Cryosurgical probe

A cryosurgical probe comprising a probe head for applying a bodily tissue to be frozen and provided with a cavity, flexible catheter means connected to said probe head for guiding said probe head along an artery of the body, first and second passageways in said catheter means leading to said cavity of said probe head, a restriction in said first passageway such that a refrigerant at high pressure passed therealong suffers cooling after passage through the restriction to cause a reduction in temperature in said probe head, said second passageway being provided to exhaust the cooled refrigerant from said cavity, a bracing support means positioned axially along the length of said catheter means for supporting said first passageway, said first passageway having several coils adjacent said probe end of said cathether means, said coils forming a heat exchanger between warmer primary refrigerant in said first passageway and cooler exhaust refrigerant in said second passageway, and said bracing support means including a thermocouple for monitoring the temperature of said tip of said probe head.