Vascular malformations are lesions where the traditional network of capillaries linking arteries and veins are lacking. Patients usually present with bleeding, pain, disfigurement and tissue expansion and destruction. High flow lesions can be challenging to manage in the head and neck region especially with potentially difficult access and bleeding. The lesion could be classified with the Schobinger clinical staging system which assesses severity and progression of the lesion. The authors only reserve intervention for patients who are Schobinger stage 2 and above. Preferred investigation for suspected AVM would involve Magnetic Resonance (MR) angiography which would show the size and the lesion in relation to surrounding structures aiding operative planning. The authors advocate a multidisciplinary team approach to managing these lesions. Endovascular intervention and subsequent surgical excision is a well-described intervention for lesions that are well-localised or have a well-localised nidus. However, challenges remain for diffuse lesions that have complications including recurrence and cosmetic deformity. Traditional agents used for embolisation include coils and plugs. However, there are new agents such as non-adherent copolymers dissolved in a solvent giving it greater flow such as Onyx® and PHIL™. The agent hardens gradually when in contact with blood allowing more working time and more time for injection. This allows plugging of the nidus completely. The potential complications of using this agent include local and perivascular irritation that may also stain the skin. As with any endovascular procedure, misplacement of agents could cause ischaemia to normal structures and may result in blindness or stroke. In summary, the authors report their experience in managing AVMs and advocate preoperative embolisation targeting the nidus of the lesion with subsequent surgical excision as the treatment of choice, as embolisation helps reduce intraoperative bleeding and delineates the lesion while subsequent surgical excision helps reduce the risk of recurrence.
Managing high flow head and neck arteriovenous malformations (AVM)
Reviewed by Wai Sum Cho
Arterioveneous malformations of the head and neck: current concepts in management.
