Tinnitus

Introduction

Tinnitus is the perception of sound in the ears or head, where no external source of the sound exists.

Tinnitus can be divided into two main types:

Subjective

This is by far the most common type of tinnitus, where there is no acoustic stimulus.

Many doctors are concerned that their patient with tinnitus could have an acoustic neuroma (also known as a vestibular schwannoma) but in fact acoustic neuromata are rare, with an incidence of just 1 per 100,000 people per year. They also tend to present with unilateral sensorineural hearing loss, not necessarily with tinnitus. Overall, only 2% of patients with unilateral tinnitus along with sensorineural hearing loss will prove to have a vestibular schwannoma¹.

Objective

This is rare and occurs when there is actually a noise to be heard being generated within the head. These can be:

• Pulsatile: due to movement of blood - eg, carotid stenosis, vascular anomalies or tumours, valvular heart disease, high cardiac output states.

• Muscular or anatomical: palatal myoclonus, spasm of tympanic muscles, patulous Eustachian tube.

• Spontaneous: otoacoustic emissions.

Aetiology

Subjective

Common causes are:

• Otological: noise-induced and other forms of hearing loss, presbyacusis, otosclerosis, impacted cerumen, ear infection, Ménière's disease.

• Neurological: head injury, multiple sclerosis, acoustic neuroma and other similar tumours.

• Infectious: meningitis, syphilis.

• Drug-related: salicylates, non-steroidal anti-inflammatory drugs (NSAIDs), aminoglycosides, loop diuretics, cytotoxicity.

• Jaw disorders: temporomandibular joint dysfunction.

Many cases of tinnitus have no identifiable cause.

Objective

Noises generated within the head can be:

• Pulsatile: due to movement of blood - eg, carotid stenosis, vascular anomalies or tumours, valvular heart disease, high cardiac output states.

• Muscular or anatomical: palatal myoclonus, spasm of tympanic muscles, patulous Eustachian tube.

• Spontaneous: otoacoustic emissions.

Epidemiology

Tinnitus is a common complaint. NHS England's Joint Strategic Needs Assessment Guidance estimates that 10% of the adult population will have tinnitus at some point. It will be moderately annoying in 2.8% of the population, severely annoying in 1.6% and disrupting a person's ability to live a normal life in 0.5%. The prevalence in children is similar².

The presence of tinnitus has been reported to increase progressively with age, affecting 5% of people aged 20-30 years and 12% of people over 60 years of age³.

The link between depression and tinnitus has been queried in the past but a large comprehensive systematic review reported a prevalence of 33% in people who had tinnitus⁴.

The link between tinnitus and suicide is controversial. The guidance from the National Institute for Care and Health Excellence (NICE) specifically recommends referring people with tinnitus to a crisis mental health management team if they have a high risk of suicide⁵. However, a large literature review failed to draw any definitive conclusion about a link between suicide and tinnitus⁶.

Presentation

Symptoms

Patients often take a long time before seeking medical attention.

Most common sounds are:

• Ringing

• Buzzing

• Cricket-like

• Hissing

• Whistling

• Humming

The condition may be unilateral or bilateral. If bilateral, it may be equal in both sides or louder in one ear than the other⁷.

Examination and investigations⁵

• Assess the effect that tinnitus is having on the person's function, mental health, quality of life and sleep. A number of formal questionnaires and scoring systems are available. NICE guidance refers to the Tinnitus Functional Index and the tinnitus questionnaire (TQ).

• Thorough examination of the head, neck, ears and jaw should be made. Although most patients with tinnitus will have a normal clinical examination, it is important to check for:

  • Impacted earwax (which can sometimes cause tinnitus and is easily rectified).

  • Carotid bruit (in the case of pulsatile tinnitus).

  • Cranial nerve defects (which can signify a neoplasm in the brain stem or posterior nasopharynx).

  • Otitis media (although of course the patient will have ear pain too).

  • Masses or glands up in the neck, or behind the ear (which can signify a neoplasm).

• A formal hearing test is recommended. This is because hearing loss is commonly associated with tinnitus and may be the cause of it. Although patients report sound as being loud, hearing tests demonstrate that they are at an intensity that is only just louder than the softest sound audible at that frequency - usually above 3 kHz. Treating the hearing loss with a hearing aid may help to alleviate the tinnitus.

• Tympanometry should be considered if conductive hearing loss is suspected.

• Hypertension is not thought to cause tinnitus. However, slightly more people with tinnitus have hypertension than do not. This may be because of the ototoxicity of the drugs used to treat the hypertension (ACE inhibitors, diuretics, calcium-channel blockers, potassium-sparing diuretics and aspirin all have a weak association with tinnitus)⁸.

Non-pulsatile tinnitus

• MRI of the internal auditory meatus should be offered to people with non-pulsatile tinnitus who have associated neurological, otological or head and neck signs and symptoms. If MRI is contra-indicated, contrast-enhanced CT is a suitable alternative.

• Consider offering MRI of internal auditory meatus to people with unilateral or asymmetrical non-pulsatile tinnitus who have no associated neurological, audiological, otological or head and neck signs and symptoms. Contrast-enhanced CT is an alternative.

• Do not offer imaging to people with symmetrical non-pulsatile tinnitus wiho have no associated neurological, audiological, otological or head and neck signs and symptoms.

Pulsatile tinnitus

• For people with synchronous pulsatile tinnitus, consider:

  • Magnetic resonance angiogram or MRI of head, neck, temporal bone and internal auditory meatus if clinical examination and audiological assessment are normal, or contrast-enhanced CT of head, neck, temporal bone and internal auditory meatus if these modalities are contra-indicated. Consider offering contrast-enhanced CT of temporal bone if an osseous or middle-ear abnormality is suspected (for example, glomus tumour), followed by MRI if further investigation of soft tissue is required.

• For people with non-synchronous pulsatile tinnitus (for example, caused by palatal myoclonus), consider:

  • MRI of the head, or if they cannot have MRI, contrast-enhanced CT of the head.
    

Management⁵

General measures

• Tinnitus support or counselling: this is a formal description NICE uses for a consultation in which information between the patient (and if necessary their carer or family) and doctor is passed in a two-way process. It enables the doctor to understand the impact that tinnitus is having on the person's life (tinnitus-related distress) and to give them information. It is important to give the patient an explanation about the condition and reassurance that it will not progress and that there are no sinister findings. A management plan can jointly be agreed at the end of the session.

• There is a strong association between tinnitus and stress; relaxation techniques or relaxing background music can distract or mask some tinnitus.

• If tinnitus-related distress does not respond to tinnitus support, consider referral - in the following order - for:

  • Digital-related cognitive behaviour therapy (dCBT). This is a form of CBT delivered using digital technology, such as a computer, tablet or phone, and overseen by a psychologist. The actual therapy is similar to that used in face-to-face CBT (for example, positive imagery and learning to identify and challenge unhelpful thoughts).

  • Group-based cognitive therapy delivered by appropriately trained and supervised practitioners or psychologists.

  • Individual tinnitus-related CBT delivered by psychologists.

• Tinnitus-retraining therapy is no longer recommended. NICE considers that the evidence base is limited.

• Recommend amplification devices for people with tinnitus and hearing loss.

• Masking devices (termed 'sound therapy' by NICE) have traditionally been advocated, but NICE feels this treatment modality requires further research.

Pharmacological

Patients who have experienced tinnitus for a while are often desperate for a treatment to help alleviate the noise. The doctor is often equally as desperate. Several therapies have been tried in the past, including:

• Anti-vertigo drugs - eg, betahistine.

• Antidepressants.

• Anti-convulsants.

• Anxiolytics.

• Intratympanic medication.

• Ginkgo biloba.

• Melatonin.

• Zinc.

NICE has, however, been unable to find sufficient evidence to recommend any particular pharmacological therapy.

Surgical

Surgical treatment is rarely used, unless a surgically treatable underlying cause has been identified (eg, an acoustic neuroma)⁷.

When to refer

• Refer immediately to a crisis mental health management team for people who have tinnitus associated with a high risk of suicide.

• Refer immediately, people with tinnitus associated with:

  • Sudden onset of significant neurological symptoms or signs (for example, facial weakness); or

  • Acute uncontrolled vestibular symptoms (for example, vertigo); or

  • Suspected stroke.

• Refer people to be seen within 24 hours if they have tinnitus and sudden hearing loss (developed (over a period of three days or less) in the previous 30 days.

• Refer people to be seen within two weeks for assessment and management if they have tinnitus associated with either of the following:

  • Distress affecting mental well-being even after receiving tinnitus support.

  • Hearing loss that developed suddenly more than 30 days previously or rapidly worsening hearing loss (over a period of 4 to 90 days).

• Refer people for tinnitus assessment and management in line with local pathways if they have any of the following:

  • Tinnitus that bothers them despite having received tinnitus support.

  • Persistent objective tinnitus.

  • Tinnitus associated with unilateral or asymmetric hearing loss.

• Consider referring people for tinnitus assessment and management in line with local pathways if they have any of the following:

  • Persistent pulsatile tinnitus

  • Persistent unilateral tinnitus