JP2015500675A - Closed loop cryosurgical pressure and flow control system - Google Patents

Abstract

A system for supplying phase-shifting coolant to a surgical device, the first reservoir of liquid-phase coolant and a liquid supply conduit leading to coolant transfer from the reservoir to the surgical device A second reservoir of gas phase coolant, a gas supply conduit through which coolant travels from the second reservoir to the surgical device, and coolant discharged from the surgical device A backflow conduit that backflows to the first and / or second reservoir; a coolant backflow control unit that controls the backflow of coolant via the backflow path and includes a pump; and a first pressure sensor; A second pressure sensor; and a pressure regulator for adjusting the pressure of the first reservoir based on information from the pressure sensor. [Selection] Figure 1

Description

  Embodiments of the present invention relate to cooling flow regulation systems, and more specifically to devices and systems for regulating pressure in a closed loop where pressure is at least partially regulated through flow regulation through the system.

  Various cryosurgical systems that control coolant pressure are known. Furthermore, various approaches to adjusting the cooling pressure are known. Examples include US Patent Publication Nos. 2009/0270851 and 2007/0149957, and subsequent US Patent Nos. 5,520,682, 7,192,426, and 5,334,181. It is out. However, the known systems and approaches have not been totally successful in providing stable and smooth pressure regulation.

  The background art does not provide smooth and stable pressure regulation.

  The present invention, in at least some embodiments, provides a cryosurgical system and device that exhibits smooth and consistent pressure regulation while pressure is at least partially regulated through flow regulation. It has made more progress than

  One aspect of the present invention provides a system for selectively cooling and warming the tip of a cryosurgical instrument using a dual phase coolant. The system includes two sources of the coolant, a first source for storing the liquid phase coolant, and at least part of the liquid phase coolant stored therein is gas phased A first source having therein a first source heater that heats the liquid phase coolant to convert the coolant to a second source that stores the coolant in a gas phase; A first delivery path between a first source and the tip; a second delivery path between the second source and the tip; and selective coolant from the respective source to the tip. A coolant delivery control unit for delivering to the coolant, a coolant reverse flow path from the tip to the first and second sources, and a reverse flow of the coolant via the coolant reverse flow path. A coolant backflow control unit including a pump for pumping coolant to the second source; A first pressure sensor for sensing pressure in the first source, a second pressure sensor for sensing pressure in the second source, and the first source based on information from the pressure sensor. And a pressure controller including a pressure controller for adjusting the pressure.

  Another aspect of the invention is an apparatus for delivering a phase-shifting coolant to a surgical device, the first reservoir of the liquid phase coolant and the surgical device from the first reservoir A liquid supply conduit leading to the transition of the coolant into the gas phase, a second reservoir of the gas phase coolant, and a gas supply conduit leading to the transition of the coolant from the second reservoir to the surgical device A reverse flow conduit in which the discharged coolant from the surgical device flows back to the first and / or second reservoir while the discharged coolant is in the gas phase; and in the reverse flow path Based on information from the pressure sensor and flow meter, the pump selectively pumping the back-flowing coolant into the first reservoir and / or the second reservoir Selectively Energized to including, a logic section which controls the total pressure in the system, it provides an apparatus.

  Yet another aspect of the present invention provides a first coolant comprising: (i) a liquid coolant delivery path; and (ii) a liquid coolant reservoir in fluid communication with the cryosurgical device via a coolant reverse flow path. A delivery loop; (ii) the cryosurgical device via a gas coolant delivery path; and (ii) a gas coolant containment that is in gas communication with the liquid coolant containment via a portion of the coolant reverse flow path. And a second coolant delivery loop including the system. The coolant delivery path delivers the exhausted gaseous coolant from the cryosurgical device to the first and / or second coolant storage while selectively heating the exhausted gas coolant. A heater for maintaining the temperature of the coolant so as to exceed the boiling temperature of the coolant, and a pump for selectively increasing the local pressure in the coolant reverse flow path. When the liquid coolant heater is energized, the liquid coolant inside the liquid coolant storage unit is converted to a gas state and delivered to the second coolant storage unit.

  Yet another aspect of the present invention is a system for selectively cooling and warming the tip of a cryosurgical instrument using a dual phase coolant, wherein the two sources of coolant, liquid The liquid phase coolant is a first source for storing the phase coolant and converts at least a portion of the liquid coolant stored therein to a gas phase coolant And a first source between the first source and the tip, the first source having a first source heater for heating the coolant, and a second source for storing the gas phase coolant. A gas phase coolant that is a second delivery path between the supply path, the second source, and the tip, and that moves from the second source to the tip in the second delivery path. Including a gas phase coolant heater to heat, and cooling from each source to the tip A coolant delivery control unit for selectively delivering the coolant, a coolant reverse flow path from the tip to the first and second sources, and a control of the coolant reverse flow via the coolant reverse flow path A coolant heater for selectively heating the coolant inside the coolant reverse flow path and maintaining the coolant above the boiling temperature, and a flow rate for measuring the flow rate of the coolant in the reverse flow A coolant back flow control unit, a first pressure sensor for sensing pressure in the first source, and a first pressure sensor that includes a meter and a pump for pumping the coolant in the back flow to the second source, A pressure controller that includes a second pressure sensor that senses pressure in a second source and a pressure regulator that adjusts the total pressure of the system based on information from the pressure sensor and the flow meter. Provide the system.

  Yet another aspect of the present invention provides a system for selectively cooling and warming the tip of a cryosurgical instrument using a dual phase coolant. The system includes two sources of the coolant, a first source for storing a liquid phase coolant, the container being completely contained within the first source, and the container being in a liquid phase Containing the coolant, the container is in fluid communication with the first source through a check valve, and when the pressure in the first source is greater than in the container, the check valve is opened to A first source between the first source and the tip, wherein the liquid source coolant flows from the first source to the vessel, as well as a second source for storing a vapor phase coolant. A delivery path, a second delivery path between the second source and the tip, a coolant delivery controller for selectively delivering coolant from the respective source to the tip, and from the tip Via the coolant reverse flow path to the first and second sources and the coolant reverse flow path A coolant back flow control unit including a pump for controlling the coolant back flow while pumping the coolant in the back flow to the second source, and a first pressure sensing the pressure in the first source. A pressure controller comprising: a sensor; a second pressure sensor that senses pressure in the second source; and a pressure regulator that adjusts the total pressure of the system based on information from each pressure sensor; including.

  The term “cryoprobe” as used herein is given as a non-limiting example of a cryosurgical instrument. Also, although embodiments and / or aspects of the present invention are described in the context of a cryoprobe, it should be understood that other cryosurgical instruments are also contemplated and intended to be included.

  If you do not want to be limited in any way, and do not want to give a closed list, the invention in at least some embodiments effectively adjusts the “two phase flow” The level of heat flux is controlled by the flow of the coolant and boiling.

  These and / or other aspects and / or advantages of the present invention are set forth in the detailed description that follows, and can be inferred from this detailed description, and / or by practice of the invention. It is possible to learn.

The invention will be more readily understood from the detailed description of the embodiments of the invention made in accordance with the following accompanying drawings.
1 shows a closed loop system 100 adapted for one embodiment of the present invention. Fig. 5 shows a closed loop system 200 adapted to an embodiment of the invention featuring a pump that operates stably. Fig. 5 shows a closed loop system 300 adapted to an embodiment of the present invention featuring an additional structure for generating a gaseous coolant. FIG. 6 shows a partial view of a closed loop system 400 adapted to an embodiment of the present invention featuring an additional pressure control structure.

  Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals are used to refer to like elements throughout. These embodiments are described below to illustrate the present invention by referring to the drawings. Referring now in particular to the detailed drawings, the matter illustrated is by way of example only and is for purposes of illustration only of a preferred embodiment of the present invention. It is emphasized that the principles and conceptual aspects of the invention are presented for reasons of explanation that are readily understood. In this regard, there is no intention to present structural details of the invention in more detail than is necessary for a basic understanding of the invention, and the description will show how multiple aspects of the invention can be implemented. This is done in accordance with the drawings that will be revealed to the contractor.

  Before describing exemplary embodiments of the invention, the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The invention may be practiced or carried out in various ways in various ways. Also, it is to be understood that the wording and terms used herein are for purposes of explanation and should not be considered limiting.

  Referring now to FIG. 1, a closed loop system 100 for recycling a gaseous coolant in a pressurized manner is shown in which the pressure and flow within the system is adjusted. The system 100 includes a liquid coolant source 104, a gas coolant source 102, a cryoprobe 117, and a structure that provides various coolant flow paths, described in detail below.

  The liquid coolant source 104 is connected to the cryoprobe 117 via a line 118, a two-way valve 121, and a cryoprobe inlet 116 in series from upstream to downstream.

  The gas coolant source 102 is connected to the cryoprobe 117 via the line 110, the two-way valve 113, the line 115, the two-way valve 112, the heater 105, and the cryoprobe inlet 108 in series from upstream to downstream. Yes.

  The cryoprobe 117 is a gas coolant via a line 119, a two-way valve 120, a line 123, a heater 122, a line 114, and a pump 134, a line 132, and the two-way valve 106 in series from upstream to downstream. Connected to source 102. The flow meter 182 and the safety valve 107 may be connected to the line 124 between the heater 122 and the pump 134.

  The cryoprobe 117 is connected via a line 133, two-way valves 130 and 130, a line 129, and a pressure indicator 181 connected in series to a line 132 at a point between the pump 134 and the two-way valve 106. Connected to the liquid coolant source 104.

  Also present in the system 100 is a pressure regulator connected to a line 135 that interconnects the two-way valve 130 and the line 115.

  The cryoablation procedure may include one or more AC cooling and thawing process activation following the initialization procedure.

  The operation of the system 100 will be described. During the freezing process of cryoablation, liquid coolant is present from the source 104 through line 118. Although the flow is controlled by either the pressure regulator 101 or the two-way valve 121, the two-way valve 121 is normally in an open state during the refrigeration process. The flow of the liquid coolant is controlled as the liquid coolant boils, thereby restricting the heat flux and ensuring a smooth operation, as described above. The cooling liquid is then mixed into the cryoprobe 117 through the inlet 116 to cool the tip 124 in the cryoprobe, but may be solid or hollow depending on the case. The discharged coolant (ie, the coolant that has cooled and expanded the surrounding environment through boiling when the liquid portion of the coolant is decreasing relative to the gas portion) is then lined through the backflow tube 106 of the cryoprobe 117. 119. The exhaust coolant then passes through the two-way valve 120 and is optionally heated by the heater 122 to ensure that the backflow line temperature exceeds the boiling temperature of the coolant so that the exhaust coolant is maintained in the gaseous state. Is done. Optionally and alternatively, the coolant is not heated. In such a case, the gaseous coolant flows through line 124 and flow meter 182 through which the coolant flow rate is measured. As described in more detail below, this flow rate information is one component upon which the pressure regulation for system 100 is based. In some cases, gaseous coolant may be discharged through the safety valve 107 if the flow rate is too high to maintain the desired pressure in the system 100 and / or if the tip 124 cannot be effectively cooled.

  If the gaseous coolant is not discharged, it is sent to the pump 124 and controlled to maintain the desired pressure in the system 100. The pump 134 pumps the gaseous coolant through the line 132 and then through the two-way valve 106 to the gaseous coolant 102. The desired gaseous state of the coolant upon incorporation into the pump 134 is maintained by the heater 122 as described above. In some cases, the gaseous coolant may be pumped to the liquid coolant source 104 through line 131 through two-way valve 103 and line 129 through two-way valve 130. This optional flow path may be advantageous in maintaining a desired pressure differential between the liquid coolant source 104 and the gaseous coolant source 102, as will be described in more detail below.

  The system pressure is measured by pressure gauge 181 for liquid coolant 104 and by pressure gauge pressure gauge 181184 for gas coolant source 102. Preferably, the pressure is higher at the gaseous coolant source 102 than at the liquid pressure source 104.

  Pressure regulator 101 and pump 134 control the total pressure of system 100. More particularly, when the pressure regulator 101 receives information about the pressure of the system 100 from the pressure gauge 181 and flow meter 182, based on this received information, the operation of the pump 134 is controlled by an appropriate electronic circuit (not shown). The pressure in the gaseous coolant source 102 is preferably maintained at a higher level than the pressure in the liquid coolant source 104. In some cases, if the system pressure is excessive, the cooling gas may be discharged via the valve 107. In some cases, the gas coolant may be discharged through the safety valve 191 if the pressure at the liquid coolant source 104 is excessive. Preferably, however, the gaseous coolant is recycled to the gaseous cooling source 102 to maintain the desired pressure within the system 100.

  During the thawing process, the gas coolant flows from the gas coolant source 102 through the line 110, the two-way valve 113, the line 115, and the two-way valve 112 and is heated by the heater 105, and then the heated gas coolant. Enters the cryoprobe 117 through the inlet 108. This gaseous coolant continues to flow to pump 134 through line 119. The pump 134 increases the pressure of the gas coolant and causes the gas coolant to flow backward to the gas coolant source 102. During this operation, all of the gaseous coolant is recycled while the valve 107 remains closed.

  During the initialization process of the system, when flow meter 182 indicates that the coolant is not flowing, pump 134 opens valves 103 and 130 for line 129 and opens valve 107 to allow air to enter. Thus, either air or coolant is initially pumped into the source 104. When the pressure indicator 181 reaches a predetermined (threshold) value, as read by the pressure sensor 184, the valve 103 is closed and the valve 106 is opened and the source until the pressure at the source 102 reaches another predetermined value. The compressed gas is delivered to 102.

  During the refrigeration phase, when the flow meter 182 indicates that the valves 121 and 120 are open and flow is occurring, the pressure measured by the pressure gauge 182 is a desired value or a range of desired values. As long as the pump 134 is maintained, the pump 134 is fully activated to allow the coolant to flow back through the valve 106 to the source 102. If pressure gauge 181 indicates that the pressure is below the desired threshold, pump 134 then pumps coolant into source 104 through valves 103 and 130. During the thawing phase, pump 134 simply recycles coolant through valves 110, 108, and 119 through valves 106, 113, 112, and 120.

  Referring now to FIG. 2, a system 200 adapted for one embodiment of the present invention is illustrated. The system 200 operates in a manner similar to the system 100 of FIG. Accordingly, for ease of explanation, similar components between system 100 and system 200 share corresponding reference numerals and a detailed description thereof is omitted.

  A feature of the system 200 that distinguishes it from the system 100 is that the pump 234 operates stably and recycles the coolant backflow gas. Furthermore, the pump 234 is preferably capable of pumping both liquid coolant and gas coolant. In order to maintain the pressure within the system 200 rather than controlling the operation of the pump 234, the pressure regulator 201 preferably controls the discharge of excess gaseous coolant through the safety valve 291 at the liquid coolant source 204. The pressure gauge 292 is preferably located between the liquid coolant source 204 and the safety valve 291 to determine the pressure at the liquid coolant source 204. Within system 200, if pump 234 can handle liquid as well as gaseous coolant, operation of heater 222 is deferred only when gaseous coolant is discharged through safety valve 207.

  Referring now to FIG. 3, a system 300 that is compatible with one embodiment of the present invention is illustrated. The system 300 operates in a manner similar to the system 100 of FIG. Therefore, for ease of explanation, similar components between system 100 and system 300 share corresponding reference numerals, and detailed descriptions thereof are omitted.

  A feature of the system 300 that distinguishes it from the system 100 is that there is an additional structure for generating a gaseous coolant to fill the gaseous coolant source 302. More specifically, coolant sources 302 and 304 are connected in series from source 304 to source 302 by line 352, two-way valve 353, and line 354. There is also a heater 351 disposed within the source 304.

  In operation, this additional structure generates a gaseous coolant by energizing the heater 351 to heat and boil the liquid coolant in the liquid coolant source 304. The gaseous coolant in liquid coolant source 304 is then preferably transferred directly to gas coolant source 302 through line 352 and two-way valve 353 to bring the pressure at gas coolant source 302 to the desired pressure. Raises rapidly, allowing the system 300 to achieve the desired system pressure more rapidly. The additional structure works well when initializing operation of the system 300 (ie, at the start of cryotherapy).

  Referring now to FIG. 4, a partial system 400 that is compatible with one embodiment of the present invention is illustrated. The system 400 operates in a manner similar to the system 100 of FIG. Accordingly, for ease of explanation, similar components between system 100 and system 400 share corresponding reference numerals and a detailed description thereof is omitted.

  A feature of system 400 that distinguishes it from system 100 is the additional structure for controlling pressure. More specifically, the pressure control structure includes a closed container 451, a line 45 extending from one end of the closed container, and a check valve 461 at the other end of the closed container. The heater 467 is disposed in the closed container 451 and is controlled by the control circuit 462.

  In the system 400, the first source 404 contains a liquid coolant. Within the first source 404 is an additional closed container 451. The container 451 allows coolant to flow through the check valve 461 when the pressure in the first source 404 is greater than the pressure in the container 451. When the electric heater 467 is activated, the pressure in the container 451 is increased and the check valve 461 is closed. As the pressure rises with boiling generated by heating, the gaseous coolant flows in the direction 464 connecting the vessel 451 to a second gaseous coolant source (not shown) at the pressure set by the pressure regulator 463. In the freezing or cooling mode of operation, liquid coolant flows through the filter 414 when the valve 421 is open relative to the cryoprobe (cryosurgical device, not shown) in the direction indicated by arrow 465. When the pressure in the first source 404 is lower than desired, pressurized gas coolant enters through line 429 and there is an additional pressure regulator in the direction indicated by 466 upstream.

  Upon initialization of the system 400, the electric heater 467 is activated to boil the coolant in the vessel 451. When the pressure reaches a predetermined value, the pressure regulator 463 opens and the compressed gaseous coolant is transferred in the direction 464 to a second source (not shown). During other operational phases, system 400 operates in at least the same manner as system 100.

  Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described below. In case of conflict, the patent specification, including definitions, will be subject to regulation. In addition, the materials, methods, and examples described above are illustrative only and not intended to be limiting.

  The various embodiments described above may be selectively combined.

  While embodiments of the invention have been selected and shown and described, it should be understood that the invention is not limited to the embodiments described above. On the other hand, it should be recognized that modifications may be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims (8)

A system for delivering phase-shifting coolant to a surgical device, comprising:
A first reservoir of said coolant in liquid phase;
A liquid supply conduit leading to coolant transfer from the first reservoir to the surgical device;
A second reservoir of said coolant in the gas phase;
A gas delivery conduit leading to coolant transfer from the second reservoir to the surgical device;
A back-flow conduit that is communicated when the coolant discharged from the surgical device flows back to the first and / or second reservoir, while the discharged coolant is in the gas phase;
A pump disposed in the backflow conduit while controlling the backflow of coolant via the coolant backflow path, wherein the pump transfers the coolant in the backflow to the first reservoir and / or the second A coolant back-flow control unit that selectively pumps to the reservoir of
A first pressure sensor for sensing pressure in the first reservoir; a second pressure sensor for sensing pressure in the second reservoir; and information on the first reservoir based on information from the pressure sensor. A pressure controller that regulates pressure, wherein the pressure controller is disposed between the first reservoir and the second reservoir;
A logic portion that selectively energizes the pump and controls the total pressure in the system based on information from pressure sensors and flow meters;
A system comprising:   The system of claim 1, further comprising an exhaust that exhausts cooling gas from the backflow conduit when the pressure in the first reservoir exceeds a specified threshold.   The gas coolant from the cryosurgical device is all recycled from the tip of the cryosurgical device to either one or both of the reservoirs when the drain is closed. system.   The system of claim 1, wherein a pressure regulator regulates the total pressure of the system by regulating the pressure in the first reservoir.   The system of claim 1, further comprising a coolant controller comprising one or more conduits disposed in one or more of the conduits.   The system of claim 19, further comprising a heater disposed in the backflow conduit that selectively heats the coolant in the backflow to maintain a gas phase.   The apparatus cools the tip of the surgical device by delivering a liquid phase coolant to the tip via the liquid supply conduit, and the system cools the second via the gas supply conduit. The system of claim 6, wherein a gas phase coolant is supplied from a reservoir to the tip to keep the tip warm, and the supplied gas phase coolant is kept warm by the heater.   The system of claim 6, wherein the logic portion also controls the heater.

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