Scalp Arteriovenous Malformation with Concomitant, Flow-Dependent Malformation and Aneurysm

Scalp arteriovenous malformations (sAVMs) are well-described congenital abnormalities for which co-occurrence with other vascular pathologies significantly alters management strategies. The authors describe a case in which congenital sAVM was found with concomitant intracranial, flow-dependent vascular malformation and schizencephalic developmental anomaly.

A 21-year-old man presented with a right-sided bruit and an enlarging palpable, pulsatile scalp mass. Magnetic resonance imaging demonstrated a 5-cm right sAVM and an azygos anterior cerebral artery (ACA) feeding a 2-cm parafalcine vascular anomaly, as well as an unruptured 3-mm, flow-related, distal ACA aneurysm. sAVM feeders were catheterized and embolized with Onyx 18. During resection of the right frontal scalp lesion, dissection below the pericranium was developed to expose the low-flow extracranial sAVM. A supratrochlear arterial feeder and the vascular nidus were coagulated, but radical resection was avoided to prevent scalp necrosis. An anterior right frontal parasagittal craniotomy and dural opening were performed. A developmental anomaly of the right superior frontal gyrus was noted, and a dense vascular network within the anterior parafalcine fold was excised and coagulated. The distal ACA aneurysm was cauterized and wrapped to preserve the parent artery. The patient made an excellent recovery without neurologic deficits.

A review of the literature demonstrated a variety of endovascular and open surgical treatments with limited consensus on standard care. While sAVMs have been described in the literature, the combination of the diverse conditions seen in this case is unique.