Cirsoid aneurysm of the scalp.

A 29-year-old man with a pulsatile scalp swelling is presented. The clinical diagnosis of a cirsoid aneurysm was confirmed on computed tomography of the brain and selective cerebral angiography. It is important to detect veins draining from the aneurysm into the intracerebral venous system, as percutaneous occlusion of the aneurysm may be possible in their absence.