Not All Patients with a Headache need a CT Scan, but they should be Listened to, and also with a Stethoscope: A Report of a Large Arteriovenous Malformation with a Loud Cranial Bruit.

Background: Arteriovenous malformations (AVMs) are abnormal direct connections between arterial and venous systems, without an interposed capillary bed. This permits high-flow arteriovenous shunting, which precipitates structural changes in the afferent and efferent vessels, namely arterial smooth muscle hyperplasia and thinning of venous walls. Patients with intracranial AVMs typically present with a haemorrhage, headache or seizure.