Department of Neurology, Weill Cornell Medicine & New York-Presbyterian, New York, NY, USA.
Department of Neurology, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
Curr Pain Headache Rep. 2021 Mar 24;25(5):33. doi: 10.1007/s11916-021-00946-3.
SMART syndrome is a delayed complication of cranial irradiation that can be misconstrued as tumor recurrence or some other intracranial neurological disease. Recognition of this clinical syndrome is imperative as it can obviate the need for invasive diagnostic testing and can provide reassurance to both the patient and their loved ones.
SMART syndrome is generally considered a reversible clinical syndrome; however, neurological deficits may become permanent. Pathophysiology of SMART syndrome may involve cerebrovascular autoregulation impairment, neuronal dysfunction leading to trigeminovascular system impairment and/or cortical spreading depression, and seizures. In addition to MRI brain with gadolinium, other imaging modalities, such as CT perfusion, MR perfusion, MR spectroscopy, and FDG PET/CT, aid in arriving to the diagnosis sooner. Patients should also undergo electroencephalogram in order to promptly identify and treat seizures. There are currently no clear guidelines on how to effectively treat SMART syndrome, but treatment may involve anti-seizure medication, anti-hypertensives, anti-platelet, and steroid therapy. This review provides a comprehensive understanding of the clinical characteristics of SMART syndrome from presentation to diagnostic evaluation. We also discuss radiographic features and treatment strategies for this rare disease. With increased radiotherapy utilization, prompt clinical recognition of SMART syndrome and further development of a comprehensive diagnostic approach to SMART syndrome utilizing newer radiographic modalities as well as treatment algorithms to effectively treat this clinical condition will be imperative.
SMART 综合征是颅脑放疗的迟发性并发症,可能被误诊为肿瘤复发或其他颅内神经疾病。认识到这种临床综合征至关重要,因为它可以避免不必要的侵入性诊断性检查,并为患者及其家属提供安心。
SMART 综合征通常被认为是一种可逆的临床综合征;然而,神经功能缺损可能会永久存在。SMART 综合征的发病机制可能涉及脑血管自动调节功能障碍、神经元功能障碍导致三叉神经血管系统功能障碍和/或皮质扩散性抑制,以及癫痫发作。除了钆增强 MRI 脑部成像外,其他成像方式,如 CT 灌注、MR 灌注、MR 波谱和 FDG PET/CT,有助于更快地做出诊断。患者还应进行脑电图检查,以便及时发现和治疗癫痫发作。目前尚无明确的治疗 SMART 综合征的指南,但治疗可能包括抗癫痫药物、抗高血压药物、抗血小板药物和类固醇治疗。本综述从发病到诊断评估全面了解 SMART 综合征的临床特征。我们还讨论了这种罕见疾病的影像学特征和治疗策略。随着放疗的应用增加,及时认识 SMART 综合征,并进一步开发使用新型影像学手段以及治疗方案来有效治疗这种临床疾病的全面诊断方法将至关重要。