Dural Arteriovenous Fistulas
Dural arteriovenous fistulae (AVF) are blood vessels that represent abnormal connections between arteries and veins that are found in the covering of the brain. This covering is known as the dura, hence the name. There is a direct connection between the arteries and the vein without any vessels between.
These fistulae or abnormal connections usually develop over time and can occur after trauma, infection or thrombosis (clotting-off) of veins in the dura. The fistula may cause abnormal noises in the head due to the high flow of blood. They can also cause headaches or result in bleeding into the brain.
The treatment is similar to those available for AVMs and can include embolization, surgery, and in some cases radiosurgery. Embolization is often used as the primary therapy to treat this problem. Embolization is performed by placing a tiny catheter directly into the AVF. Embolic material is then injected into the blood vessel to block them up. The embolic material leaves the catheter as liquid and solidifies within the AVF blood vessel to block it up. Sometimes coils are also used to block up the AVF.
DAVF pre-treatment
Angiogram from a patient with a dural fistula behind the ear (blue arrows outline dilated vein coming from the fistula). Patient was suffering from continuous whooshing sounds that made it hard to sleep and work.
DAVF post-treatment
Angiogram performed after the same patient had endovascular treatment, which now shows the fistula has been completely occluded. The whooshing sound disappeared completely with this treatment.
