Cerebrospinal fluid leakage after gamma knife radiosurgery for skull base metastasis from renal cell carcinoma: a case report.

We report a rare case of cerebrospinal fluid (CSF) leakage after radiosurgery for skull base metastasis from renal cell carcinoma. A mass invading the left petrous bone and sphenoid sinus was treated with gamma knife radiosurgery, and CSF rhinorrhea developed 4 months after the procedure. The CSF leak was successfully controlled by endoscopic sinus surgery. CSF leakage may develop as a rare complication after radiosurgery for skull base lesions, and the endoscopic repair technique is a useful therapeutic method.