Transient Visual Hallucinations due to Posterior Callosal Stroke

Background: Stroke of the corpus callosum is uncommon, known to be associated with disturbance of higher brain function including hemifacial metamorphosia, but has never been reported to cause visual hallucinations. Methods: We report on a case of a 71-year-old woman who presented to the emergency department with a 3-day history of intermittent, formed visual hallucinations in the left visual field, often triggered by eye closure or darkness. Results: Neurologic examination was normal including cognition and affect, visual acuity, and visual fields. Electroencephalogram was normal. Magnetic resonance imaging scan of her brain showed a small stroke in the right inferior forceps major. Hallucinations resolved on day 2 of her admission, and she remains well more than a year later. Conclusions: This is the first report of transient visual hallucinations after a callosal stroke, which is an uncommon territory of stroke and a rare presentation of stroke.