Principles of Cutaneous Cryosurgery: An Update

Skin diseasesIntroductionCryosurgery is the well-aimed and controlled destructionof diseased tissue by application of cold (table 1). It hasbeen shown to be effective and efficient in various skindiseases, provides high cure rates and good cosmetic resultswith a few contra-indications and low incidence of compli-cations 1.History of CryosurgeryThe first physician who used freezing to treat a dermato-logical disease was C. Gerhardt, a German dermatologistfrom Jena 2. In 1885, he published a paper on the treat-ment of cutaneous tuberculosis with cold. Gerhardt had builta system, in which the lesions were covered with ice blad-ders for 3 h twice a day. Four patients considerably im-proved after a 2- to 4-week treatment. In 1899, A.C. White,an American dermatologist from New York, used for thefirst time liquefied air to treat various skin disorders, such asverrucae vulgares, naevi, precancerous lesions and tumours.In the year 1905, M. Juliusberg, a dermatologist fromBerlin, introduced the term ‘cryotherapy’ for the treatmentof skin lesions with cold. He applied the first cryospray, asmall balloon filled with carbon dioxide released in spurts.Modern cryosurgery was born in the 1960s after liquidnitrogen became available, and closed-circuit devices work-ing with liquid nitrogen, freon gas and nitrogen protoxidehave been developed by the American neurosurgeons I.S.Cooper and A.S. Lee and their Italian colleagues V.A.Fasano, G. Broggi, T. de Nunno and P. Baggiore. Nowa-days, numerous sophisticated devices have been developedand commercialized, not only to preserve and deliver cryo-gens, but also to monitor temperatures in and underneaththe treated lesions, thus allowing a controlled and reliablecryosurgery of the diseased skin.CryobiologyThe biological changes that occur during and after cryo-surgery have been studied in vitro and in vivo and arecaused by reduction of tissue temperature and consequentfreezing 3–6. Tissue injury is induced by cell freezing andby the vascular stasis that develops in the tissue after thaw-ing. The cryoreaction is, therefore, characterized by the