Abstract: A near critical fluid based cryoablation system comprises a cryoablation catheter for creating a lesion in tissue. A cryogenic fluid is transported under pressure through the catheter. A controller adjusts the pressure from a relatively high (e.g., near critical) pressure to a substantially lower pressure based on a condition during the catheter activation. In one configuration, the pressure is modulated based on the temperature of the catheter. When the temperature of the catheter reaches a target temperature, the pressure is reduced.

Abstract: A method for cryo-induced renal neuromodulation includes applying cryoenergy to neural fibers that contribute to renal function, or to vascular structures that contact, feed or perfuse the neural fibers. In one embodiment, cryoenergy is applied via a distal energy-delivering section of a flexible catheter. The distal section may include a plurality of microtubes for transporting a cryogen to the distal tip. The energy-delivering section contacts and extracts heat from the wall of the renal artery. In one embodiment, the distal energy-delivering section is radially expandable. The renal nerve is cooled to a degree such that nerve function is disrupted.

Abstract: A cryoablation system includes thermally insulated containers for holding liquid refrigerant. The containers are placed in a docking station that charges the containers with a liquid refrigerant at a cryogenic temperature suitable for carrying out a surgical procedure. The charged containers are detachably connectable with an inlet line of a cryoablation probe. When the cryoprobe is activated, the chilled liquid refrigerant is transported from a delivery container, through the cryoprobe, and to a recovery container. The recovery container is preferably identical in design to the delivery container. The refilled recovery container is then placed in the docking station to charge. In another embodiment, a cartridge includes a delivery container and recovery container combined as a single unit. Methods are also described.

Abstract: A cryoablation system includes thermally insulated containers for holding liquid refrigerant. The containers are placed in a docking station that charges the containers with a liquid refrigerant at a cryogenic temperature suitable for carrying out a surgical procedure. The charged containers are detachably connectable with an inlet line of a cryoablation probe. When the cryoprobe is activated, the chilled liquid refrigerant is transported from a delivery container, through the cryoprobe, and to a recovery container. The recovery container is preferably identical in design to the delivery container. The refilled recovery container is then placed in the docking station to charge. In another embodiment, a cartridge includes a delivery container and recovery container combined as a single unit. Methods are also described.

Abstract: A system and method for use with at least one cryoprobe for the treatment of biological tissue controls the energy applied to the tissue. The invention receives live procedure data such as temperature information from locations along the pathway of the cryogenic liquids, and calculates a procedure signature or profile based on the procedure data. In one embodiment, volumetric isotherms are calculated. The procedure signature is compared to a planning signature based on previously acquired image data and estimates of the thermal gradients from models. The system and method are further configured to automatically regulate the application of power based on analysis of the planning data to the procedure data.

Abstract: Cryoablation balloon catheters and methods are described herein. The cryoablation balloon catheter comprises a distal end section and an inflatable balloon member disposed along the distal end section for contacting a target tissue. The balloon member may be inflated with a thermally conductive liquid. One or more cooling microtubes are positioned within the balloon and a single phase liquid coolant is transported from a liquid source, through the microtubes to the distal section, and returned to a reservoir. Cryogenic energy is transferred from the microtubes, through the conductive liquid filling the balloon, through the wall of the balloon, and to the tissue. In a cryoablation balloon catheter, a plurality of flexible microtubes are adhered to a surface of the expandable balloon. Cryoenergy from the microtubes is directly transferred to the tissue.

Abstract: A cryoablation apparatus includes a distal energy delivery section to facilitate energy transfer to the tissue, resulting in faster achievement of tissue target temperatures. The energy delivery section includes a first heat exchange region and a second heat exchange region having a different heat exchange efficiency than the first heat exchange region. The first heat exchange region may comprise an increased surface area along a radial portion or length of the cryoprobe in contact with surrounding tissue. The heat exchange region may include ridges, texture, threads, and microtubes which serve to increase the thermal-contacting surface area and provide enhanced cryoenergy to the tissue.

Abstract: A system and method for use with at least one cryoprobe for the treatment of biological tissue controls the energy applied to the tissue. The invention receives live procedure data such as temperature information from locations along the pathway of the cryogenic liquids, and calculates a procedure signature or profile based on the procedure data. In one embodiment, volumetric isotherms are calculated. The procedure signature is compared to a planning signature based on previously acquired image data and estimates of the thermal gradients from models. The system and method are further configured to automatically regulate the application of power based on analysis of the planning data to the procedure data.

Abstract: A method for cryo-induced renal neuromodulation includes applying cryoenergy to neural fibers that contribute to renal function, or to vascular structures that contact, feed or perfuse the neural fibers. In one embodiment, cryoenergy is applied via a distal energy-delivering section of a flexible catheter. The distal section may include a plurality of microtubes for transporting a cryogen to the distal tip. The energy-delivering section contacts and extracts heat from the wall of the renal artery. In one embodiment, the distal energy-delivering section is radially expandable. The renal nerve is cooled to a degree such that nerve function is disrupted.

Abstract: A cryoablation system includes thermally insulated containers for holding liquid refrigerant. The containers are placed in a docking station that charges the containers with a liquid refrigerant at a cryogenic temperature suitable for carrying out a surgical procedure. The charged containers are detachably connectable with an inlet line of a cryoablation probe. When the cryoprobe is activated, the chilled liquid refrigerant is transported from a delivery container, through the cryoprobe, and to a recovery container. The recovery container is preferably identical in design to the delivery container. The refilled recovery container is then placed in the docking station to charge. In another embodiment, a cartridge includes a delivery container and recovery container combined as a single unit. Methods are also described.

Abstract: Single phase liquid refrigerant cryoablation systems and methods are described herein. The cryoablation systems drive liquid cryogen or refrigerant along a closed fluid pathway without evaporation of the liquid cryogen. A cryoprobe includes a distal energy delivery section to transfer energy to the tissue. A plurality of cooling microtubes positioned in a distal section of the cryoprobe transfer cryogenic energy to the tissue. The plurality of microtubes in the distal section are made of materials which exhibit flexibility at cryogenic temperature ranges, enabling the distal section of the cryoprobe to bend and conform to variously shaped target tissues.

Abstract: A system and method for use with at least one cryoprobe for the treatment of biological tissue controls the energy applied to the tissue. The invention receives live procedure data such as temperature information from locations along the pathway of the cryogenic liquids, and calculates a procedure signature or profile based on the procedure data. In one embodiment, volumetric isotherms are calculated. The procedure signature is compared to a planning signature based on previously acquired image data and estimates of the thermal gradients from models. The system and method are further configured to automatically regulate the application of power based on analysis of the planning data to the procedure data.

Abstract: A gas-based cryotherapy probe is provided with a shaft having a closed distal end adapted for insertion into a body. A supply conduit is disposed longitudinally within the shaft for flowing gas towards the distal end, and a return conduit is disposed longitudinally within the shaft for flowing gas from the distal end. The gas is maintained at a lower pressure within the return conduit than in the supply conduit. A heat exchanger is disposed within the shaft in thermal communication with the supply conduit and return conduit to exchange heat from gas in the supply conduit to gas in the return conduit. A vacuum jacket is adapted to provide thermal isolation of the heat exchanger from the shaft.

Abstract: A cryotherapy system is provided with multiple cryoprobes, each of which has a shaft with a closed distal end adapted for insertion into a body and conduits for flowing a cryogenic fluid through the shaft to reduce a temperature of the distal end. A source is provided for the cryogenic fluid, and flow-control metering valves are provided in fluid communication with the conduits and source of the cryogenic fluid. A compressor is provided in fluid communication with the conduits of the cryoprobes to define a self-contained fluid system. The flow-control metering valves and the compressor are controlled by a computer processor to provide the desired flows of the cryogenic fluid through the conduits of the self-contained fluid system.

Abstract: Methods and systems are provided for cooling an object with a cryogen having a critical point defined by a critical-point pressure and a critical-point temperature. A pressure of the cryogen is raised above a pressure value determined to provide the cryogen at a reduced molar volume that prevents vapor lock. Thereafter, the cryogen is placed in thermal communication with the object to increase a temperature of the cryogen along a thermodynamic path that maintains the pressure greater than the critical-point pressure for a duration that the cryogen and object are in thermal communication.