Bionic Ear Allows Regaining of Hearing Ability
Date:
01/06/2011
The sense of hearing is one of the basic functions that facilitates communication with the environment, contributes to mental, social and intellectual development. This is why whether prior to or after birth the development of hearing loss, especially in both ears has significant effects on the quality of life. The early diagnosis and treatment of hearing impediments or loss especially in babies is extremely important.
All people with hearing impediments, regardless of age has the chance of overcoming the difficulties of living with hearing loss by means of cochlear implants, more commonly known among society as the bionic ear. Sertaç Yetişer, M.D. Professor of ENT, provides more information on the opportunities the cochlear implant can provide patients with hearing impediments.
What is a cochlear implant?
The cochlear implant is an electronic device that transforms mechanical audio energy into electrical signals and transfers this information directly into the inner ear, thus allowing the perception of sound. The device is formed of two main components. First is the part that is placed under the skin behind the ear. During the operation, the lengthy electrode of this device is implanted into the inner ear, otherwise known as the cochlea. The coded electrical energy transporting the sound energy information transmitted from the external coil, in other words from the antenna to the inner ear by means of the electrode to stimulate the hearing nerve. After implantation by surgery patients keep this piece for the rest of their lives. The external part is composed of a sound processor, microphone and external antenna. The external coil is placed on the hairy part of the skin and holds on to the internal coil magnetically by means of a special magnet.
What are the advantages of the bionic ear?
Children with normal hearing ability learn to speak in their family environment without the need for special help. Patients with severe or significant hearing impediments cannot benefit from even the most powerful of hearing aids. Deaf children unable to hear others speaking will not be able to develop language and special communication skills. The cochlear implant provides such children the opportunity to differentiate the sounds in their environment, develop language skills, seek employment and manage to stand on their own feet. How can a deaf person hear with the bionic ear?
The tympanic membrane (eardrum) and the auditory ossicles in the middle ear transmit sound waves into the inner ear in the form of mechanical energy. The actual sense of hearing occurs in the inner ear, or otherwise known as the cochlea. The sound signal reaching this part of the ear is transformed into electrical signals that travel along the hearing nerve towards the hearing centre of the brain by means of very small cells. This involves the stimulation of the inner ear with artificial electrical signals. Patients with hearing nerve damage from various reasons can start to hear once more by means of the cochlear implant stimulating the hearing nerve.
How can you describe sound perceived by the bionic ear?
People with the bionic ear can hear processed and coded sounds. People with normal hearing wouldn't really know but we think that it could be described as something similar to a person speaking with a towel pressed on their mouth or in a slightly metallic tone. In the end the sounds heard are not natural, they are what the device can transmit to the person. People who receive cochlear implant at a very early age would not notice the difference in sound thanks to sophisticated technological advancements. We frequently are astonished at the linguistic abilities of certain patients with cochlear implants.
Can people start to hear immediately after the implantation of the bionic ear?
Every sound is new for people with the cochlear implant system. Learning to interpret the sounds generated from the implant requires patients to get involved in a learning process. This is what hearing training following the implantation is very important. Although cochlear implants allow hearing of sounds, this is not enough for the person to individually understand the language spoken only by listening. Hearing training is fundamental as it provides the ability to understand and differentiate the sounds heard by patients.
Early diagnosis of hearing impediment and placement of implant with such a diagnosis in the shortest possible duration will clearly increase the affectivity of the training process. Infants and adults who develop hearing impediment after learning how to speak will naturally have experience with the perception of sound. The intervals generated whilst these people perceive sound signals can be compensated by memory. This is why people who have developed hearing impediments in later stages are generally capable of passing stages of hearing and understanding more easily.
Is the cochlear implant a viable solution for all deaf people?
Several factors are taken into consideration in identifying candidates for cochlear implantation which include age, mental and physical health, audiologic assessment results, reason and duration of hearing loss, compatibility to audiologic rehabilitation, social condition etc. Prior to confirming the decision for surgery, assessments should be made to determine if the patient can be trained appropriately and the type of benefit anticipated after the operation. There are patients with hearing loss and multiple problems. Some might be mentally disabled. Such conditions must also be considered. The radiological assessment of candidates is just as important as other factors. Hence, each patient must be assessed by computerised tomography and magnetic resonance imaging techniques prior to surgery. Patients who are suitable candidates for cochlear implants are deaf born children and the middle age group who have lost their sense of hearing due to genetic, auto-immune, trauma, medication use, tumour, infection or excess noise.