What’s New Versus Tried and True in Pulsatile Tinnitus

Obesity may be the engine driving idiopathic intracranial hypertension (IIH), pulsatile tinnitus (PT), and related otologic disorders, with new research pointing to glucagon-like peptide-1 (GLP-1) receptor agonists as a way to tamp the brakes on these challenging otologic conditions. But as clinicians wait for more data on GLP-1s, the first key management step is to make an accurate diagnosis that properly guides current, more established treatment choices.

Meeting that management challenge was the focus of a panel on PT at the 2026 Triological Society Combined Sections Meeting, in Orlando, Fla.

Break Points in Tinnitus

“There are many, many causes of pulsatile tinnitus [PT],” said Bradley W. Kesser, MD, a professor of otolaryngology–head and neck surgery at the University of Virginia School of Medicine and director of the division of otology and neurotology, department of otolaryngology, at UVA Health, both in Charlottesville. “As otolaryngologists, we really have to be on our game to sort out what’s going on in these patients.”

As a guide for that detective work, “I look for what I like to call break points in tinnitus,” Dr. Kesser said. The best way to start identifying those break points, he noted, is to determine the nature of the sound and rhythm of the tinnitus, first by asking the patient, “What does your tinnitus sound like?”

If the patient describes a rhythmic, repetitive tinnitus, then it’s likely indeed pulsatile, versus the more constant, non-rhythmic tonal form that accounts for up to 95% of tinnitus cases, Dr. Kesser noted (Dtsch Arztebl Int. doi:10.3238/arztebl.2013.0451). “Then I ask them some follow-up questions, such as what the tinnitus sounds like. Is it whooshing? Clicking? A tone that varies in intensity? Is it pulse-synchronous, i.e., coincident with their heartbeat?”

The answer, he added, contains clues as to whether their PT is vascular in nature, and if so, whether the cause is likely either venous or arterial. That determination often can be done by gently compressing the patient’s neck or having them turn their head to one side. If the tinnitus resolves after these maneuvers, “then it’s likely venous,” Dr. Kesser said. If it does not resolve, and other key findings are present, such as “bounding,” which denotes a high-intensity, forceful, and exaggerated pulse sensation that is synchronous with the heartbeat, then it’s likely arterial.”

Another key break point “is whether I can hear the tinnitus through the ear canal when performing a simple auscultation,” he said. “If I can, that may indicate a venous hum due to structural abnormalities such as sigmoid sinus dehiscence [SSD] or diverticulum, which needs further imaging and workup.”

An otoscopic exam of the ear canal can also potentially yield the diagnosis. Fluid in the middle ear, or a benign tumor such as a paraganglioma, for example, can cause pulsatile tinnitus (Medicina. doi:10.3390/medicina60060914) and require imaging studies, Dr. Kesser noted.

As for which imaging study is best, Dr. Kesser said his first choice—and one supported by the literature—is computed tomography (CT) temporal bone/CT angiography imaging. The CT scan, he noted, is better suited for diagnosing SSD and other structural abnormalities than other imaging studies, such as MRIs. He pointed, as an example, to a study by Shweel et al., comparing MRI and CT, which found that MRI had an error rate of up to 15% in diagnosing PT. In fact, the tests missed two PT patients in the study who were subsequently diagnosed with internal carotid artery aneurysms, which can be life-threatening if they rupture (Am J Otolaryngol. doi: 10.1016/j.amjoto.2013.08.001).

Once you’ve successfully treated a patient who has been suffering from the debilitating effects of PT for years, be prepared for the profound response that follows, Dr. Kessler noted. “A recent patient underwent a mastoidectomy, where we identified and exposed the area of sigmoid sinus dehiscence that was contributing to her PT, and we put hydroxyapatite bone cement over that dehiscence to essentially reconstruct the bone that covers the sigmoid sinus.

“I went by to see her after surgery in the recovery room,” he said. “She was in tears. Waking up and not hearing that constant sound in her ears was a revelation.”

IIH: An Unfolding Story Across Multiple Specialties

David J. Eisenman, MD, a professor in the department of otorhinolaryngology–head and neck surgery and neurosurgery at the University of Maryland School of Medicine in Baltimore, focused his Triological Society Combined Sections Meeting presentation on the connection between PT and IIH. Awareness of this connection has unfolded among several different camps in medicine, he noted, with many insights gleaned from radiologic findings.

“We’ve long known, based on imaging studies, that people with IIH often have narrowing of the transverse sinuses,” Dr. Eisenman said. Those imaging studies show that when the transverse sinuses are narrowed, “blood drainage is impaired, which contributes to increased intracranial pressure [ICP], leading to IIH.” When neurointerventionalists treated that increased pressure by placing stents in the transverse sinus to decrease ICP, “lo and behold, they started to see that many of these patients’ PT sounds, which they had been experiencing for years, suddenly resolved,” Dr. Eisenman said.

While that was occurring in the neurosurgery and neuroradiology world, “in the ENT world, we started noticing a different finding,” he said. “We saw that many of our patients with PT had a diverticulum or were missing bone over the sigmoid sinus, which is just downstream from the transverse sinuses.” Because CT scans have shown that this sigmoid sinus dehiscence can cause PT, “we started doing operations to reconstruct the sigmoid sinus or reduce the diverticulum. And we found that those surgeries often also resolved the patients’ pulsatile tinnitus.” The next key insight occurred “when the neurointerventionalists eventually reported that their patients with transverse sinus stenosis also had sigmoid sinus wall anomalies, and at the same time we realized that our patients with sigmoid sinus wall anomalies had transverse sinus stenosis,” Dr. Eisenman said.

The lesson? “These patients are not experiencing three separate things—IIH, transverse sinus stenosis, or sigmoid sinus wall anomalies,” Dr. Eisenman said. “They are three different sides of the same story.” Specifically, “transverse sinus stenosis creates turbulent blood flow—that’s the noise production component,” he said. “But then you need noise access, and that’s provided by the loss of bone over the sigmoid sinus; it’s like opening a window and letting the sound in. Both of them are necessary, and in most cases, neither one is sufficient. If you treat either one—by stenting to resolve the stenosis, or sigmoid sinus reconstruction to repair the ‘window’—their PT gets better.”

As for which approach is best, two-year safety and efficacy data on stenting in IIH patients are solid (World Neurosurg. doi:10.1016/j.wneu.2018.09.070), Dr. Eisenman noted. “But what about five or 10 years out? How about stent migration through the wall of the vein?” The latter, he noted, poses a risk because the stents used in these procedures were originally designed for arteries, which are much stronger than the placement sites in the transverse sinus. “Plus, you have to be on blood thinners for the rest of your life to prevent stent-related clotting, which carries its own risks,” he said.

With sinus wall repair, in contrast, “we’ve got strong data that show good durability of our surgical approach, with very few complications.”

That study data, Dr. Eisenman noted, was part of his Triological Society thesis (Laryngoscope. doi:10.1002/lary.27218). In the thesis study, treatment responses were evaluated in 40 ears among 38 patients with sinus wall anomalies who underwent transtemporal sinus wall reconstruction. Of those, 23 ears had SSD, and 17 had diverticulum. A total of 36 out of the 40 subjects (90%) had complete resolution of their PT following surgery, including all of those with diverticulum. A follow-up study on 37 of 58 eligible patients showed good long-term durability of the success over a median follow-up of close to 10 years (Otol Neurotol. doi:10.1097/MAO.0000000000004352).

Dr. Eisenman’s Triological Society thesis also includes several surgical tips for sigmoid sinus surgery, including avoiding the “minimalist” approach some surgeons take with these patients. “I prefer instead to do a bit more work to lessen the risks of the sinus wall anomaly recurring over the long term. If there is an outpouching, for example, I like to shrink that down and cover the area with soft tissue and layers of bone.” He stressed, however, that this approach is based primarily on practice experience, rather than long-term published outcomes data.

Another Vote for CT Scans—with a Twist

No surgery will be a success without a proper imaging-based diagnosis, Dr. Eisenman stressed. He echoed Dr. Kesser’s vote for CT scans—but with an important twist. “You need to choose an imaging study that will let you look both at what’s making the tinnitus noise and at what’s letting you hear the noise. An MRI, by itself, is not sufficient, nor is a non-contrast CT scan. Rather, you need a modified form of a CT scan that looks at contrast in the veins and in the arteries and lets you see the fine anatomy of the temporal bone to look for superior canal dehiscence, otosclerosis, and carotid dehiscence.”

The efficacy of that approach is underscored in Dr. Eisenman’s own research, which showed that a bone-windowed CT angiogram had an efficacy rate of 96.5% in detecting transverse sinus stenosis and other structural abnormalities related to PT (Otol Neurotol. doi:10.1097/MAO.0000000000004745).

As a final diagnostic tip, Dr. Eisenman noted that women in their 30s or 40s who are markedly overweight are susceptible to developing IIH, particularly those with a history of headaches and visual disturbances (Laryngoscope. doi:10.1002/lary.32389). “What we now realize is that many of these patients also have PT,” he said. Indeed, one 38-site prospective study of 152 IIH patients found that 52% of the patients had pulse-synchronous tinnitus (JAMA Neurol. doi:10.1001/jamaneurol.2014.133). “Unfortunately, many of these patients are still seen by only an otolaryngologist or a neurotologist,” he said. That siloed approach “misses the key point that IIH and PT are very inter-related conditions that need a multidisciplinary approach to ensure an optimal diagnosis and treatment outcome.”

It Takes a Team to Tackle PT

Tiffany Hwa, MD, an assistant professor in the division of otology and neurotology, department of otolaryngology–head and neck surgery at the University of Pennsylvania Health System, in Philadelphia, echoed the dangers of being siloed when caring for patients with PT.

“It’s particularly important to take a multidisciplinary approach because PT crosses so many anatomical boundaries,” said Dr. Hwa, who was not part of the Triological panel but co-authored a Bulletin on the evaluation and management of PT for the American Academy of Otolaryngology–Head and Neck Surgery (AAO-HNS. bit.ly/4sVLU4a). At UPenn, “whether it’s neurosurgery, neurotology, neuro-ophthalmology, or neurology, we will collaborate with any or all of these specialties to ensure the best possible outcome,” she said.

Dr. Hwa is a member of the AAO-HNS Skull Base Surgery Committee. Part of the Committee’s remit, she noted, is to track educational gaps in ENT practice, and PT often came up as an area where generalist ENTs struggle. “I am a subspecialist of a subspecialty, and even I sometimes can struggle with PT management,” Dr. Hwa said. To fill some of the key awareness gaps regarding PT, the AAO-HNS PT Bulletin reviews the usual helpful tips, including how to listen for particular sounds and rhythms of PT as a clue for a vascular or non-vascular cause.

Dr. Hwa echoed the other experts’ view that a CT angiogram of the head and neck “is the best bang-for-your-buck test” for elucidating the causes of a patient’s PT. “But here’s an added tip: Ask the radiologist to sequence thin cuts. By doing so, you can get two tests out of one; it also will allow you to do a CT temporal bone scan, which captures additional underlying conditions that may be missed without the thin-cut protocol.” Those conditions could include, she explained, venous malformations such as sigmoid sinus diverticulum/dehiscence, or even rare entities such as an erosive skull base tumor (Otol Neurotol. doi:10.1097/MAO.0b013e31829ab6d7).

Dr. Hwa cited another evolving trend in PT and IIH: the increasing awareness that obesity plays a major role in the disorders. In the case of IIH, studies have shown that its incidence increases exponentially with gains in body mass, and patients who undergo bariatric surgery experience significant reductions in ICP and IIH symptoms (Neurology. doi:10.1212/WNL.0000000000200839).

Because of the huge demographic upswing in obesity, some of Dr. Hwa’s UPenn colleagues, including Adam Vesole, MD, a neurotology fellow, are studying whether glucagon-like peptide-1 receptor agonists can play a therapeutic role in PT. “This is a very exciting new development,” Dr. Hwa said. (See sidebar for an account of Dr. Vesole’s research.)    

David Bronstein is a freelance medical writer based in New Jersey.