Audiology – hearing test

Signs of hearing loss

Hearing loss usually develops slowly, and those around you often notice it before you do. Asking people to repeat themselves, turning up the television, losing the thread of a conversation in a noisy restaurant, feeling that everyone mumbles — these are the first signs. Tinnitus, a blocked-ear sensation or dizziness may accompany them.

In children the clues are different: delayed speech, inattention at school, television turned up too loud, repeated ear infections. Any doubt about a child’s hearing warrants an assessment, whatever their age.

What a hearing test involves

Pure-tone audiometry measures the softest sound you can perceive at each frequency, and speech audiometry assesses your ability to understand words. Both are carried out in a soundproof booth with headphones and involve no discomfort. Tympanometry completes the assessment by measuring eardrum mobility and the pressure behind it — this is the test that reveals the fluid of a middle-ear effusion. Depending on age and cooperation, other methods are available, including otoacoustic emissions and auditory brainstem responses, which require no voluntary response at all.

Reading the results

The audiogram distinguishes three broad types of hearing loss. Conductive loss arises in the outer or middle ear — earwax, a perforated eardrum, middle-ear fluid, otosclerosis — and can often be corrected medically or surgically. Sensorineural loss arises in the inner ear or auditory nerve and is managed mainly with hearing aids. Mixed loss combines the two. The degree, from mild to profound, guides what follows.

One situation that cannot wait

Sudden hearing loss, occurring over a few hours or overnight, in one ear, is a medical emergency. Treatment is far more effective when started quickly: seek care without delay.