Magnetic Resonance Imaging of an Angiographically Occult Arteriovenous Malformation

—Case Report—

Abstract

The authors report a case of histologically confirmed cerebral arteriovenous malformation (AVM) in which cerebral angiography demonstrated only mass effect. Magnetic resonance (MR) imaging yielded valuable preoperative diagnostic information. T₁ and T₂-weighted MR imaging demonstrated an area of mixed signal intensity with a mossy appearance, evidence of a hematoma around the mass, and spots of zero signal intensity within the mass, suggesting the presence of vessels with accelerated blood flow.