A 30-year-old man with a history of acute lymphocytic leukemia in remission presented to the University of Virginia with blurry vision and blind spot enlargement in the right eye and was found to have leukemic infiltration of the optic nerve. Photography showed severe disc edema and hemorrhage. Visual acuity was 20/400, decreased from 20/20 previously. Magnetic resonance imaging of the orbits showed enhancement of the right optic nerve head. The patient completed systemic chemotherapy treatment 3 months prior and had a negative systemic workup, including lumbar puncture. Emergent external beam radiation therapy to a dose of 24-30 Gy was initiated. At 1 month’s follow-up examination, he had visual acuity of 20/20 and significant regression of optic disc infiltration on funduscopy.