Huang Deborah, Dixit Karan S
Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
Malnati Brain Tumor Institute, Northwestern University, Chicago, IL, USA.
Neurohospitalist. 2022 Jul;12(3):567-570. doi: 10.1177/19418744221102290. Epub 2022 May 15.
Stroke-like migraine attacks after radiation therapy (SMART) syndrome is a rare, delayed complication of cranial radiation therapy that consists of migraine-like headaches and focal neurologic deficits such as visual loss, aphasia, hemiparesis, hemisensory loss, and unconsciousness. SMART syndrome may be mistaken for tumor recurrence, radiation necrosis, and stroke. Timely recognition of SMART syndrome prevents unnecessary brain biopsies and enables appropriate anticipatory guidance. We present a 38 year-old right handed male with new headaches, vertigo, visual symptoms, and left-sided paresthesias. Neuroimaging revealed a heterogeneously enhancing mass with invasion into the transverse sinus, diagnosed as an epithelioid hemangioendothelioma by surgical pathology. After resection, the patient underwent proton beam radiation for maximal tissue-sparing. Six months later, he developed radiation necrosis. After another year, he developed recurrent headaches with transient language difficulties and blurry vision during each headache. Neuroimaging was consistent with SMART syndrome, and the patient was started on valproate. Verapamil was added after a second attack. The patient's headaches improved, but he remains dyslexic. Subsequent imaging shows resolution of gyriform contrast enhancement and continued left temporo-occipital T2/FLAIR hyperintensity. We present a case of early SMART syndrome following proton beam radiotherapy, as well as the dual occurrence of radiation necrosis and SMART syndrome in this individual. Radiation necrosis and SMART syndrome are known complications of radiotherapy, with the latter less well-described. We discuss a possible shared pathophysiology involving endothelial cell dysfunction and impaired cerebrovascular autoregulation, and we question whether proton RT increases risk of early SMART syndrome development.
放疗后类卒中偏头痛发作（SMART）综合征是一种罕见的、延迟性的颅脑放疗并发症，表现为偏头痛样头痛和局灶性神经功能缺损，如视力丧失、失语、偏瘫、偏身感觉丧失和意识丧失。SMART综合征可能被误诊为肿瘤复发、放射性坏死和卒中。及时识别SMART综合征可避免不必要的脑活检，并能进行适当的预期指导。我们报告一例38岁右利手男性，出现新发头痛、眩晕、视觉症状和左侧感觉异常。神经影像学显示一个不均匀强化的肿块侵犯横窦，手术病理诊断为上皮样血管内皮瘤。切除术后，患者接受质子束放疗以最大程度保留组织。6个月后，他出现放射性坏死。又过了一年，他出现复发性头痛，每次头痛时伴有短暂的语言困难和视力模糊。神经影像学表现符合SMART综合征，患者开始服用丙戊酸盐。第二次发作后加用维拉帕米。患者的头痛有所改善，但仍有阅读障碍。后续影像学显示脑回状对比增强消失，左侧颞枕叶T2/FLAIR高信号持续存在。我们报告一例质子束放疗后早期SMART综合征病例，以及该患者同时出现放射性坏死和SMART综合征的情况。放射性坏死和SMART综合征是放疗已知的并发症，后者的描述较少。我们讨论了一种可能涉及内皮细胞功能障碍和脑血管自动调节受损的共同病理生理学机制，并质疑质子放疗是否会增加早期SMART综合征发生的风险。
