Dural and carotid-cavernous fistula embolisation

A fistula is an abnormal direct link between an artery and a vein. A dural fistula sits in the covering around the brain or spinal cord, while a carotid-cavernous fistula sits behind the eye, where the carotid artery runs through a vein-filled space. The symptoms depend on where it is. Near the ear, it can cause a whooshing sound in time with your heartbeat (pulsatile tinnitus) and sometimes headache. Behind the eye, it can cause a red, swollen or bulging eye, double vision, eye pain or blurred vision. In the spine, it can cause slowly worsening leg weakness or numbness and bladder or bowel problems; this is often mistaken for other conditions, so tell your doctor if it is getting worse. Diagnosis uses MRI or CT scans, and often a catheter angiogram, which shows the abnormal flow best. In most cases a catheter is guided into the fistula and a liquid, coils or both are used to close the connection, while some low-risk fistulas are only watched. Risks include stroke, bleeding, and nerve or vision problems. Fistulas can return, so you will have follow-up imaging. Some fistulas can bleed. Call emergency services for a sudden severe headache.