The study objective is an objective assessment of the treatment outcome with a gamma knife radiosurgery (GKRS) in different types of supratentorial cavernous malformations on the basis of their sizes and clinical symptoms dynamic changes after the treatment.Materials and methods. GKRS outcomes in 145 patients with hemisphere cavernous malformations (58 male, 87 female, the mean age 43,3 ± 11,9) were analyzed by comparing the initial and control data in all the patients and the telephone interview of 91 (37 male, 54 female, the mean age being 42,2 ± 11,9) patients.Results. On the basis of the “CM size reduction” criterion the efficacy of GKRS in the first magnetic resonance imaging control was 70 %. It was comparable in type I and type II CMs (76,3 and 72,5 % accordingly), but it was evidently worse in type III CMs (p = 0,0032). Repeated hemorrhages were noted in 3 observations in deep type I CM. Totally, statistically evident dependence on CM size reduction (p = 0,0413) was obtained on the clinical efficacy criterion with initially developed symptoms, which in turn means does not prove its effectiveness in type III CMs. In epileptic syndromes accompanying CMs, the efficacy of GKRS was selective, and did not correlate with CM size reduction, but mostly depended on the genesis and course of epileptic seizures.Conclusion. GKRS appears to be a justified method of treatment for clinically compensated mobile patients with type I and type II CMs. The clinical effectiveness of GKRS in such patients is in no way inferior to open surgery and does not exceed the number of its complications. CM type III should be excluded from the objects of treatment by GKRS.Conflict of interest. The authors declare no conflict of interest.Informed consent. All patients gave written informed consent to participate in the study and for the publication of their data.