radially between the exhaust conduit 120 and the shell 136. For example, the thermal barrier element 140 may be made of a generally tubular woven ceramic material. In another embodiment, the thermal barrier element 140 may be made of other insulating material that can withstand both cryogenic and brazing temperatures, such as glass fiber, elastomer, foam, silicon, carbon fiber, composite material, etc. In other embodiments without vacuum insulation, or if the sealing of the reduced-pressure space is compromised in the illustrated embodiment, the thermal barrier element 140 may be configured to provide sufficient insulating performance to meet desired performance requirements with respect to shaft temperature.

[0035] In the illustrated embodiment, the shaft 108 employs a generally smooth straight-walled structure in the proximal portion 112 and a generally bellows-like structure in the distal portion 114, thereby obtaining the desired rigidity in the proximal portion 112 and the desired flexibility in the distal portion 114. In this specification, "convoluted" refers to a structure having an irregular shape or form, which may be curved or bent, and which includes corrugated or bellows-like irregularities, regardless of whether it is helical or not. In particular, in this embodiment, in the proximal portion 112, the supply conduit 118, the discharge conduit 120, and the shell 136 are all formed as generally smooth straight-walled (i.e., non-bellows-like) tubes. On the other hand, in the distal portion 114, the discharge conduit 120 and the shell 136 are each formed as generally bellows-like tubes. In the illustrated embodiment, these bellows structures are helical and / or spiral in shape, but in other embodiments, other forms of bellows structures, such as circumferential corrugations, may be employed. In some exemplary embodiments, one or more wires 119 connected to the thermocouple 121 may be routed in a generally helical manner along the distal bellows section 114 of the shaft 108, or wound, for example, along a helical groove within the bellows section 114. In some alternative embodiments, the supply conduit 118, the discharge conduit 120, and / or the shell 136 may include a bellows structure within the generally rigid proximal section 112 of the shaft 108.

[0036] Referring to Figure 4, in the illustrated embodiment, the proximal portion 112 of the shaft 108 may be provided with, from outside to inside, one or more of the following components, namely, an outer covering 138, a shell 136 (e.g., a straight-walled structure), a thermal barrier 140, a discharge conduit 120 (e.g., a straight-walled structure), and / or a supply conduit 118 (e.g., a straight-walled structure).

[0037] Referring to Figure 5, in the illustrated embodiment, the distal portion 114 of the shaft 108 may be provided with, from outside to inside, one or more of the following components, namely, an outer covering 138, a shell 136 (e.g., a bellows-like structure), a thermal barrier 140, a discharge conduit 120 (e.g., a bellows-like structure), and / or a supply conduit 118 (e.g., a straight-walled structure).

[0038] Referring to Figures 5, 6A, 6B, 7A, and 7B, in the illustrated embodiment, the distal end 142 of the discharge conduit 120 (which may have a straight wall structure) and the distal end 144 of the shell 136 (which may also have a straight wall structure) are joined to the proximal sealing portion 202 of the distal end cap 200, at least partially sealing the vacuum insulation layer 134. The distal end 204 of the distal end cap 200 is provided with an internally threaded recess 206 configured to engage with the externally threaded proximal end 146 of the active tip 110.

[0039] In the illustrated embodiment, the distal end cap 200 is made of stainless steel. In some embodiments, the threaded connection between the threaded proximal end 146 of the active tip 110 and the internally threaded recess 206 of the distal end cap 200 may be sealed with epoxy resin 148. This is particularly useful when the active tip 110 and the distal end cap 200 are made of different materials (e.g., aluminum and stainless steel, respectively). In another embodiment, instead of epoxy resin 148, a suitable alternative thread sealant (e.g., thread sealing tape [e.g., PTFE], biocompatible room-temperature curing silicone elastomer, etc.) may be used. In yet another embodiment, the joint may be sealed with a suitable gasket and / or O-ring made of a material that can withstand the low temperatures associated with cryosurgery. If the distal end cap 200 and the active tip 110 are made of the same or compatible materials, other joining methods such as welding and brazing may be used.

[0040] In the illustrated embodiment, the proximal sealing portion 202 of the distal end cap 200 includes an inner bore 220 configured to receive the distal end 142 of the discharge conduit 120 in a sealed state. The proximal sealing portion 202 of the distal end cap 200 is configured to be inserted in a sealed state into the distal end 144 of the shell 136. For example, the distal end 142 of the discharge conduit 120 and / or the distal end 144 of the shell 136 may be sealed to the proximal sealing portion 202 of the distal end cap 200 by brazing.

[0041] In the illustrated embodiment, the proximal sealing portion 202 of the distal end cap 200 comprises two circumferential surfaces 208 and 210 separated by a circumferential groove 212. The circumferential surfaces 208 and 210 are configured to engage with the radial inner surface of the distal end portion 144 of the shell 136. The groove 212 may be configured to engage with the shell 136, for example, when the shell 136 is crimped and fixed to the proximal sealing portion 202 of the distal end cap 200.

[0042] Referring again to Figures 5, 6A, 6B, 7A, and 7B, an example of a method for manufacturing a vacuum-insulated tube used in a freezing probe or the like may include the steps of preparing an inner tube (e.g., discharge conduit 120), an outer tube (e.g., shell 136), an end cap (e.g., distal end cap 200), and / or an internal insulating material (e.g., thermal barrier 140). The step of preparing the inner tube 120 may include the step of forming a tube having a straight wall section and a bellows section, and / or the step of preparing the outer tube 136 may include the step of forming a tube having a straight wall section and a bellows section. This method may also include the step of placing the internal insulating material 140 between the inner tube 120 and the outer tube 136. For example, the internal insulating material 140 may be placed on the outer circumference of the inner tube 120, and then the inner tube 120 and the internal insulating material 140 may be inserted into the outer tube 136. Furthermore, the method may include a step of applying a brazing paste 214 to form a brazed joint between the end cap 200 and one or more tubes 120, 136. For example, the brazing paste 214 may be applied to the inner bore 220 and / or the joint surfaces of the inner tube 120, outer tube 136, and end cap 200. The method may also include a step of engaging the end cap 200 with the inner tube 120 and / or outer tube 136. In the illustrated embodiment, the method may include a step of crimping the outer tube 136 to the end cap 200 using one or more crimping tools 216, 218. For example, the outer tube 136 may be crimped in a generally circumferential direction into the circumferential groove 212 of the distal end cap 200. In some embodiments, the brazing paste 214 may be applied to the outside, for example, to the interface between the distal end of the outer tube 136 and the end cap 200. Although this exemplary method has been described with respect to the distal member of the insulating tube, a proximal end cap can also be attached to the other end (i.e., the proximal end) of the insulating tube by performing a similar operation. The method may also include a step of heating the assembly in a vacuum furnace or the like to form a brazed joint. Before and / or during heating, the pressure inside the furnace may be reduced to remove the reduced pressure space that constitutes the vacuum insulating layer 134.

[0043] Referring to Figures 5, 6A, 6B, 7A, 7B, and 8, the proximal end of the vacuum insulation layer 134 may be sealed by a proximal end cap 250 having a configuration substantially similar to that of the distal end cap 200. For example, the proximal end cap 250 may have a distal end sealing portion 252 having a configuration corresponding to the proximal sealing portion 202 of the distal end cap 200. Similarly, the proximal end cap 250 may be positioned on the discharge conduit 120 and the shell 136 in substantially the same manner as described above with respect to the distal end cap 200.

[0044] In the illustrated embodiment, the proximal end cap 250 includes an extended proximal portion 254, which may be connected to the adapter assembly 256 in a sealed manner, extending proximal. The adapter assembly 256 may be configured to convert the double-pipe (i.e., concentric) structure of the supply conduit 118 and discharge conduit 120 in the shaft 108 to a parallel structure of the supply-side connecting element 106A and the discharge-side connecting element 106B that constitute the connecting element 106.

[0045] In the illustrated embodiment, the adapter assembly 256 comprises an adapter body 258, a compression joint 260 positioned distal to the adapter body 258 and configured to engage in a sealed manner with the extended proximal portion 254 of the proximal end cap 250, a supply interface 262, and a discharge interface 264. The compression joint 260 includes a two-piece ferrule 266 (e.g., a cooperating front ferrule and a rear ferrule) positioned around the extended proximal portion 254 of the proximal end cap 250, and an internally threaded nut 268 configured to screw-engage with the distal external thread 270 of the adapter body 258. By tightening the nut 268 onto the adapter body 258, the ferrule 266 forms a sealed connection between the extended proximal portion 254 of the proximal end cap 250 and the adapter body 258.

[0046] In the illustrated embodiment, the supply interface 262 extends through the adapter body 258 and constitutes a proximal extension of a supply conduit 118 that is sealed to it. In the illustrated embodiment, the supply conduit 118 is sealed to the adapter body 258 by brazing. In some embodiments, the supply conduit 118 may be spot-welded to the adapter body 258, for example, before the brazing process. The proximal end of the supply interface 262 is provided with a barbed fitting 272 (or other suitable fitting) configured to engage in a sealed manner with a supply-side connecting element 106A (e.g., a hose), which may be connected, for example, using a crimp sleeve. In the illustrated embodiment, the discharge interface 264 includes a proximal barbed fitting 274 (or other suitable fitting) configured to engage in a sealed manner with a discharge-side connecting element 106B (e.g., a hose), which may similarly be connected using a crimp sleeve or the like. The thermocouple wire 119 (or its extension) may be routed through the handle 104 to the connecting element 106.

[0047] Referring to Figures 1, 2, and 8, in some exemplary embodiments, one or more additional thermal barriers may be provided in areas where surfaces that come into contact with a patient or operator may become excessively cool. For example, under certain operating conditions, the distal portion of the handle 104 (i.e., near the proximal end of the shaft 108) may become cold for extended periods, reaching an uncomfortable temperature for the operator. Therefore, in the illustrated embodiment, the handle 104 is provided with a distally extending, generally conical nose guard 150 positioned around the proximal portion of the shaft 108. In some embodiments, an additional thermal barrier 152, generally annular in shape, may be positioned around the shaft 108 and / or within the nose cone 150. Also in some exemplary embodiments, part or all of the nose cone 150 may be configured with a visually distinguishable appearance color (or other identifying marking) from the handle 104 to indicate to the operator that contact with the nose cone 150 should be restricted.

[0048] Referring to Figures 1, 8, and 9, in the illustrated embodiment, the freezing probe 100 is provided with various proximal connectors for detachably connecting the connecting element 106 to the freezing module 12. For example, the freezing probe 100 may include a supply connector 154 (for connecting the supply-side connecting element 106A to the freezing module 12), a discharge connector 156 (for connecting the discharge-side connecting element 106B to the freezing module 12), and / or one or more thermocouple connectors 158, 160 (for connecting one or more thermocouple wires 119 to the freezing module 12).

[0049] Referring to Figures 1 and 9, the shaft 108 may be provided with at least one visible indicator configured to serve as a visual aid for the operator. For example, in the illustrated embodiment, a visually contrasting circumferential band 162 is provided at a position 164 axially from the tip of the active tip 110 on the shaft 108. In some embodiments, the axial distance 164 is, for example, about 4 cm. Such a visual indicator can be used as a guide for the operator to properly position the active tip 110 relative to visible anatomical structures and / or to prevent unintended cooling of surrounding tissues.

[0050] Referring to Figure 10, another exemplary cryoprobe 300 may be substantially similar to cryoprobe 100, containing similar components and configured and used in a similar manner. Descriptions of the corresponding structures and operations are omitted to avoid redundancy. In cryoprobe 300, the distal portion 302 may include an active tip 310. The active tip 310 may have a generally bulging tissue contact surface 326. Referring to Figures 5 and 10, the active tip 110 of cryoprobe 100 has a diameter 166 of approximately 8 mm, while the active tip 310 of cryoprobe 300 has a diameter 366 of approximately 10 mm. Other embodiments may include active tips having other suitable diameters and bulging shapes.

[0051] One example of how to operate the freezing probes 100 and 300 may include first bending the distal portions 114 and 302 of the shaft 108 into a desired shape, then connecting the freezing probes 100 and 300 to the freezing module 12, bringing the active tips 110 and 310 into contact with the target tissue 18, and / or further supplying and / or discharging freezing fluid to the active tips 110 and 310 to cool them. The bending operation may include simultaneously bending one or more components of the shaft (e.g., the outer covering 138, the shell 136, the thermal barrier 140, the discharge conduit 120, and / or the supply conduit 118). Furthermore, a thawing step of the active tips 110 and 310 may be performed, and / or each of the above steps may be repeated at the same or different locations.

[0052] Examples of prior art documents related to the present invention include the following U.S. patents and patent publications, the contents of which are incorporated herein by reference in their entirety. U.S. Patent No. 8,915,908 (published December 23, 2014), U.S. Patent Publication No. 2020 / 0085485 (published March 19, 2020), U.S. Patent No. 11,179,185 (published November 23, 2021), U.S. Patent Publication No. 2023 / 0061212 (published March 2, 2023), U.S. Patent Publication No. 2023 / 0067890 (published March 2, 2023), and U.S. Patent Publication No. 2023 / 0063557 (published March 2, 2023). Features and improvements in the embodiments described in these documents can be used in combination with embodiments of the present invention, and conversely, features, elements and methods described in the present invention can be applied to embodiments in these documents.

[0053] From the above description and summary of the invention, it will be apparent to those skilled in the art that the methods and apparatus described herein constitute exemplary embodiments of the disclosure, but the scope of the disclosure is not limited to these specific configurations, and modifications can be made without departing from the scope defined by the following claims. Similarly, it will be understood that, because implicit and / or unexpected advantages may exist even if not explicitly discussed herein, it is not necessary to satisfy any or all of the effects or purposes specified herein in order to be included in the scope of the claims.

Claims

1. The handlebars and A shaft located distal to the handle, comprising a generally rigid proximal portion and a generally flexible distal portion, The shaft comprises an active tip positioned distal to the shaft, The shaft includes a supply conduit configured to supply freezing fluid to the active tip, a discharge conduit configured to discharge used freezing fluid from the active tip, and a vacuum insulation layer disposed around the supply conduit and the discharge conduit. Freezing probe.

2. The shaft includes a shell that at least partially defines the radially outer side of the vacuum insulation layer, The discharge conduit defines at least partially the radially inward side of the vacuum insulation layer. The freezing probe according to claim 1.

3. The supply conduit, the discharge conduit, and the shell are arranged concentrically around the longitudinal axis of the shaft. The freezing probe according to claim 2.

4. The system further comprises a tubular thermal barrier element disposed within the vacuum insulation layer and positioned radially between the discharge conduit and the shell, The freezing probe according to claim 2.

5. The thermal barrier element is composed of at least one of ceramic, glass fiber, elastomer, foam, silicon, carbon fiber, and composite material. The freezing probe according to claim 4.

6. The freezing probe further comprises a distal end cap that provides a sealed connection between the shell and the discharge conduit, The distal end cap includes a sealing portion, The aforementioned sealing portion is An internal bore configured to receive the aforementioned discharge conduit, Including at least one outer surface configured to receive the shell, The freezing probe according to claim 2.

7. The distal end cap is configured to engage with the active tip, The active tip includes a threaded portion, The distal end cap includes a distal thread configured to screw-engage with the threaded portion of the active tip, The freezing probe according to claim 6.

8. The distal end cap is configured to engage with the active tip, The active tip and the distal end cap are sealed together using at least one of a welding filler, solder, or brazing material. The freezing probe according to claim 6.

9. The freezing probe according to claim 2, further comprising a proximal end cap including an extended proximal portion extending within the handle.

10. The freezing probe further comprises an adapter fluidly connected to the proximal end cap, The freezing probe according to claim 9, wherein the adapter converts the double-tube arrangement on the distal side of the supply conduit and the discharge conduit to a parallel arrangement on the proximal side.

11. The freezing probe according to claim 2, further comprising an outermost insulating cover positioned around the shell.

12. The freezing probe according to claim 1, A cryosurgery system comprising: a cryosurgery module configured to supply the freezing fluid to the freezing probe or to receive the used freezing fluid from the freezing probe.

13. The freezing probe according to claim 1, wherein the shaft includes at least one visible indicator configured to function as a visual aid during operation.

14. The freezing probe according to claim 1, wherein the at least one visible display includes at least one circumferential band of contrasting colors arranged on the shaft.

15. A method for constructing a vacuum-insulated tube, A step of applying brazing paste to at least one joint surface of the inner tube, outer tube, and end cap, The steps include engaging the end cap with the inner tube and the outer tube, A step of discharging the space between the inner tube and the outer tube, A step of heating at least one of the end cap, the outer tube, and the inner tube in order to form a sealed brazed joint between the end cap and the outer tube, and between the end cap and the inner tube, Methods that include...

16. The process further includes applying brazing paste from the outside to the interface between the outer tube and the end cap. The method according to claim 15.

17. The process further includes crimping the outer tube circumferentially into the circumferential groove of the end cap. The method according to claim 15.

18. The inner tube includes a straight wall section and a bellows section, The brazed joint between the end cap and the inner tube is formed along the straight wall portion. The method according to claim 15.

19. The outer tube includes a straight wall section and a bellows section, The brazed joint between the end cap and the outer tube is formed along the straight wall portion. The method according to claim 15.

20. The process further includes placing an internal insulating material between the inner tube and the outer tube. The method according to claim 15.

21. The handlebars and An insulating shaft positioned distal to the handle, The shaft comprises an active tip positioned distal to the shaft, A freezing probe comprising a shaft extending radially from the outside to the inside, including an outer covering, a shell, a thermal barrier, an exhaust conduit, and a supply conduit.

22. The outer covering, the shell, the thermal barrier, the discharge conduit, and the supply conduit are arranged concentrically. The freezing probe according to claim 21.

23. The shell and the discharge conduit define at least partially the vacuum insulation jacket including the thermal barrier. The freezing probe according to claim 21.

24. The vacuum insulation jacket includes a thermal barrier material. The freezing probe according to claim 23.

25. The shaft includes a proximal portion that is generally rigid and a distal portion that is generally flexible. The freezing probe according to claim 21.

26. A method for operating a cryosurgery probe, The process of bending the distal end of the shaft of the cryosurgery probe into a desired shape, The steps include bringing the active tip of the cryosurgery probe into contact with the target tissue, A step of supplying a freezing fluid to the active tip via the shaft while maintaining a vacuum insulation jacket along the distal portion of the shaft, Methods that include...

27. The step of bending the distal portion of the shaft of the cryosurgery probe into a desired shape includes the step of simultaneously bending the shell of the shaft, the discharge conduit of the shaft, and the supply conduit of the shaft into a desired shape. The method according to claim 26.

28. The step of bending the distal portion of the shaft of the cryosurgery probe into a desired shape further includes the step of simultaneously bending a thermal barrier material positioned radially between the shell and the discharge conduit within the vacuum insulation jacket. The method according to claim 27.

29. The shell and the discharge conduit have a bellows shape. The method according to claim 27.

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