Cryosurgical instrument and related techniques

A cryosurgical instrument comprising:

• a cryoprobe adapted for being positioned in tissue of a patient targeted for cryosurgry and operative to form an ice ball upon activation;
• a sheath disposed over at least a portion of said cryoprobe, wherein said sheath is separable with respect to said cryoprobe;
• at least one measuring device supported by said sheath for measuring a parameter of the tissue of the patient;
• and
• a processor for predicting prior to activation of said cryoprobe formation of said ice ball by said cryoprobe in the tissue of the patient over time in response to an output signal provided by said at least one measuring device.

An instrument for performing cryosurgery comprising:

• at least one cryoprobe adapted for being positioned in tissue of a patient and operative to form an ice ball upon activation;
• a processor for predicting prior to activation of said at least one cryoprobe formation of said ice ball by said at least one cryoprobe in the tissue of the patient over time;
• and
• at least one measuring device coupled to said processor for measuring a parameter of the tissue of the patient and for providing an output signal indicative of said parameter, wherein said processor is responsive to said output signal.

An instrument for performing cryosurgery comprising:

• a plurality of cryoprobes adapted for being positioned in spaced relation in tissue of a patient to form a respective plurality of ice balls upon activation;
• a processor for predicting formation of said plurality of ice balls by said plurality of cryoprobes in the tissue of the patient over time;
• at least one measuring device coupled to said processor for measuring a parameter of the tissue of the patient and for providing an output signal indicative of said parameter, wherein said processor is responsive to said output signal;
• and
• an impedance measurement circuit coupled to selected ones of said plurality of cryoprobes for providing an impedance output signal indicative of the impedance of the tissue of the patient and the size of the plurality of ice balls, wherein said processor is responsive to said impedance output signal for verifying said prediction, and wherein each of said plurality of cryoprobes has an electrically conductive tip portion and an electrically insulative portion adjacent to said tip portion.

A cryosurgical instrument comprising:

• a cryoprobe adapted for being positioned in tissue of a patient targeted for cryosurgery and operative to form an ice ball upon activation;
• a sheath disposed over at least a portion of said cryoprobe, wherein said sheath is separable with respect to said cryoprobe;
• and
• at least one thermistor supported by said sheath for measuring a selected one of temperature, thermal conductivity, and blood perfusion of the tissue of the patient;
• and
• at least one thermocouple supported by said cryoprobe.