Fourth Ventricular AVM with Transdural Drainage

Arteriovenous malformations (AVMs) of the fourth ventricle are exceptionally rare subtypes of brainstem AVMs. This report illustrates the case of a young man who suffered intraventricular and subarachnoid hemorrhage. Angiography depicted a fourth ventricular AVM that was supplied by branches of the right posterior inferior cerebellar artery and drained via a posterior medullary midline vein into the marginal sinus and cervical radicular and nuchal veins. The drainage pattern is highly uncommon and constitutes a particular challenge for the operative approach.