Endovascular treatment for scalp arteriovenous fistulas: prospects and dilemmas

Scalp arteriovenous fistula (AVF) is an anomalous arteriovenous connection without a capillary bed. For symptomatic scalp AVFs, an appropriate treatment must be chosen. Currently, endovascular treatment (EVT) can serve as an alternative to surgical excision. However, EVT of scalp AVFs constitutes a challenge. A standard EVT strategy for scalp AVFs has not yet been established. Therefore, a review of current research on EVT for scalp AVFs is essential. In this review, the following issues were discussed: scalp vessel anatomy; etiology, angioarchitecture and classification of scalp AVFs; EVT principles and techniques; and EVT complications and prognosis. In addition, we attempted to propose a feasible grading system with 4 grades. Based on the literature review and our experience, we found that scalp AVFs have a complex angioarchitecture, which made EVT only possible in specific cases with low-grade scalp AVFs. EVT can be performed by transarterial or transvenous embolization. Direct puncture embolization can also be used for scalp AVFs. Complete occlusion of scalp AVF by EVT had low complication and recurrence rates and a good prognosis.