Experimental results of ultrasonic monitoring of cryotherapy on in vitro skin samples of domestic pig

One of the principal difficulties encountered in cryosurgery is to know the extent and depth of the frozen tissue boundary during the freezing process and the extent of the cryonecrosis in the postfreezing period. The authors seek to evaluate echography possibilities in monitoring the freezing process during cryotherapy in dermatology. The first experimental results of ultrasound monitoring of the freezing process with a 15-MHz transducer on in vitro pig skin are described. It is shown that it is possible to easily detect the frozen region depth boundary. Conventional linear filtering of the echographic signals can be very useful for SNR enhancement in the detection of a target signal drowned in speckle noise