Severe to profound hearing loss and cochlear implants

Hearing impairment is defined by the quietest level of sounds you can hear; it is known as your hearing threshold and is measured in decibels (dBHL). Measured levels are plotted on an audiogram; an audiogram is what we plot your responses on when doing a hearing test.

These hearing thresholds are used to categorise your hearing as normal (no impairment), mild, moderate, severe or profound impairment. A severe hearing loss is traditionally classed as threshold levels of 71-95 dBHL, a profound hearing loss is threshold levels in excess of 95 dBHL.

Although useful, this description of hearing loss does not describe its pattern and shape or what type of hearing loss the audiogram displays.

As a general guide to sound levels, the following can be used:

• 70dB is the average volume of a vacuum cleaner at a distance of 1 metre
• 90dB is the average volume of a jackhammer at a distance of 15 metres
• 100dB is the average volume of a disco speaker at a distance of 1 metre

There is an estimated 87 million people worldwide with severe and profound hearing loss. Patients with severe/profound hearing loss will be unable to hear the majority of sounds unless they are very loud. Despite using hearing aids, additional support strategies including lip-reading or sign language may be required to support communication.

Patients with these levels of hearing impairments may benefit from additional accessories to work in conjunction with their hearing aid/s; speak to your audiologist for more details about these.

Where hearing aids provide only limited benefit, a cochlear implant may be appropriate.

Cochlear implants

A cochlear implant is a hearing device which works differently to a hearing aid. A hearing aid works by amplifying sounds, where as a cochlear implant works by changing sounds into electric pulses which are then sent directly to the nerves in the inner ear.

The implant is inserted into the cochlea during a surgical procedure, but prior to this there are a series of investigations and assessments to ensure that potential candidates are suitable for implantation. Following the operation each patient will undertake structured training and follow-up. The assessment/surgery is not carried out in Rotherham, you can choose where you would like to go for the assessment etc - please ask your audiologist.

Should you accept the offer of a referral to an implant centre, this does not mean that you will defiantly be having a surgery. The referral gives you the opportunist to see the specialist’s, go through the assessment process and ask any questions that you have that your audiologist may not be able to answer.

Cochlear implantation is only appropriate for a small proportion of patients with sensorineural hearing impairment. You can be referred for an assessment if your hearing threshold is 80dB or above at 2 or more of the following frequencies: 500Hz, 1,2,3,4kHz without hearing aids in place.

The potential benefits of cochlear implantation are an improvement in the ability to hear sounds (speech and environmental), speech recognition and tinnitus. Although it is a relatively simple procedure there is a small chance, as with any surgical procedure, of complications. There is good evidence that cochlear implants are effective in improving hearing in both adults and children who are unable to benefit from hearing aids. For more information please contact the audiology department.

How to contact us

Rotherham Ear Care and Audiology Department
Rotherham Community Health Centre
Greasbrough Road
Rotherham
S60 1RY

Telephone: 01709 423145 or 01709 423207
Email: rgh-tr.earcarecentre@nhs.net

Produced by Miss Kirsty Bellamy. 
Date Produced: September 2012. 
Revised December 2020, June 2021. 
Revision Due: June 2023. Version: 3.0
©The Rotherham NHS Foundation Trust 2021. All rights reserved.