Introduction to Pulsatile Tinnitus

What is PT?

Pulsatile tinnitus is a rare form of tinnitus where the sound beats in time with your pulse. It is not a disease itself but a symptom that often relates to blood flow or cerebrospinal fluid (CSF) movement near the ear.

While non-pulsatile tinnitus usually arises from inner ear or hearing pathway problems, pulsatile tinnitus is more often due to awareness of blood or CSF flow. It can interfere with concentration, sleep and work, and in some people is linked with anxiety or low mood. In certain cases, it may be the first sign of an underlying medical condition.

Is it serious?

The noise itself is not usually harmful. However, the underlying cause can be important and occasionally urgent, such as a dural arteriovenous fistula or severe narrowing of the carotid artery. Medical assessment is particularly important if the tinnitus is new, worsening, or associated with neurological or visual symptoms.

What causes it?

Pulsatile tinnitus is most often caused by turbulent or altered blood flow close to the ear, though in some cases it is due to increased awareness of otherwise normal flow. Common venous causes include idiopathic intracranial hypertension (IIH) with transverse sinus stenosis (TSS), where turbulent flow transmits to the cochlea. Sigmoid sinus dehiscence or diverticulum, where a bony defect or outpouching allows venous noise to reach the ear, is another frequent cause. Abnormalities of the jugular vein, such as a high-riding jugular bulb, diverticulum or narrowing, can sometimes present with a bluish mass behind the eardrum and tinnitus. Other venous contributors include marginal sinus stenosis and enlarged emissary veins, which may be treated in selected cases.

Arteriovenous causes include dural arteriovenous fistulae, which are acquired abnormal connections and often produce loud tinnitus that can even be heard by an examiner. Carotid cavernous fistulae, often developing after trauma, may cause both pulsatile tinnitus and eye symptoms. Arteriovenous malformations are a rare cause.

Arterial conditions can also be responsible. Carotid artery narrowing from atherosclerosis becomes more common with age, high blood pressure and high cholesterol. Internal carotid dissection may present with headache, neck pain or neurological signs, with tinnitus occurring in a minority of cases. Fibromuscular dysplasia, which affects medium-sized arteries and often occurs in women, is another recognised cause. Less commonly, aneurysms of the internal carotid or vertebral arteries, as well as congenital variants such as an aberrant carotid course or persistent stapedial artery, can produce symptoms.

Systemic conditions including high blood pressure, anaemia, overactive thyroid, Paget disease, middle ear tumours and head trauma may also contribute.

Is it inherited?

Pulsatile tinnitus is usually not inherited. Although some people are born with variations in their blood vessels that predispose them to symptoms, most causes develop later in life.

Who is more at risk?

Women of childbearing age with raised body mass index and idiopathic intracranial hypertension are at particular risk. Older adults with atherosclerosis or other vascular risk factors are also more likely to be affected. People with high blood pressure, anaemia, overactive thyroid or Paget disease, and those with a history of head or neck trauma or venous sinus thrombosis, may be more susceptible.