Congenital Arteriovenous Malformation of the Scalp Involving the Orbit

Abstract

Background Arteriovenous malformations (AVMs) of the scalp are rare and infrequently encountered by the neurosurgeon. Case Description We report a unique case of a 42-year-old patient who presented with a progressive worsening of visual acuity in the right eye (lower quadrantanopia) and palpebral ptosis. Physical examination revealed a right exophthalmos and a right frontoparietal scalp soft swelling when the patient was in the supine position. Neurologic work-up showed a scalp AVM extending into the orbit and connected to an intraorbital cavernous angioma. The patient was treated with a frontotemporal craniotomy and decompression of the orbit. Conclusions In the rare case of intraorbital extension of a scalp AVM, neurologic symptoms may appear when the size of the vascular malformation increases with age. The aims of surgery should be decompression of the orbit and aesthetic preservation, rather than complete excision. A review of the literature is also provided.

A Rare Case of Scalp Arteriovenous Malformation in an Adolescent Patient

“…Approximately 10% to 20% of cases of AVMs of the scalp occur after a traumatic head injury [ 2 , 16 ]. The majority of the available literature states that because of the absence of trauma history, scalp AVMs are classified as either congenital or idiopathic [ 17 ]. According to some experts, the distinction between congenital and idiopathic AVMs is made based on how long the anomaly has existed i.e., since birth [ 4 ].…”

“…Other than for cosmetic reasons, the goal of treating these lesions is to avoid the long-term effects of the ongoing shunting from the arterial system (high pressure) into the venous system (low pressure) [ 11 ]. These lesions are challenging to treat due to their multiplex vascular anatomy and the degree of the venous extension in the scalp [ 17 ]. Excision of the entire scalp AVM necessitates a thorough understanding of the nature of the malformation including the anatomy of the feeding vessels, draining veins, and the nidus [ 7 ].…”