Unilateral Perioral, Thumb, and Thenar Numbness Secondary to Acute Thalamic Infarct.

Lacunar infarcts are small, deep infarcts that occur in subcortical regions of the brain and can result in pure sensory stroke syndromes, ataxia, and dysarthria. The most common predisposing etiology is small-vessel lipohyalinosis or microatheroma formation usually secondary to diabetes mellitus or systemic hypertension. We report a patient who presented with cheiro-oral syndrome (COS) with left sided perioral, thumb, and thenar numbness after an acute lacunar infarct of the right thalamus.