The present invention provides a cryogenic device and system for treating biological tissue, which includes at least two media-flow lumens and a media-expansion element for cooling media flowing within the device. A cooling portion of the device is located along a portion of one of the media-flow lumens....http://www.google.com/patents/US6241722?utm_source=gb-gplus-sharePatent US6241722 - Cryogenic device, system and method of using same
