Endovascular treatment of cranial arteriovenous malformations and dural arteriovenous fistulas.

Pial arteriovenous malformations (AVMs) and dural arteriovenous fistulas (DAVFs) are high-flow vascular lesions with abnormal communications between the arterial and venous system. AVMs are congenital lesions, whereas DAVFs are considered acquired lesions. Both can cause significant morbidity and mortality if they rupture and result in intracranial hemorrhage. The primary goal of treatment is to eliminate the risk of bleeding or at least decrease it. Because the epidemiology, clinical presentation, and classification of AVMs and DAVFs have been covered in previous articles in this issue, the authors only briefly touch on these subjects as they relate to endovascular treatment.