US Patent 7361187 Threaded cryostat for cryosurgical probe system

The threaded cryostat for a cryosurgical probe system includes an outer tube and a hollow elongated threaded element positioned within the outer tube. The threaded element has integral, external threads that extend from on an outer surface thereof. During operation a working fluid is transported in a first direction between a fluid supply line and a distal end of a cryosurgical probe within a first space defined within the threaded element. Working fluid is transported in a second direction between the distal end of the cryosurgical probe and the fluid supply line within a second space defined between the outer tube and the threaded element.