Fig. 17. Delayed cerebral radionecrosis. The patient was a 44-year-old woman with chronic left visual loss to 20/70 who underwent stereotactic radiosurgery (single-session gamma). At 12 months, she suddenly lost all vision in both eyes. Enhanced magnetic resonance imaging: Left (coronal) and right (axial) sections show a hyperintense signal from the optic chiasm, tracts, and pituitary stalk (arrows). Asterisk, paraclinoid mengioma.