A fistula is an abnormal communication between two structures of the body. Dural arterio-venous fistulas occur between arteries and veins present in the dura (fibrous covering of your brain). This causes high-pressure arterial blood to enter the venous system, which is not created to handle such pressure and becomes congested. This hinders the blood circulation in the brain and can lead to dysfunction.
Dural arterio-venous fistulas may occasionally develop in areas of previous trauma, surgery, infection or clot formation, but is often seen without any precedent. Small fistulas do not usually show any symptoms. Growing or large fistulas located in the dura close to the ear are associated with whooshing sounds, following the pattern of your heart beat, while those located close to the eyes lead to bulging, redness and high pressure in the eyes. Other symptoms can include headache, seizure, stroke, concentration and memory problems, psychosis, hallucinations or other psychiatric problems.
When you present to the clinic, your doctor will review your symptoms and diagnose your condition with the help of an angiogram which uses an X-ray detectable dye to study the blood vessels in your head.
The main aim of treatment is to close the fistula. Your doctor may perform endovascular embolization which involves inserting a catheter in your groin and threading it up to reach your fistula. A blocking agent is introduced through it to close the fistula. Radiosurgery is another method that uses highly focused radiation to damage and close fistulas that are difficult to access. Open surgery with microsurgical resection is another alternative for inaccessible fistulas, which involves removing a section of your skull to isolate and resect a fistula.