Large volume freezing in experimental hepatic cryosurgery. Avoidance of bleeding in hepatic freezing by an improvement in the technique.

In experiments on the dog's liver, large volumes of tissue were frozen by pouring liquid nitrogen onto the liver surface. There were no complications and no death from the procedure. Safety was produced by covering the liver surface with one to three layers of dacron velour cloth impregnated with a water-soluble jelly. The protective action of the gel-cloth was due to splinting of the liver capsule and to a more uniform and slower rate of freezing. The tissue became necrotic and over several months was replaced by dense fibrous tissue and ultimately resorbed. Although bleeding has been prevented, the problem of limitation of depth penetration remains as a hindrance to utilization in the treatment of hepatic tumors.