The Study of Applying Method and Time for Improving Treatment Result in Cryosurgery: Theory of Selective Cryolysis / 대한피부과학회지

ABSTRACT

BACKGROUND: Cryosurgery uses freezing temperatures to achieve specific effects on tissues, and this method has been used to treat various skin diseases for the last five decades. The modern cryosurgery is especially effective on the treatment of benign, premalignant and malignant lesions including keloid, hypertrophic scar and pigmented disease such as Ota nevus. The results of cryosurgery depend on such factors as types of cryogen, freezing and thawing time, and numbers of the freezing-thawing cycle. OBJECTIVE: The purpose of this study is to show differences among groups of disease, sites of treatment and applying methods through comparing freezing and thawing time. And specifying the optimum applying methods for the treatment of each specific disease is studied. METHOD: To attain the goal of the study, operation records of 224 patients, who received cryosurgical treatment at the Ewha Woman's University Dongdaemoon Hospital, have been analyzed. RESULTS: 1. The numbers of male and female patients of selected group were 74 and 150, respectively, and their ages between 2 and 54 years. Among the group, 42 patients had epidermal pigmentary disease, 77 had dermal pigmentary disease and 105 had scars. 2. Ratios of TT(thawing time) to FT(freezing time) were significantly different among groups of disease(p<0.05). 3. Ratios of TT to FT were significantly different among groups of treatment site(p<0.05). 4. Ratios of TT to FT showed great difference between the group of rolling method applied and one of pressure method applied(p<0.05). CONCLUSION: The output of this study indicates that the result of the cryosurgery tends to be heavily influenced by the surgical method that is employed. It also proves that the pressure method tends to inflict more severe cryoinjury on the tissues than the rolling method. Each different tissue shows different sensitivity to the cold injury, and the longer the thawing time is, the more cryoinjury of tissues occurs. Therefore, to achieve the maximum therapeutic result while minimizing the undesired effect, adequate surgical method should be selected and applied to each specific disease. This concept is introduced in this study as "Theory of Selective Cryolysis.".