Delayed Brain Cyst Formation After Gamma Knife Anterior Capsulotomy

Gamma Knife ventral anterior capsulotomy is an effective option to treat refractory obsessive-compulsive disorder. Although well tolerated, complications can develop years after radiosurgery. We describe a case in which abnormal complications induced by very high doses of radiation evolved.

A 55-year-old man with refractory obsessive-compulsive disorder was treated with Gamma Knife ventral anterior capsulotomy using a dose of 180 Gy. His obsessive-compulsive symptoms improved, but his condition evolved with a manic episode, cognitive memory changes, visual hallucinations, confabulation, and frontal lobe symptoms. Magnetic resonance imaging showed brain edema in the left hemisphere and a 6-mm brain cyst in the right hemisphere at postoperative month 20.

This case shows the consequences of affecting more fibers related to the anterior frontal region than intended with a radiosurgical procedure and illustrates the importance of careful clinical and imaging follow-up after Gamma Knife ventral anterior capsulotomy.