Abstract: An elongated catheter device with a distal balloon assembly is adapted for endovascular insertion. Coolant injected through the device may, in different embodiments, directly cool tissue contacting the balloon, or may cool a separate internal chamber. In the first case, the coolant also inflates the balloon, and spent coolant is returned to the handle via a return passage extending through the body of the catheter. Plural balloons may be provided, wherein a secondary outer balloon surrounds a primary inner balloon, the primary balloon being filled with coolant and acting as the cooling chamber, the secondary balloon being coupled to a vacuum return lumen to serve as a robust leak containment device and thermal insulator around the cooling chamber. Various configurations, such as surface modification of the balloon interface, or placement of particles, coatings, or expandable meshes or coils in the balloon interface, may be employed to achieve this function.

Abstract: A surgical device includes a device body defining a sealed fluid path having a first end and a second end, a refrigerant supply in communication with the first end of the sealed fluid path, and a vacuum source in communication with the second end of the sealed fluid path. Leak detection apparatus can be provided in communication with the sealed fluid path.

Abstract: The invention relates to a cryoinstrument which is provided for carrying out cryosurgical interventions in the area of human and veterinary medicine, especially for treating tumors, and in the area of phytopathology and which is connected to a connecting device of a cryogenic appliance or system. The inventive cryoinstrument is comprised of a housing (1) in which a line is located that is provided for the direct flow (2) and for the return flow (3) of a cryogenic medium, e.g. liquid nitrogen. The housing has at least one closed end piece (4) which forms a working surface (5) with an exterior side (6) for cooling a tissue, and has a temperature sensor (7). In order to be able to constantly maintain the minimal temperature, in particular, between −40° C. and −196° C.

Abstract: Methods and apparatus for cryo-therapy are disclosed herein. This includes a hollow guidewire disposed within a catheter having helical loops contacting tissue. A coolant delivery tube disposed within can have a coolant delivered from a proximal end into the guidewire lumen. The coolant flows back proximally through the guidewire while cooling the guidewire surface and cooling or cryogenically ablating the contacting tissue. To minimize guidewire exposure to surrounding fluids or tissue, insulative barriers can be attached to the guidewire. A coolant delivery tube and return lumen can be integrated from a single extrusion in various configurations. Expandable balloons can also be used to expand the loops of the guidewire to contact the tissue. Also, helical loops with a coolant delivery tube or stem disposed longitudinally within the loops can be used and the loops can also have a variable collapsible cooling region.

Abstract: The present invention relates to a cryoablation catheter, comprising an outer tubular body with a closed distal end to form a fluid cooling chamber and an inner tubular member having a proximal end adapted to receive fluid suitable for cryoablation and a distal end coupled to a fluid expansion nozzle wherein the inner tubular member is movable in an axial direction to thereby change the position of the nozzle within the fluid cooling chamber.

Abstract: Cryosurgery is performed with cryosurgical probe tips either contacting the tissue or by tips which deliver refrigerant onto the tissue. A dual action probe tip can be used to perform either operation separately or may be used for application of both methods. Various method steps define the procedures for use of the probe tips.

Abstract: A cryoablation catheter having an expandable cooling chamber in which the cooling fluid, preferably a gas, serves to expand the expandable cooling chamber while simultaneously cooling the chamber.

Abstract: A method of promoting blood vessel growth includes the steps of providing a cryocatheter having a thermally transmission region; placing the cryocatheter proximate an area of tissue to be treated; cooling the thermally transmissive region of the cryocatheter proximate the area of tissue to a temperature sufficient to injure the area of tissue; allowing the area of tissue to warm; and removing the cryocatheter from the area of tissue. Prior, during or after the cooling step, the area of tissue can be mechanically traumatized, and drugs can be injected into the tissue.

Abstract: The present invention provides a medical device to cold treat desired regions. An injection tube with an open distal end is disposed inside of a catheter tube, defining a return lumen therein. A supply of cryogenic fluid, regulated by a controller mechanism coupled to the device, flows through the injection tube and into the distal tip portion of the catheter tube, whereupon the fluid is returned from the catheter through the return lumen. The expansion and evaporation of cryogenic fluid inside the device serves to cool the surrounding areas external to and proximate the distal end of the device. An additional restriction tube is provided in the length of the catheter tube to regulate the pressure of the flow of cryogen therethrough so as to create higher operating pressures in the distal end of the device and thereby enhance the cooling power and temperature stability of the device at a lower range of fluid flow rates without reaching the triple point of the cryogenic fluid.

Abstract: A method and apparatus for inflating a balloon at a distal portion of an elongated delivery catheter to contact surrounding biological tissue, and expanding a refrigerant adjacent the balloon to cool the biological tissue to render it non-viable. The inflation of the balloon can be accomplished with the expanded refrigerant or with a separate pressurized fluid. The balloon can act as a heat transfer element, or there can be a separate heat transfer element on the catheter adjacent the balloon. The apparatus can be used to perform a dilation procedure, such as angioplasty, in conjunction with cooling of the surrounding tissue.

Abstract: The invention provides improved devices, methods, and systems for shrinking of collagenous tissues, particularly for treating urinary incontinence in a noninvasive manner by directing energy to a patient's own support tissues. This energy gently heats fascia and other collagenous support tissues, causing them to contract. The energy will preferably be applied between a pair of large plate electrodes having cooled flat electrode surfaces separated by an insulating rib or film. Such cooled plate electrodes are capable of directing electrical energy through an intermediate tissue and into fascia while the cooled electrode surface prevents injury to the intermediate tissue.

Abstract: A catheter and a method of using the catheter are disclosed that serve to create an efficient and rapid controlled manner of regulating a patient's body temperature. The catheter is a heat exchange catheter insertable into a blood vessel of a patient, circulating a heat exchange fluid therein, and including a spiral-shaped inflatable balloon that mixes laminar layers of the heat exchange fluid flowing inside the balloon.

Abstract: The invention relates to a catheter and method for controlling tissue remodeling or proliferation. The catheter includes an outer balloon located on a distal end of the catheter, a first lumen in fluid communication with the outer balloon and fluidly connected to a source of liquid for expanding the outer balloon with liquid to contact the tissue site, and a second lumen fluidly connected to a source of coolant fluid at a proximal end for transporting the coolant fluid to a distal end of the second lumen to cool the liquid in the outer balloon and thereby the tissue site to a cryo-therapeutic temperature. The second lumen includes an orifice configured and dimensioned to allow the coolant fluid to expand as it passes therethrough to reduce coolant fluid temperature. In another embodiment, the outer balloon is coated or expanded with a media.

Abstract: The present invention features various methods and systems for performing radiation treatment of skin in connection with dynamic cooling of tissue, while minimizing or preventing occurrence of light flash during the treatment.

Abstract: Methods and apparatus for dermatology treatment are provided which involve the use of continuous wave (CW) radiation, preheating of the treatment volume, precooling, cooling during treatment and post-treatment cooling of the epidermis above the treatment volume, various beam focusing techniques to reduce scattering and/or other techniques for reducing the cost and/or increasing the efficacy of optical radiation for use in hair removal and other dermatological treatments. A number of embodiments are included for achieving the various objectives indicated above.

Abstract: A cryocatheter for treatment of tissue has a tip adapted to provide a signal indicative of the quality and/or orientation of the tip contact with surrounding tissue. In one embodiment, a signal conductor extends through the catheter to the tip and connects to a thermally and electrically conductive shell or cap that applies an RF current to the region of tissue contacted by the tip. The tissue impedance path between the signal lead and a surface electrode mounted on the patient's skin is monitored to develop a quantitative measure of tissue contact at the distal tip, which is preferably displayed on the screen of a catheter monitoring console. In yet a further embodiment, the catheter is provided with a split tip having temperature monitoring sensors, such as thermistors, mounted on opposed halves of the tip so as to sense temperature on two sides of the catheter axis.

Abstract: An intralesional method for treating a hypertrophic scar or keloid using a cryoprobe. The method comprises: (a) inserting the cryoprobe into the hypertrophic scar or keloid so that the cryoprobe is positioned within the hypertrophic scar or keloid; and (b) introducing a cryogen into the cryoprobe thereby freezing the hypertrophic scar or keloid. The cryoprobe has a sealed distal end comprising a cutting tip. Also disclosed is a cryoprobe comprising an elongated, uninsulated housing having a sealed distal end and a proximal end. The housing comprises therein a cryogen inlet tube. The cryoprobe further comprises a cutting tip at the distal end of the housing and a cryogen vent adjacent to the proximal end and in fluid communication with the interior of the housing.

Abstract: A surgical device includes a device body defining a sealed fluid path having a first end and a second end, a refrigerant supply in communication with the first end of the sealed fluid path, and a vacuum source in communication with the second end of the sealed fluid path. Leak detection apparatus can be provided in communication with the sealed fluid path.

Abstract: The present invention relates to a cryoablation catheter, comprising an outer tubular body with a closed distal end to form a fluid cooling chamber and an inner tubular member having a proximal end adapted to receive fluid suitable for cryoablation and a distal end coupled to a fluid expansion nozzle wherein the inner tubular member is movable in an axial direction to thereby change the position of the nozzle within the fluid cooling chamber.

Abstract: A cryoablation catheter having a high efficiency gas expansion chamber comprised of a generally cylindrical or hemispherical cooling chamber having a wall thickness equal to approximately one half the wall thickness of the walls of the catheter in order to provide a cooling chamber increased with large gas expansion volume and having thin walls for rapid cooling of the outside surface of the cooling chamber.

Abstract: A sheath for use on a closed loop Joule-Thomson cryosurgical probe, and the combination of the and the closed loop probe. The sheath is slipped over the probe, thereby separating the probe from the environment. The sheath has a grip which fits over the handle of the cryosurgical probe, and an extendible shroud which can be longitudinally extended to cover tubing and which are attached to the handle. The sheath has a hollow multi-lumen catheter shaped and sized to fit snugly over the cannula of the cryosurgical probe. The catheter is not thermally conductive, preventing transfer of heat from the ambient to the gas mixture, and preventing the freezing of tissues at undesired locations along the catheter. A thermally conductive cap or tip is attached to the distal end of the hollow catheter. The thermally conductive cap or tip fits snugly over the cold tip on the probe, and it efficiently transfers heat from the target tissue to the cold tip, which in turn transfers heat to the expanded gas mixture.

Abstract: A cryocatheter for treatment of tissue has a tip adapted to provide a signal indicative of the quality and/or orientation of the tip contact with surrounding tissue. In one embodiment, a signal conductor extends through the catheter to the tip and connects to a thermally and electrically conductive shell or cap that applies an RF current to the region of tissue contacted by the tip. The tissue impedance path between the signal lead and a surface electrode mounted on the patient's skin is monitored to develop a quantitative measure of tissue contact at the distal tip, which is preferably displayed on the screen of a catheter monitoring console. In yet a further embodiment, the catheter is provided with a split tip having temperature monitoring sensors, such as thermistors, mounted on opposed halves of the tip so as to sense temperature on two sides of the catheter axis.

Abstract: The invention relates to a cryogenic system which is provided for performing cryosurgical interventions in the area of human and veterinary medicine, especially for treating tumors. The inventive system is comprised of a cryostat (1) and of a connecting device (8) which is located between coaxial cryogenic lines for the direct flow (9) and return flow (10) of the cryogenic medium and which is provided for connecting a cryoinstrument (17) to a cryo-attachment (13). The electromagnetic valve (11) is located in the immediate proximity of the connecting device (8). A regulating device (18) is provided for controlling the electromagnetic valves (2, 3, 4 and 7) as well as the heating element (12), and regulates the excess pressure of the cryogenic medium in the cryostat (1) to an accuracy of ±0.1×105 Pa. The bottle neck (23) of the cryostat (1) is made of a material exhibiting a low level of thermal conductivity.

Abstract: The present invention pertains generally to the field of cryo balloon therapy and the use of cryo balloon therapy catheters to generate cold-induced lesions. The present invention includes a cryo balloon therapy apparatus, comprising a catheter having a proximal and a distal end, a cooling member disposed at the distal end of the catheter, a pull cord coupled to the cooling member, and a sheath that couples the pull cord and the catheter. A method for causing cold-induced necrosis is also disclosed.

Abstract: The present invention provides a medical device to cold treat desired regions. An injection tube with an open distal end, and at least one aperture proximate thereto is disposed inside of a cooling tube, defining a cooling lumen therebetween. A third outer tube member is disposed around the second cooling member, defining a return lumen therebetween. A supply of fluid, regulated by a controller mechanism coupled to the device, flows through the injection lumen, the apertures and the cooling lumen to insulate and cool the fluid supplied into the injection lumen. The supplied fluid flows through the injection lumen and its distal end into the return lumen to cool the surrounding areas external to and proximate the distal end of the device.

Abstract: A heat exchange catheter having an expandable insulating region thereon. The catheter has a heat exchange region and the insulating region disposed proximally thereto. The insulating region assumes a first size about a catheter shaft to facilitate insertion of the catheter into the body. Once the insulating region is inserted into the body, the insulating region is expanded a second size. The insulating region may be a balloon around the catheter shaft that is inflated to the second size to create a gap between the wall of the balloon and the catheter shaft. Heat flows through the catheter shaft to and from the heat exchange region, and thus heat loss or gain to and from the surrounding body is minimized in the insulating region. The exchange region may include a fluid circulation path comprised of lumens through the catheter shaft.

Abstract: Improved systems, devices, and methods for delivering cryogenic cooling fluid to cryosurgical probes such as cryosurgical endovascular balloon catheters take advantage of the transients during the initiation and termination of cryogenic fluid flow to moderate the treatment temperatures of tissues engaged by the probe. A flow limiting element along a cryogenic fluid path intermittently interrupts the flow of cooling fluid, often cycling both the fluid flow and treatment temperature. This can maintain the tissue treatment temperature within a predetermined range which is above the treatment temperature provided by a steady flow of cryogenic fluid. In another aspect, room temperature single-use cooling fluid cartridges are filled with a sufficient quantity of cryosurgical fluid to effect a desired endovascular cryosurgical treatment.

Abstract: A cryogenic catheter includes an outer flexible member having at least one cryogenic fluid path through the flexible member. The at least one fluid path is defined by a plurality of flexible members disposed within the outer flexible member.

Abstract: The present invention provides an enhanced method and device to inhibit or reduce the rate of restenosis following angioplasty or stent placement. The invention involves placing a balloon tipped catheter in the area treated or opened through balloon angioplasty immediately following angioplasty. The balloon, which can have a dual balloon structure, may be delivered through a guiding catheter and over a guidewire already in place from a balloon angioplasty. A fluid such as a perfluorocarbon may be flowed into the balloon to freeze the tissue adjacent the balloon, this cooling being associated with reduction of restenosis. The catheter may also be used to reduce atrial fibrillation by inserting and inflating the balloon such that an exterior surface of the balloon is in contact with at least a partial circumference of the portion of the pulmonary vein adjacent the left atrium.

Abstract: Surgical methods and instruments are disclosed for performing port-access or closed-chest coronary artery bypass (CABG) surgery in multivessel coronary artery disease. In contrast to standard open-chest CABG surgery, which requires a median sternotomy or other gross thoracotomy to expose the patient's heart, port-access CABG surgery is performed through small incisions or access ports made through the intercostal spaces between the patient's ribs, resulting in greatly reduced pain and morbidity to the patient. In situ arterial bypass grafts, such as the internal mammary arteries and/or the right gastroepiploic artery, are prepared for grafting by thoracoscopic or laparoscopic takedown techniques. Free grafts, such as a saphenous vein graft or a free arterial graft, can be used to augment the in situ arterial grafts. The graft vessels are anastomosed to the coronary arteries under direct visualization through a cardioscopic microscope inserted through an intercostal access port.

Abstract: A cryogenic catheter includes an outer flexible member having at least one cryogenic fluid path through the flexible member. The at least one fluid path is defined by a plurality of flexible members disposed within the outer flexible member.

Abstract: Surgical methods and instruments are disclosed for performing port-access or closed-chest coronary artery bypass (CABG) surgery in multivessel coronary artery disease. In contrast to standard open-chest CABG surgery, which requires a median sternotomy or other gross thoracotomy to expose the patient's heart, port-access CABG surgery is performed through small incisions or access ports made through the intercostal spaces between the patient's ribs, resulting in greatly reduced pain and morbidity to the patient. In situ arterial bypass grafts, such as the internal mammary arteries and/or the right gastroepiploic artery, are prepared for grafting by thoracoscopic or laparoscopic takedown techniques. Free grafts, such as a saphenous vein graft or a free arterial graft, can be used to augment the in situ arterial grafts. The graft vessels are anastomosed to the coronary arteries under direct visualization through a cardioscopic microscope inserted through an intercostal access port.

Abstract: A method for applying energy to biological tissue. An electromagnetic energy source is directed to apply the energy to a region of the tissue, so as to ablate a portion of the tissue in the region. Preferably, cooling of tissue in the region is initiated subsequent to the ablation.

Abstract: A method of stabilizing a tissue mass, using a system (8) that includes temperature sensors (10), a scanner (80), and a cryoprobe (220). The sensors provide temperature information with respect to a tissue portion adjacent thereto. The sensors include an identification (ID) code and an ID decoder. The ID decoder compares the sensor ID code to an ID code contained in an interrogation signal provided by the scanner. If the codes match, the sensor transmits the temperature information to the scanner, which processes and displays the temperature information in a humanly recognizable form. The method includes the step of inserting a cryoprobe into a tissue volume to be stabilized so that a portion of the cryoprobe projects therefrom. Then, the tissue volume is frozen while monitoring the size or temperature of the tissue volume. Freezing is terminated when the tissue volume is frozen (or reaches a first temperature level), and then removed while grasping the cryoprobe so as to stabilize the tissue volume.

Abstract: A cryogenic catheter includes an outer flexible member having at least one cryogenic fluid path through the flexible member. The at least one fluid path is defined by a plurality of flexible members disposed within the outer flexible member.

Abstract: In methods and apparatus for cooling surfaces, a pressurized liquid refrigerant is dispensed through a shaped member composed of an open celled foam. The method is particularly useful for localized freezing of a wart or other growth prior to its removal from skin of a human being or another animal.

Abstract: A hair removal device (22) includes a cooling surface (34) which is used to contact the skin (6) prior to exposure to hair tissue-damaging laser light (74) passing from a radiation source (36) through a recessed window (46). The window is laterally offset from the cooling surface and is spaced apart from the cooling surface in a direction away from the patient's skin to create a gap between the window and the skin. The window preferably includes both an inner window (46) and an outer, user-replaceable window (48). The laser-pulse duration is preferably selected according to the general diameter of the hair.

Abstract: A method of reducing tissue volume for treatment of airway obstruction, obstructive sleep apnea, snoring, prostate tumor, and other pathologies comprising: applying a cryoprobe with a diameter preferably less than about 2 mm and with a sharp tip to first freeze the affected interstitial tissue of the soft palate, base of the tongue, tonsils or adenoids, singularly or in combination, or to the prostate, or other tissue, and then applying the same cryoprobe to heat the treated tissue.

Abstract: The present invention is directed towards a combined electrosurgical-cryosurgical instrument for tissue ablation. The instrument comprises a shaft having a proximal end and a distal end, the distal end being electrically and thermally conductive; a radiofrequency insulation sheath surrounding the outer surface of the shaft; a cryo-insulation sheath surrounding a surface of the shaft; a radiofrequency power supply source; a cryogen supply tube within the shaft; and a cryogen supply source connected to the cryogen supply tube. The power source provides electrical energy to the distal end of the shaft, and the cryogen supply tube provides a cryogen to the distal end of the shaft.

Abstract: An enhanced method and device are provided to inhibit or reduce restenosis following angioplasty or stent placement. A porous balloon-tipped catheter is disposed in the area treated or opened through balloon angioplasty immediately following angioplasty. The balloon, which can have a dual balloon structure, may be delivered through a guiding catheter and over a guidewire already in place. A fluid such as a perfluorocarbon flows into the balloon to freeze the tissue adjacent the balloon, this cooling being associated with reduction of restenosis. A similar catheter may be used to reduce atrial fibrillation by inserting and inflating the porous balloon such that an exterior surface of the balloon, as well as a portion of the cold working fluid, from the microporosity contacts at least a partial circumference of the portion of the pulmonary vein adjacent the left atrium.

Abstract: The present invention is directed towards a surgical system and method of use for treating and removing unwanted tissue, preferably from an organ or other internal part of a patient. The system includes a cryosurgical component for first freezing the unwanted living tissue by forming an ice mass which completely encompasses the unwanted living tissue and means for treating the cryogenically-treated tissue and then removing the tissue while it remains in a frozen state. In one embodiment, an ultrasonic device is used to ultrasonically vibrate the cryogenically-treated tissue to break apart the frozen tissue and the frozen broken-up pieces of tissue are removed using a technique, such as an aspiration process.

Abstract: The invention provides a method and apparatus for producing reversible focal hypothermia of the nervous system to control chronic pain. Nerve conduction is blocked by mild cooling (0 to 25° C.), or hypothermia. At these temperatures, nerve tissue is not destroyed and recovers completely when cooling is terminated, such that the treatment is reversible. By blocking conduction in pain nerves, pain sensation is eliminated in a manner analogous to drugs such as lidocaine that also block nerve conduction to provide anesthesia. The invention can be applied to a variety of conditions such as urge incontinence, muscle spasticity, and epilepsy. Many of these disorders are mediated by nerve and nervous tissue that could be interrupted by cooling. In addition, neurologic dysfunction found in multiple sclerosis may improve by cooling of the nerves. The method and apparatus may be used to cool areas of the nervous system affected by multiple sclerosis to allow more normal functions.

Abstract: A cryoplasty catheter and method for preventing or slowing reclosure of a lesion following angioplasty. The cryoplasty catheter includes a shaft having proximal and distal ends and a dilatation balloon disposed at the distal end. An intake lumen and exhaust lumen are defined by the shaft to deliver coolant to the balloon and to exhaust or drain coolant from the balloon. The method in accordance with the present invention includes cooling a lesion to aid in remodeling the lesion through dilatation and/or freezing a portion of the lesion adjacent the dilatation balloon to kill cells within the lesion to prevent or retard restenosis.

Abstract: Post-angioplasty hyperplasia in blood vessels is treated using a cryosurgical balloon catheter. The balloon catheter is positioned at a target region within the blood vessel, and the balloon inflated by expanding a cryogenic fluid, such as liquid nitrogen, across an expansion orifice into a balloon. The balloon will be constructed so that cooling is achieved primarily in the central regions of the balloon, with the proximal and distal regions being less cold and acting to insulate adjacent regions of the blood vessel from excessive cooling.

Abstract: A probe contacts targeted tissue, sometimes while positioned adjacent to nontargeted live tissues. In preferred forms, the probe includes a support that only minimally conducts heat from nontargeted tissues. A very conductive targeted-tissue-contacting element, at an end of the support, is immersed in a liquid cryogen (preferably nitrogen) and then removed for contacting with (e. g., insertion into) the targeted tissue. An ultrathin highly thermoconductive polymeric tubing holds both a very conductive, cold material, forming the targeted-tissue-contacting element, and fine insulating material (e. g. highly insulating elastomer) forming part of the support. The targeted-tissue-contacting element is fashioned to fit the targeted tissue in at least one dimension, and the support to fit nontargeted live tissues (if any) adjacent to which the probe is positioned while contacting the targeted tissue.

Abstract: Post-angioplasty hyperplasia in blood vessels is treated using a cryosurgical balloon catheter. The balloon catheter is positioned at a target region within the blood vessel, and the balloon inflated by expanding a cryogenic fluid, such as liquid nitrogen, across an expansion orifice into a balloon. The balloon will be constructed so that cooling is achieved primarily in the central regions of the balloon, with the proximal and distal regions being less cold and acting to insulate adjacent regions of the blood vessel from excessive cooling.

Abstract: The cryoprobe assembly includes a cryoprobe and an outer sheath assembly detachably connected thereto. The cryoprobe includes: a Joule-Thomson nozzle; a high pressure gas supply line for supplying gas to the Joule-Thomson nozzle; a heat exchanger interposed between the high pressure gas supply line and the Joule-Thomson nozzle; a cryoprobe sheath containing the heat exchanger and Joule-Thomson nozzle, the cryoprobe sheath having an outer surface; and, a handle attached to the first sheath, the handle having a gripping portion directly graspable by an operator and a connecting portion. The outer sheath assembly includes an adapter covering substantially none of the gripping portion of the cryoprobe handle. The adapter is for attachment to the connecting portion. An outer sheath is connected to the adapter and surrounds the outer surface of the cryoprobe sheath wherein the outer sheath provides enhanced protection against any gas leaks.

Abstract: Improved systems, devices, and methods for delivering cryogenic cooling fluid to cryosurgical probes such as cryosurgical endovascular balloon catheters take advantage of the transients during the initiation and termination of cryogenic fluid flow to moderate the treatment temperatures of tissues engaged by the probe. A flow limiting element along a cryogenic fluid path intermittently interrupts the flow of cooling fluid, often cycling both the fluid flow and treatment temperature. This can maintain the tissue treatment temperature within a predetermined range which is above the treatment temperature provided by a steady flow of cryogenic fluid. In another aspect, room temperature single-use cooling fluid cartridges are filled with a sufficient quantity of cryosurgical fluid to effect a desired endovascular cryosurgical treatment.

Abstract: A cryogenic catheter includes an outer flexible member having at least one cryogenic fluid path through the flexible member. The at least one fluid path is defined by a plurality of flexible members disposed within the outer flexible member.

Abstract: A cooling apparatus having an inflatable balloon near a distal end of a multi-lumen catheter, with a plurality of blood flow passageways formed through the interior of the balloon from a proximal face of the inflated balloon to a distal face of the inflated balloon. Chilled saline solution is introduced through a supply lumen of the catheter to inflate the balloon in a feeding artery of the selected organ; this allows blood to flow through the blood flow passageways of the balloon, from one exterior face of the balloon to another exterior face. The saline solution continues to circulate around the blood flow passageways inside the balloon, to cool the blood, eventually exiting the balloon through a return lumen of the catheter.