A method and system for monitoring the progress of an ice ball produced by a cryoprobe during a surgical procedure measures the complex impedance of the ice ball. An electrical model of the zones in the ice ball is employed to calculate the size of the zones using the complex impedance measurements....http://www.google.de/patents/US6235018?utm_source=gb-gplus-sharePatent US6235018 - Method and apparatus for monitoring cryosurgical operations
