Modular pulsed pressure device for the transport of liquid cryogen to a cryoprobe

Abstract

A cryogenic medical device for delivery of subcooled liquid cryogen to various configurations of cryoprobes is designed for the treatment of damaged, diseased, cancerous or other unwanted tissues. The device is a closed or semi-closed system in which the liquid cryogen is contained in both the supply and return stages. The device is capable of generating cryogen to a supercritical state and may be utilized in any rapid cooling systems. As designed, the device comprises a number of parts including a vacuum insulated outer dewar, submersible cryogen pump, baffled linear heat exchanger, multiple pressurization cartridges, a return chamber, and a series of valves to control the flow of the liquid cryogen. The cryogenic medical device promotes the subcooling to any external cryogenic instrument.

1 . A method of delivering cryogen to a cryoprobe, said method comprising the steps of:
 providing a device containing cryogen, said device having one or more ports;   providing a pump submersed within the cryogen;   providing at least one pressurized apparatus within said device, said pressurized apparatus having an immersion heater contained therein, at least one inlet port, and at least one outlet port;   providing an instrument outside said device for use in cooling processes, said instrument connected to one or more supply lines which interconnect with said device;   activating said pressurized apparatus to form pressurized cryogen; and   directing said pressurized cryogen to said instrument through said one or more supply lines.   
     
     
         2 . The method of  claim 1 , further comprising a step of delivering said pressurized cryogen to a heat exchanger prior to said step of directing said pressurized cryogen to said instrument. 
     
     
         3 . The method of  claim 1 , further comprising a step of sealing said device to form a closed system. 
     
     
         4 . The method of  claim 1 , wherein said instrument is a cryoprobe utilized in cryotherapeutic procedures. 
     
     
         5 . The method of  claim 1 , wherein said step of providing said pressurized apparatus comprises a step of arranging two or more of said pressurized apparatuses in series. 
     
     
         6 . The method of  claim 5 , wherein said step of activating said pressurized apparatus includes a step of pressurizing each of said pressurized apparatuses and releasing said pressurized cryogen in a continual series of pulsations. 
     
     
         7 . The method of  claim 1 , further comprising a step of recirculating the cryogen through said device by way of one or more return lines. 
     
     
         8 . The method of  claim 1 , further comprising a step of generating supercritical cryogen within said at least one pressurized apparatus. 
     
     
         9 . The method of  claim 1 , further comprising a step of generating pressurized cryogen within said at least one pressurized apparatus.