Abstract: An apparatus for controlling the temperature of a part of a human or animal body 2 during a cryosurgical procedure is disclosed. The apparatus comprises a radiative energy transmitter 26 for radiating energy to a zone of the body 2 to be protected from excessive cooling. There is also provided a means 12 for controlling the energy radiated by said radiative energy transmitter 26. Preferably the radiative energy transmitter comprises an infra-red laser diode coupled to a diffuser 34 by an optical fibre 40.

Abstract: A body compatible fiber optic sensor probe for invasive medical use is provided. The probe includes at least one sensing location at which the fiber is configured to provide at least one detectable changeable optical property responsive to strain within the fiber, and at least one sensing element which undergoes a volumetric change in response to an in body parameter to be sensed. The sensing element is coupled to the fiber in such a way that the volumetric change induces strain within the fiber so as to vary the detectable optical property or properties.

Abstract: A chemical sensing probe comprises an optical fiber or may be mounted on an optical fiber. The probe has a chemically sensitive measuring material which exhibits a change in volume and/or a change in refractive index in the presence of a given chemical. The change in volume and/or refractive index gives a change in an optical path length through the probe which can be measured interferometrically.