An atypical stroke manifestation: Sleep disturbance in unilateral thalamic lesion

Abstract

Thalamic strokes may present with a wide variety of symptoms depending on their location, volume and lateralization. Hypersomnia is a less frequent manifestation, that has been associated with unilateral paramedian thalamic ischemic lesions. We report a case of a patient who presented to the emergency department (ED) with sudden onset of hypersomnolence. Initial head computed tomography (CT) showed no signs of acute ischemia. Follow-up head CT 24 h after thrombolysis exposed a hypodense lesion on the left ventromedial thalamic and mesencephalic regions, with corresponding T2/FLAIR hyperintensity and diffusion restriction on brain magnetic resonance imaging, confirming a recent ischemic stroke. Clinicians should be aware of the association between acute hypersomnia and strategic unilateral thalamic infarcts, particularly when the initial CT scan has no signs of acute ischemia.

Keywords

• Stroke
• Stroke chameleon
• Posterior circulation
• Thalamus
• Hypersomnia