Abstract: Refrigerating apparatus for medical use including a probe comprising two concentric tubes through the inner tube of which, in use of the apparatus, a refrigerant is forced so as to expand into the outer tube as it leaves the inner tube thereby refrigerating the tip of the probe by flash evaporation and expansion, then flowing back along the space between the tubes, in which there are provided two further tubes surrounding the probe except for the refrigerating tip and defining passageways between themselves and the outer tube through which the refrigerant is fed before being introduced into the innermost tube, to provide thermal insulation for the sides of the probe apart from the refrigerating tip.