SMART syndrome: a case report

Acta Neurol Belg. 2023 Jun;123(3):1137-1140. doi: 10.1007/s13760-022-01965-6. Epub 2022 May 19.

Abstract

Introduction: Stroke-like migraine attacks after radiation therapy (SMART) syndrome, is a late complication of brain radiotherapy (1). Symptoms are commonly subacute in onset and involve migraine type of headache, seizures, focal neurologic deficits (2). Magnetic resonance imaging (MRI) findings are usually unilateral and posterior predominant cortical-subcortical hyperintensity, swelling and prominent gyriform (cortical and leptomeningeal) gadolinium enhancement in the areas of the brain that underwent irradiation with or without diffusion restriction (1). There is no standard treatment protocol for SMART syndrome. Antiepileptics and corticosteroids are commonly used drugs.

Case report: A 65 years old woman was diagnosed with breast cancer with brain metastases and treated with more than 50 Gy brain radiotherapy. The patient presented with acute right-sided weakness and numbness, episodic myoclonic jerking of the right arm and leg, and gait instability five months later. MRI and magnetic resonance angiography of the brain with gadolinium revealed left parietooccipital cortical diffusion restriction and accompanying dilatation of the left posterior cerebral artery as new findings. Computed tomography (CT) perfusion revealed increased perfusion in the affected area. The patient was diagnosed with SMART syndrome.

Management and outcome: The patient was treated with dexamethasone (16 mg/day) and anticonvulsant therapy. Myoclonic seizures had almost completely remitted. However, her cognitive impairment persisted, then the patient was arrested because of aspiration a month later.

Discussion: Besides confirming SMART syndrome, diagnostic investigations are also important to exclude other etiologies. Posterior reversible encephalopathy syndrome, post-ictal changes, meningoencephalitis, and cerebrovascular diseases are radiological differential diagnoses considered (3). Proper and early diagnosis of SMART syndrome is significant in preventing unnecessary aggressive approaches and appropriate treatment to avoid lesions of sequela.

Keywords: Brain radiation; Stroke-like migraine attacks after radiation therapy.

Publication types

  • Case Reports

MeSH terms

  • Aged
  • Brain / diagnostic imaging
  • Brain / pathology
  • Contrast Media
  • Female
  • Gadolinium / therapeutic use
  • Humans
  • Magnetic Resonance Imaging / methods
  • Migraine Disorders* / diagnosis
  • Posterior Leukoencephalopathy Syndrome* / complications

Substances

  • Contrast Media
  • Gadolinium