What is tinnitus?
Tinnitus represents “an illusion of sounds in the absence of a physical stimulus”. The condition can be assessed using the tinnitus handicap inventory score, and classified as either subjective or objective.
Subjective tinnitus involves perceiving sound without an external cause, and typically associates with high-frequency hearing loss — this is the most prevalent form. Objective tinnitus involves detecting actual sounds generated by bodily processes or vibrations, often exacerbated by conductive hearing loss (dysfunction in the ear canal, eardrum, or middle ear bones).
Two theories explain how tinnitus is caused. The first suggests that during quiet moments the auditory nerve produces sporadic signals, perceived as sound by the brain. The second proposes that a failure to adapt to background noise increases stress and tinnitus prominence.
The condition affects roughly one in three people over the age of 50, with more than half experiencing daily episodes. Various causes of hearing loss can present with tinnitus, including sensorineural hearing loss and Eustachian tube dysfunction.
Treatment for vascular pathology depends on the underlying cause, though mechanical issues tend to be challenging to address. The British Tinnitus Association website (www.tinnitus.org.uk) provides coping strategies, support groups and educational resources about tinnitus management.
Patients with regular or intrusive tinnitus should consider completing the “tinnitus inventory index” before consultation, to facilitate discussion of the results.
Subjective tinnitus
While hearing loss is the most common cause of tinnitus, multiple rarer causes exist:
- Tumours on the vestibulocochlear nerve
- Meniere’s disease
- Medications
- Trauma (including excessive loud-sound exposure)
- Neurological problems
- Cardiovascular diseases
- Metabolic conditions (such as thyroid level changes)
Treatment targets the underlying cause. When no identifiable cause emerges, options include avoiding exacerbating factors, reducing stress, and tinnitus therapy. Hearing aids amplify background noise, benefiting patients with concurrent hearing loss. For persistent cases, “maskers” produce sounds at similar frequencies to the tinnitus, aiming to obscure the patient’s actual perception.