Neurologic Complications of Radiation Therapy.

Cranial radiation therapy (CRT) is used to treat a wide range of malignant and benign conditions and is associated with a unique set of risks and complications. Early complications from CRT include fatigue, skin reaction, alopecia, headaches, anorexia, nausea/vomiting, exacerbation of neurologic symptoms, serous otitis media, parotitis, and encephalopathy. Delayed complications include pseudoprogression, radiation necrosis, neurocognitive changes, cerebrovascular effects, migrainelike disorders, cataracts, xerophthalmia, optic neuropathy, hearing loss, tinnitus, chronic otitis, endocrinopathy, and secondary malignancy. This article presents an overview of clinically relevant neurologic complications for CRT, basic pathophysiology of radiation injury, and risk factors for neurologic complications.