Venous sinus stenting

Large veins inside the skull, called venous sinuses, drain blood from the brain. When one is narrowed (stenosed), pressure can build up, which can cause a whooshing sound in time with your heartbeat (pulsatile tinnitus) and, in some people, a condition called idiopathic intracranial hypertension (IIH), where pressure inside the head is raised for no clear reason. IIH causes headache that is often worse lying down or in the morning, brief greying-out of vision, double vision and a whooshing noise in the ear, and if untreated it can damage vision permanently. Not all tinnitus is due to sinus stenosis: most tinnitus has other causes, and a doctor needs to look for the cause of pulsatile tinnitus, which can include abnormal vessels, not just a narrowed vein. Assessment includes an eye examination, MR or CT scans of the veins, and sometimes a catheter test that measures pressure across the narrowing. In IIH, weight loss and medicines come first. Venous sinus stenting places a small mesh tube in the narrowed vein to hold it open, and it is considered for selected people with a proven narrowing and pressure difference, usually when other treatment has not worked. Stenting often improves swollen optic nerves and pulsatile tinnitus, while headache improves less reliably; the evidence so far comes more from observational studies than from randomised trials, so certainty is limited and trials are ongoing. Risks include bleeding, a clot in the stent, headache, and narrowing next to the stent, and you take blood-thinning tablets for a time afterwards. See an eye specialist urgently if your vision changes.