Gamma Knife radiosurgery(GKS) is now believed as a safe and minimally invasive treatment modality in uveal melanomas whereas enucleation has long been the traditional treatment in the past.

     The authors report the long-term results of uveal melanomas treated by GKS between September 1993 and December 2006, and would like to analysis the temporal volume changes.

     Twenty-one patients with an uveal melanoma were enrolled in this study. They were 12 males and 9 females, and their mean age was 53.4 (24-79) years.

       The mean tumor volume was 0.94 (0.0006-5.83) cc and mean marginal dose was 41.1 (16.0-50.4) Gy. The median follow-up was 71 (56-156) months. The tumor was located in peripapillary (6 patients), midperiphery (14 patients), and ciliary body (1 patient).

     The mean volume change of tumor at 1 year after GKS was a 19% decrease. Tumor regression was achieved in 22 patients (81.5%) at 1 year after GKS. Overall 2-year survival rate was 90.5%. There were no statistically significant factors affecting to length of survival. There were 6 retinal detachments, 4 cataracts, 4 radiation retinopathies, and 1 glaucoma. Eventually, enucleation was performed in 4 patients and the eyeball retension rate was 81.0%.

     This was a retrospective study.

     GKS is a safe and minimally invasive method by which to treat uveal melanomas and could be an alternative treatment method to enucleation, especially when opposite eye-sparing treatments are not possible. It provides In addition, visual function might be preserved in selected cases with this treatment method.

     GKS cannot only preserve the eyeball and its potential visual function, but also achieve sufficient local control with temporal volume reduction to decrease the potential hematologic dissemination.