頭蓋照射10年後の放射線療法後脳卒中様片頭痛発作（SMART）症候群：診断上の課題

Stroke-like migraine attacks after radiation therapy (SMART) syndrome is a rare, late complication of cranial radiotherapy characterized by recurrent neurological symptoms, which may include headaches, hemiparesis, aphasia, seizures and confusion. The condition typically manifests years after radiation exposure, with magnetic resonance imaging (MRI) showing transient, reversible cortical abnormalities in previously irradiated regions. Although often self-limiting, neurological recovery may be incomplete in some cases. We present the case of a 64-year-old elderly male with a prior history of cranial irradiation received in 2015 who was admitted with abnormal body movements. Initial blood investigations and a non-contrast CT head were unremarkable. The MRI brain scan demonstrated deep white matter ischemic changes with no new focal lesions compared to a prior scan. Cerebrospinal fluid analysis was normal. Electroencephalography revealed focal onset seizures with secondary generalization. Following neurology review, antiepileptic therapy was optimized. Based on the clinical history, radiological findings, and seizure disorder, a diagnosis of SMART syndrome was made. The patient gradually improved his level of consciousness with a decrease in seizure activity with good neurological recovery.