Venous sinus stenosis is a narrowing of the transverse or sigmoid sinus, large veins inside the skull that drain the brain, and it is among the commonest findable causes of pulsatile tinnitus, often treatable with a stent.
The narrowing matters because of what it does to the blood passing through it. A 2026 cohort study in Neurosurgical Review describes venous sinus stenosis as producing turbulent venous flow and raised pressure in the veins, and the turbulence, close to the ear, is heard as a whoosh in time with the pulse. That is a real physical sound with a source, which is why pulsatile tinnitus is investigated rather than managed like the steady kind.
How a venous whoosh behaves
A 2026 review of cerebral venous disorders in Frontiers in Neurology describes venous pulsatile tinnitus as a whooshing in one or both ears that may change with head position, with straining, or when the jugular vein on the same side is pressed, the last being its key clue to a venous source. The review advises that the examination include listening for a bruit, a sound the clinician can hear too, which would make it objective tinnitus.
That does not say which venous problem is responsible. The review lists three: venous sinus stenosis, dural arteriovenous fistulas, and sigmoid sinus wall abnormalities, which can occur alongside a stenosis. High-grade fistulas can bleed into the brain, the review notes, which is why they are looked for specifically.
How common it is behind pulsatile tinnitus
A 2026 consensus statement from the ARISE II meeting, a roundtable of academic, government and industry experts, calls venous sinus stenosis the most common cause of pulsatile tinnitus. That is expert judgement rather than a measured prevalence, but controlled data point the same way.
A 2026 case-control study in AJNR compared 148 people with pulsatile tinnitus with 98 controls scanned for other reasons. Transverse sinus stenosis was significantly more common with pulsatile tinnitus (p < .01). Narrowing of the internal jugular vein lower in the neck was not: its prevalence did not differ between the groups.
In the 2026 Otology & Neurotology meta-analysis of stenting for pulsatile tinnitus, venous sinus stenosis accounted for 90.3% of the conditions treated.
The link with idiopathic intracranial hypertension
Idiopathic intracranial hypertension (IIH) is raised pressure in the fluid around the brain with no identifiable cause. Its link with sinus narrowing is strong and was measured early.
In a 2003 study in Neurology, 29 people with established IIH and 59 controls had contrast-enhanced MR venography, graded blind by three readers. Substantial narrowing of both transverse sinuses appeared in 27 of the 29 people with IIH and in 4 of the 59 controls. The authors reported that the grading identified IIH with a sensitivity and specificity of 93%.
Which comes first is less settled. Catheter measurements published in 1995 found high pressure upstream in the sinuses of nine people with IIH, dropping sharply at the outer third of the transverse sinus. In 2002 the same team removed 20 to 25 mL of spinal fluid during the measurement, and the venous pressure fell back immediately. They concluded that raised pressure around the brain was squeezing the sinuses, not the reverse.
The ARISE II consensus says growing evidence connects stenosis with reduced reabsorption of spinal fluid and raised pressure in a substantial subset of people with IIH, so the two may feed each other. The Frontiers review separates intrinsic stenoses, linked to arachnoid granulations inside the sinus, from extrinsic ones caused by pressure from outside, which may respond differently to treatment.
For the tinnitus specifically:
- In a 2024 meta-analysis of 694 people with IIH treated by stenting, 58.3% had tinnitus beforehand.
- In a 2021 CT study, transverse sinus stenosis did not separate IIH patients with one-sided pulsatile tinnitus from those without it. Sigmoid sinus wall dehiscence and a dominant draining side did.
- In a 2025 chart review of 132 people whose optic disc swelling from IIH had resolved, 97 (73%) had presented with pulsatile tinnitus, and 59 of those 97 (61%) still had it. Settling the eyes did not always settle the sound.
- In a 2026 registry study, 33 of 517 people stented for IIH had normal pressure in the superior sagittal sinus, upstream of the narrowing, yet their tinnitus improved at a similar rate (78.3%, against 84.6% in matched patients with high pressure).
How it is found: MR venography, CT venography and catheter venography
The Frontiers review recommends going step by step:
- MRI with MR venography is the preferred first test. It shows the venous sinuses, can show a fistula and signs of raised pressure, and involves no radiation.
- CT venography and a fine-slice CT of the temporal bone add detail about the bone and the vein, which helps with sigmoid sinus wall abnormalities and with measuring how tight a narrowing is.
- Catheter angiography remains the gold standard when a fistula is suspected or the scans are inconclusive.
- Catheter venography with manometry is the reference test when stenting is being considered. A thin catheter measures the pressure on each side of the narrowing. The review says thresholds of 8–10 mm Hg are commonly used to call a gradient significant, while noting that some patients with lower gradients have also benefited.
The pressure measurement matters because a narrowing on a scan is not proof. The 2003 study found substantial narrowing in 4 of 59 people without IIH. A 2015 review in the Journal of Neuro-Ophthalmology says imaging signs such as transverse sinus stenosis are not diagnostic of IIH, and that finding them by chance should not prompt invasive procedures unless other signs, such as optic disc swelling, are present.
The size of the gradient may also predict the result. A 2019 systematic review of 186 patients found that 81 of 86 (94.2%) with a gradient above 21 mm Hg had a favourable outcome after stenting, against 82 of 100 (82.0%) with a gradient of 21 or less.
An eye examination belongs in the same workup, because swollen optic discs are what point to IIH. Whether you need a scan covers imaging criteria for tinnitus in general, and the diagnosis guide sets out what an assessment usually includes.
What venous sinus stenting is
Venous sinus stenting is an endovascular procedure: a mesh tube is guided through the blood vessels to the narrowed sinus and opened across it, holding it wide. Antiplatelet drugs, which reduce clotting, are taken for a period afterwards. A 2024 review in World Neurosurgery says there is not yet enough evidence to standardise that medication or the other decisions after the procedure.
A 2026 meta-analysis of 40 studies and 995 patients found no significant difference in outcomes between braided and laser-cut stent designs. The River stent, the first designed for the venous sinuses, was tested in a single-arm US trial of 39 people with IIH who had failed medical treatment.
What stenting achieves for the tinnitus
The best summary is the 2026 Otology & Neurotology meta-analysis, which pooled 32 studies and 850 patients: 641 with IIH and 209 with pulsatile tinnitus alone.
- Pulsatile tinnitus improved in 89.8%.
- It resolved completely in 87.1%.
- Recurrence at last follow-up: 10.9%.
Results did not differ significantly between the IIH and tinnitus-only groups. Recurrence was higher in IIH, 12.0% against 5.7%, but not significantly.
Two other pooled analyses come out close to that. A 2024 analysis of 28 studies and 616 patients found improvement in 91.7%, complete resolution in 88.6% and recurrence in 6.5%. It did find a significant difference in recurrence: 10.6% in IIH against 2.0% when tinnitus was the main reason for stenting. The 2026 analysis of 995 patients reported complete resolution in 91.6%.
Figures this high are rare in tinnitus, and possible because the sound has a physical source, which puts venous sinus stenosis on the short list of causes that can be cured.
Complications, and the chance it narrows again
Serious complications are uncommon but real:
- A 2019 meta-analysis of 474 patients with IIH found major complications in 1.9%.
- A 2024 meta-analysis of 36 studies and 1,066 patients reported complications in 5.35%, including subdural haemorrhage (bleeding under the lining of the brain), clot forming in the stent, and urinary infection.
- The 2026 meta-analysis of 995 pulsatile tinnitus patients put the overall complication rate at 3.6%.
- In the River trial, the one serious adverse event was bleeding from the gut two months after the procedure, in a patient still taking two antiplatelet drugs.
The longer-term issue is renarrowing. A 2018 meta-analysis of 395 patients followed for a mean of 18.9 months found stent survival of 84%, with new narrowing next to the stent in 14%. A 2024 meta-analysis of 694 IIH patients put restenosis at 17.7%. The options then include a further stent or a shunt to drain spinal fluid, though the World Neurosurgery review says clearer criteria for retreatment are needed.
How strong the evidence is
Every outcome figure above comes from non-randomised studies of selected patients. The Frontiers review says questions remain about long-term durability, and that the role of stenting for pulsatile tinnitus without the classic features of IIH is still under investigation.
No randomised trial has reported. The protocol for the UK's IIH Intervention trial, published in 2026, states that there are no randomised data supporting any interventional approach for preserving vision in sight-threatening IIH. That trial randomises people at risk of losing vision to a spinal fluid shunt or to stenting, and its main outcome is swelling at the back of the eye, not the tinnitus.
Two more points are worth weighing. Several authors of the 2026 meta-analysis report consulting fees or equity from device companies, and the ARISE II roundtable included industry experts. That does not make the results wrong, but it is why independent trials matter. And the World Neurosurgery review notes there is no widespread agreement on who should be offered stenting: a pressure gradient and failed medical treatment are common criteria, but not every team requires the second.
For IIH itself, a 2025 review in Continuum notes that no drug is licensed, that acetazolamide is the most commonly prescribed, and that a GLP-1 drug lowered intracranial pressure in a phase II trial (GLP-1 drugs and tinnitus covers what that means for the sound). It also records rising use of stenting among patients who need surgery.
When pulsatile tinnitus needs urgent care
A narrowed venous sinus is not an emergency in itself, and pulsatile tinnitus on its own should be seen by a doctor within a few weeks.
Call your local emergency number or go to an emergency department if a pulsing sound comes with:
- a sudden, severe headache
- sudden neck pain
- a drooping eyelid, loss of vision or new double vision
- sudden weakness or drooping in the face or an arm, or trouble speaking or seeing
Not every pulsing sound comes from a vein. A tear in a neck artery, cervical artery dissection, can cause one: in a European study of 778 people with a dissection, 63 reported pulsatile tinnitus, and 41.3% of those 63 arrived with an ischaemic stroke, fewer than among the dissection patients without it (63.9%), so the study linked the pulsing sound to a milder course. A bulging artery in the brain has its own entry on intracranial aneurysm and pulsatile tinnitus, and a clot in the venous sinuses themselves, which can raise pressure inside the head and cause bleeding into the brain, is covered under cerebral venous sinus thrombosis.
If headaches, or vision that briefly greys out or blurs, have been building up alongside the whoosh, book sooner and say so. The Frontiers review lists headache, brief dimming of vision and pulsatile tinnitus among the typical symptoms of IIH, and the IIH Intervention protocol notes that its swollen optic discs put sight at risk. The when to seek care tool walks through these signs one at a time.
Questions to ask if stenting is suggested
- Has an eye examination checked for swelling of the optic discs?
- Was the pressure gradient across the narrowing measured, and what was it?
- Have a fistula and a sigmoid sinus wall abnormality been looked for and ruled out?
- Is the narrowing on the same side as the sound?
- Which antiplatelet medicines will I take afterwards, and for how long?
- What happens if the vein narrows again beside the stent?