Arteriovenous Fistula at Scalp: Rapid Progression After Embolization of Contralateral Facial Arteriovenous Malformation

scalp is an abnormal connection between the feeding arteries and draining veins, without the normal capillary bed in the subcutaneous layer of the scalp. The draining veins may be grossly dilated and tortuous, and may show variceal dilatation (1-5). It is generally thought that AVM arises from multiple developmental defects causing the primitive capillary bed to fail to persist (6, 7). It is also thought that increased arterial pressure and flows lead to opening and dilatation of normal, latent AV shunts. Local ischemia and minor trauma also plays a role in enlargement of arteriovenous fistulas (AVF). Multiple craniofacial AVMs occurring in one patient are extremely rare, and only a few cases with multiple systemic malformations such as hereditary hemorrhagic telangiectasia or RenduOsler-Weber disease have been reported (8). Multiple craniofacial AVM may be hemodynamically related to each other by complex and intercommunicating vascular networks. This report describes a case with two craniofacial AVMs located at anatomically different regions. Interestingly, we found rapid progression of a scalp AVM after embolization of the other AVM on the contralateral side of the face. This may reflect a hemodynamic relationship between the AVMs located at anatomically different regions, and may suggest a new guideline in treatment of multiple craniofacial AVMs.