A cryogenic probe design is provided containing, for example, an inner coil injection tube with a continuous flow of circulating liquid and an outer jacket enclosing the inner coil injection tube. A transducer may monitor parameters in the region between the inner coil injection tube and the outer jacket. An outer jacket serves to prevent gas leakage. One or more embodiments of a probe design provide continuous flow for example via a continuous and controlled path from inlet to outlet and an expanded thermally transmissive region. Expanding a thermally transmissive region of the cooling zone may be provided, for example, in one or more embodiments of injection tube designs.