Treating hearing loss: a primer

Hearing loss is a silent but debilitating handicap. If it strikes before language acquisition occurs- before the child is two or three tears old- an untreated child with profound loss may never speak. Children with partial hearing loss tend to lag behind their peers in class and may not rise to their scholastic potential.

Their vocabulary may be limited and pronunciation impaired. Behavioural backwardness sets in and they tend to have fewer friends and social skills may be poor. Adults with hearing loss often experience difficulty in the workplace and often don’t reach the potential that they can be capable of. They tend to shun company, avoid friends and especially avoid social gatherings and parties in clubs, pubs and restaurants because they feel most inadequate in these environs. Psychological issues are common in elderly patients with hearing loss. Typically they don’t have the drive or the incentive to seek help as compared to the working person. Helping them is a big challenge and is almost as rewarding as making a hearing impaired child socially adequate.

Hearing loss is of two major varieties: due to impaired conduction of sound from the ear drum to the nerve- conductive hearing loss- and those due to disorders in the inner ear and the nerve- sensorineural hearing loss.

Conductive hearing loss is often treatable; impacted wax in both ears may cause upto 30dB of hearing loss and relieved in jiffy! Ear drum perforations, fixity or loss of one or more of the minute bones that carry the sound from ear drum to the inner ear are often treated successfully by surgery. Some patients with conductive hearing losses may choose to wear hearing aids while others may need implants in which sound is first digitised, filtered, enhanced and then delivered as sound to the inner ear.

Sensorineural hearing loss is more difficult to treat. A majority of patients can be treated with hearing aids that are miniature sound systems- amplifier,mic and speaker all rolled into one! Needless to add there is a lot of sophistication, miniaturisation and computerisation involved in all this. When profound hearing loss is not helped even with powerful hearing aids, a cochlear implant is considered. Surgery first implants the receiver-stimulator package behind the ear and after a fortnight or so the external sound processor is worn and the implant “switched on”. The implantee needs rehabilitation and appropriate care for the first few months after surgery because the sound is first digitised by the processor and then transmitted as electrical signals directly to the organ of hearing and nerve. Especially a child needs extensive postoperative rehabilitation to recognise and reproduce speech. The results of surgery are astounding. Deaf mutes can speak, go to college and seek gainful employment in the open market. Adult implantees hardly need much rehabilitation since they have already acquired speech-are post lingual. Even in them too results are marvellous.

The key to successful rehabilitation of hearing loss is diagnosis and then tailoring the treatment to the persons age and needs.

Prabodh Karnik