Hypersomnolence as the Presenting Feature of Thalamic Stroke

Posterior circulation stroke affecting thalamo-cortical arousal networks may present with increased sleepiness, with a lack of motor symptoms.Here, we present the case of a 41-year-old man with acute-onset hypersomnolence, without focal neurological deficits.The initial computed tomography (CT) brain was normal.Metabolic and infectious workup were negative.Magnetic resonance imaging (MRI) of brain was performed and revealed bilateral paramedian thalamic infarcts with hemorrhage and a left occipital infarct.MRI angiography demonstrated reduced flow in the posterior cerebral artery segments.This case highlights the prominent clinical feature of profound hypersomnolence in thalamic stroke and emphasizes how such patients are easily misdiagnosed when early CT imaging is unrevealing.Recognition of this pattern is critical to avoid delays in the diagnosis of thalamic infarction.