cryosurgery /-sur″jərē/ [Gk, kryos + cheirourgos] , use of subfreezing temperature to destroy tissue. Cryosurgery is performed in the destruction of the ganglion of nerve cells in the thalamus in the treatment of Parkinson’s disease, in the destruction of the pituitary gland to halt the progress of some kinds of metastatic cancer, and in the treatment of various cancers and lesions of the skin. The process is also used in ophthalmology to cause the edges of a detached retina to heal and to remove cataracts. The coolant is circulated through a metal probe, chilling it to as low as −160° C (−256° F), depending on the chemical used. The moist tissues adhere to the cold metal of the probe and freeze. Cells are dehydrated as their membranes burst; eventually they are discarded or absorbed by the body.
