[A case of delayed facial palsy following gamma knife radiosurgery for intractable trigeminal neuralgia].

A 77-year-old woman with hypertension and senile depression had suffered from medically unresponsive trigeminal (left ophthalmic) neuralgia despite microvascular decompression surgery for twice. The patient underwent stereotactic gamma knife radiosurgery (77 Gy) for the neuralgia, resulting in pain relief. However, approximately 20 months after the radiosurgery, she developed left facial palsy with hydrodipsia, left xerophthalmia, and left facial hypesthesia.