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

Síndrome com crises de migrânea tipo acidente vascular cerebral após radioterapia (SMART)

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 radiation¹. 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 occur².

Figure
Axial T1-weighted post-contrast MRI brain image demonstrates unilateral diffuse gyriform cortical enhancement with associated grey matter thickening on axial FLAIR imaging in the left parietal/occipital lobes (A and B). Follow-up MRI brain (16 days later) showed completed resolution of the cortical enhancement (C) and improvement of the FLAIR abnormality (not shown).

References

• ¹
  Kerklaan JP, Lycklama a Nijeholt GJ, et al. SMART syndrome: a late reversible complication after radiation therapy for brain tumors. J Neurol. 2011 Jun;258(6):1098-104. https://doi.org/10.1007/s00415-010-5892-x
  » https://doi.org/10.1007/s00415-010-5892-x
• ²
  Black DF, Morris JM, Lindell EP, Krecke KN, Worrell GA, Bartleson JD, et al. Stroke-like migraine attacks after radiation therapy (SMART) syndrome is not always completely reversible: a case series. AJNR Am J Neuroradiol. 2013;34(12):2298-303. https://doi.org/10.3174/ajnr.A3602
  » https://doi.org/10.3174/ajnr.A3602

Publication Dates

• Publication in this collection
  Mar 2019

History

• Received
  02 Aug 2018
• Reviewed
  04 Oct 2018
• Accepted
  20 Nov 2018