Stroke-like migraine attacks after radiation therapy (SMART) syndrome

Abstract

A 33-year-old, right-handed male with a left occipital hemangiopericytoma treated with resection/radiation (60 Gy) with resultant focal epilepsy, presented with severe left-sided headache, expressive aphasia/right homonymous hemianopsia and right-sided hemisensory deficits. The EEG was unremarkable. Initial MRI brain scans are shown in Figures A and B. He improved with analgesics and returned to his baseline in two weeks. The MRI was repeated after 16 days ( Figure C). He was diagnosed with SMART syndrome, a rare and late complication of cranial irradiation 1,2 . The pathophysiology is still unclear. The process seems to be driven by cerebral hyperexcitability with impaired autoregulatory mechanisms and endothelial damage as a consequence of remote radiation 1 . Clinico-radiological features are challenging. Differential diagnosis includes tumor recurrence, leptomeningeal carcinomatosis, infection, vascular disorders, mitochondrial encephalomyopathy with lactic acidosis and stroke, hemiplegic migraine, posterior reversible encephalopathy and post-ictal MRI changes. Duration of symptoms is variable (hours to weeks). Most reported cases have had full clinical and radiological recovery with symptomatic management; however, incomplete recovery may occur 2 .