Experimental results on the rewarming of a cryopreserved organ phantom in a UHF field.

We describe a UHF rewarming system which has been used to measure warming rates, and particularly the uniformity of warming on three orthogonal axes, in a rabbit kidney phantom 36 mm in diameter. The stabilizing effect is demonstrated of using an E-field directed along the temperature gradient (or normal to any surface of dielectric discontinuity). One hot spot remains unaccounted for. The average warming rates and power dissipation are related to the volumetric heat capacity of the phantom material at -30 degrees C.

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