Recurrent Positional Vomiting due to Cerebellar Infarction and Obstructive Hydrocephalus.

An 80-year-old woman presented with the sudden onset of vertigo and vomiting and was diagnosed with acute cerebellar infarction. Twelve days after the onset, she experienced positional vomiting, predominantly in the lying-down position, triggered by postural changes with immediate or delayed onset. Over 1 month, 23 episodes of vomiting occurred. Brain computed tomography revealed edema in the infarcted area, fourth ventricular outlet compression, and lateral ventricular enlargement. These findings suggest that fluctuations in intracranial pressure are associated with intermittent obstructive hydrocephalus exacerbated by the patient's posture. This case highlights the importance of considering postural triggers in patients with recurrent vomiting associated with cerebellar infarctions.