Several therapeutic methods have been employed in the management of localized granuloma annulare (GA), with varying degrees of success. We performed a prospective trial to evaluate the efficacy, cosmetic results, and safety of cryosurgical treatment in GA. Thirty-one patients with localized GA were treated by cryosurgery, using the contact method. Nitrous oxide (-86 degrees C) or liquid nitrogen (-196 degrees C) were used as refrigerants, and were applied with closed probes; each lesion was treated with one freeze-thaw cycle of 10-60 s per session. If necessary, treatment was repeated after 20-30 days. Resolution of the lesions was obtained in all patients, and in 25 of 31 patients (80.6%) they resolved after a single freeze-thaw cycle. Relapse occurred in only one of 11 patients who were followed for more than 2 years, and this occurred 16 months after treatment. Excellent cosmetic results were obtained in 14 of 28 patients who were eligible for evaluation (50%), and good results in 11 (39.3%). The cosmetic result obtained by cryosurgery with nitrous oxide was independent of the size of the lesion, whereas in the group of patients treated with liquid nitrogen a better cosmetic result was obtained with smaller lesions (comparison of lesions < or = 2.40 cm2 with those > 2.40 cm2; P = 0.04). The duration of the lesion, its location, previous treatment with another method, and the number of treatment sessions, did not have any influence on the cosmetic result. The treatment was generally well tolerated. Blister formation occurred in all patients.(ABSTRACT TRUNCATED AT 250 WORDS)