Cryosurgery – Frozen Medicine
The term cryosurgery or cryotherapy indicates the use of deep cooling or freezing devices to treat the skin changes. It is liquid nitrogen that is mostly used in dermatology for local destruction and removal of the unwanted skin changes. Skin is generally rather resistant to freezing because of its high blood supply and the frozen skin surface tissue acts like an isolator protecting the deeper layers from freezing. Even though the exact mechanism of cryo-necrosis is not well-known, it is recognized that during this process the mechanical cell damage occurs because of formation of ice crystals, then osmotic changes, thermal cell shock, protein denaturation of cell membrane and vascular pathways and finally necrosis or disintegration of deep frozen tissue.
Indications for Cryotherapy
Cryotherapy is used for many benign and malign skin changes such as: viral warts of all kinds and localizations, genital warts (condylomata), molusca contagiosa (viral infection similar to warts caused by the virus of the same name), seborrheic or senile warts, cutaneous horns (cornu cutaneum), some kinds of skin tumors, keloids, hypertrophic scars, epidermal and other types of moles, smaller hemangiomas, lymphangiomas, leukoplakia, solar (actinic) kertosis, old age spots (lentigo senilis), etc.
Liquid nitrogen is the most frequently used agent in the world’s dermatology. Its temperature is -195.8 C and it could be purchased at technical gas manufactures or large users and suppliers. It is preserved in special metal containers where it could last for even two months. Before its use in practice it is transfused into smaller thermos bottle that keeps its temperature for two working days. Liquid nitrogen represents the coolest technique of cryosurgery since it freezes the skin lesions faster, fuller and more effective than any other freezing agents (some carbons, nitrogen oxides, etc.) Also, it could be easily applied using different high control and ultra-precise applicators for each individual skin change.