A cochlear implant is an electronic medical device which is implanted surgically in the inner ear. Cochlear implant makes the sounds louder compared to hearing aids. The damaged hair cells of the inner ear (cochlea) is bypassed by cochlear implants which provides sound signals to the brain. Cochlear implant has been designed especially to help severely to profoundly deaf adults and children who get little or no benefit from hearing aids. Even individuals with severe or profound "nerve deafness" may be able to benefit from cochlear implants.

Cochlear implantation is indicated in the individuals where there is damage to tiny hair cells in a part of your inner ear called the cochlea. The hair cells usually identify the vibrations of sounds and send them to the brain through the auditory nerve. If it is damaged, then the sound can't reach that nerve. The implant helps in bypassing the damaged area and sends impulses to your auditory nerve directly.

The quality of sound which can be heard after cochlear implant is different from the natural hearing but the hearing is sufficient for the patient in understanding the speech. The patient cope ups well with the environment and surrounding sounds and also understands the speech well. The implants used are all approved by the Federal Drug Administration (FDA)

1. Conductive hearing loss as the name suggests occurs if there is a problem in sound waves conduction enrouting through the outer ear, tympanic membrane (eardrum), or middle ear. It may also happen if there is something that blocks the sound waves from reaching into the inner ear. The causes for such obstruction can be infections, holes in the eardrum, fluid or wax build-up behind the eardrum, or malfunction which is caused due to an infection in the part of the ear or a sudden or extreme change in air pressure and head injury. All these causative factors can lead to partial or conductive hearing loss. In such cases the treatment of choice is often surgical or medical intervention or sometimes this can even be corrected by hearing aids

2. Sensorineural hearing loss occurs if there is damage to the inner ear or the nerve from the ear to the brain which passes the messages from inner brain to brain. This type of case has more likely to have permanent hearing loss and more common than the conductive hearing loss. The main contributing factors for Sensorineural hearing loss includes prolonged exposure to loud noise or due to ageing. In children the hearing loss is due to the congenital abnormalities or infections. Furthermore, injuries to skull or skull fracture, brain injury and Genetic disorders can also lead to sensorineural hearing loss.

• Treatment for Conductive hearing loss: The treatment suggested for conductive hearing loss is -
  • Medical Management The drug or form of medicine which can be used to cure the infection or the diagnosis.
  • Surgical Intervention which includes Canalplasty, Stapedectomy, Tympanoplasty and with or without ossicular reconstruction (Depending upon the diagnosis).
  • Bone Anchored Hearing Aid (BAHA) is suggested if patient is profound to nearly normal hearing on one side or complete hearing loss in one ear. This procedure fitting consists of six stages like Investigations, treatment planning, selection, verification, orientation, and validation. The implant which is used in this procedure is Titanium Implant this is placed in the bone behind the ear. Later after a couple of months an external device is hooked up to the Titanium Implant which is similar to a hearing aid.

• Treatment for Sensorineural hearing loss : The only promising treatment available for this type is Cochlear Implant. When hearing is so poor that hearing aids provide minimal or no benefit, a cochlear implant may be considered. Over 80,000 people worldwide benefited with cochlear implants and half of all cochlear implant recipients are children’s. This device functions to stimulate the auditory nerve by passing through the injured inner ear. Patients with severe Sensorineural hearing loss still have a functional auditory nerve and the sensation of the sound is re- created by the implant.
  A wide range of sound information and performance is expected from this device. With the best appropriate rehabilitation and the duration of time, patient experience clear understanding and more speech compared to the use of hearing aids.

• Investigations/Evaluation : Patient undergoes relevant investigations which includes MRI, CT scan, X ray studies and a thorough evaluation by the team of audiologist.

• Consultation and Physical Assessment : Once the patient is identified for cochlear implant the procedure begins. The patient has a consultation with the ENT surgeons for confirming his or her candidacy based on the results of initial evaluation and investigation.

• Pre-anaesthesia evaluation and Surgery : The trial of anaesthesia is done. The procedure is performed under general anaesthesia through an incision behind the ear. The whole procedure takes nearly 2-3 hours for the completion. Post discharge the recovery is in few days and follow ups and recuperation will be advised. Post- surgery you may see a swelling behind the ear which is normal and it may take some time to subside.

• Speech processor : This is hooked up to the stimulator or the receiver after four weeks of surgery.

• Rehabilitation : The patient is then advised to undergo intensive rehabilitation under implant audiologist to cope up with the listening of sounds through the device.