Arteriovenous Fistula (AVF) is an abnormal connection between an artery and a vein. The normal blood circulation involves flow of blood from artery to capillaries to a vein. With an AV fistula, capillaries are bypassed making a direct flow between an artery and a vein which ultimately reduces the blood supply to the tissues otherwise supplied by the normal capillaries. AV fistula is an acquired lesion which means someone is not born with it but acquired later in life due to infection, traumatic injury, tumor, surgery or in some cases without any precipitating event. Please read more in the Dural Arteriovenous Malformation (DAVF) chapter.
AV fistula can be treated by endovascular embolization, open surgery or by combination of both methods. Endovascular embolization is a minimally invasive procedure in which endovascular surgeon makes a small incision in groin area. The surgeon then passes the navigating tube through the femoral artery and advances up into the artery which is forming AV fistula. Through this navigating tube, the surgeon then injects an embolizing agent such as glue like substance (usually onyx), micro coil or a metallic stent to physically block the blood supply of AV fistula. In some cases, open surgery (Craniotomy or Laminectomy) is required after endovascular treatment to physically remove the AV fistula.
Please see section of neurosurgical procedures for more information on open surgical treatment of brain and spine AV fistula.