[Symptomatic radiation necrosis 10 years after gamma knife surgery for arteriovenous malformations: a case report].

We present a case of symptomatic radiation necrosis after gamma knife surgery for arteriovenous malformations (AVMs). Initially, at the age of 30 years the patient was treated with gamma knife surgery. Angiography performed 2 years after radiation therapy revealed that the AVMs were completely obliterated. Five years later, the patient had a generalized convulsion and a computed tomography (CT) scan showed a cystic formation in the irradiated area. The patient was treated with a cyst-peritoneal (CP) shunt. Thereafter, the patient seemed to be cured, but 5 years after CP shunt treatment, the patient had right hemiparesis, agraphia, and right hemianopsia. Magnetic resonance imaging (MRI) revealed radiation necrosis in the left parietooccipital region and midline shift of the brain. The patient was operated on and the hyalinized nidus and CP shunt tube were removed. The patient fully recovered from the symptoms and resumed work.