Stem Cell May Be the Future Cure to Hearing Loss with Bionic Ear as Hope

Yeditepe University Kozyatağı Hospital Ear, Nose, and Throat Specialist Prof. Dr. Müzeyyen Doğan emphasized that hearing is one of the most important senses that enable people to communicate with the environment and stated that it will not be possible for a child who does not hear in the first years of life to speak because word memory cannot be formed in their brain.

Stating that the normal human ear can hear sounds between 20 Hz and 20 thousand Hz, Doğan said, "Speech frequencies are 500 Hz, 1000 Hz, 2000 Hz, and 4000 Hz. When it starts to be lost at high frequencies, a thin sound is heard, which is described as ringing in the ear in proportion to the degree of loss and can be noticed in quiet environments. Therefore, the patient does not present with a complaint of hearing loss, but with a complaint of ringing. When speech frequencies are lost, the patient's communication in daily life is affected. The journey of sound waves to the inner ear and/or the transmission of sound waves from the inner ear to the brain can be hindered for various reasons."

Stating that losses up to the inner ear are called "conduction type hearing loss", while losses from the inner ear to the brain are defined as "sensorineural hearing loss", and if the two pathways are affected together, "mixed type hearing loss" occurs, Doğan said that the obstacles that may occur in the auditory pathways in every period of life, starting from intrauterine life, lead to different degrees of hearing loss.

"Hearing Impairments Accelerate the Onset of Dementia"

Prof. Dr. Müzeyyen Doğan stated that the causes of conductive-type hearing loss are usually treatable diseases when detected in the preliminary period, and noted the following:

"Sensorineural hearing loss is hearing loss caused by the natural aging process or degeneration of the nerves that go from the inner ear to the brain. Hearing aids are used to increase the patient's hearing. In the mixed-type hearing loss, there is a problem in both transmitting the sound to the inner ear and transmitting it to the brain by converting it into electrical signals by the inner ear. We can give examples of chronic middle ear infections that have been going on for a long time and are infected. First, medical, and surgical treatments are applied to dry the infection. A hearing aid can then be worn to increase residual hearing."

Stating that the number of hearing-impaired people registered in the national data system in the July 2022 report of the Disabled Statistics Bulletin in Turkey is reported as 179 thousand 867, Doğan said, "Individuals can healthily develop psychosocial development by establishing healthy communication. We start to speak thanks to the word memory that occurs in the first 2 years of life. Children who cannot hear or express their feelings and desires begin to become aggressive. We also check hearing first in children with delayed speech and speech disorders as well as the inability to talk. "Frequent recurrent middle ear infections in childhood should be diagnosed and treated without causing permanent damage," she said. Doğan pointed out the importance of hearing for the person to socialize and said that hearing impairments occurring in middle and advanced ages gradually started to detach individuals from their social environments, these individuals started to cut off communication because they were afraid of repeating what was spoken frequently to those around them, which accelerated the onset of dementia as a result of the lack of environmental stimuli.

"Bionic Ear" Can Be Attached to Those with Advanced Sensorineural Hearing Loss

Doğan also stated that a decrease in work performance, memory weakness, and decreased attention are among the other negative effects of hearing loss and gave the following information about the new device developed for people with hearing impairment and the projects carried out:

"We have developed hearing aids that we recommend to people with sensorineural hearing loss and provide ease of use. There are hearing aids that can be placed and removed by the patient in the outer ear canal. Some devices mask environmental noise, can mask the ringing sound in the ear, and even make adjustments to the application that the person will download to their mobile phone. Patients with severe sensorineural hearing loss or who do not benefit from traditional hearing aids may be fitted with cochlear implants, commonly known as "bionic ears". It consists of two parts, one placed under the skin and the other inside the ear. The sounds in the environment are converted into electrical stimulation and the hearing cells are stimulated. It is applied in children with severe sensorineural hearing loss detected up to 4 years of age. Recently, stem cell studies are continuing to renew the hearing cells in the inner ear. In Turkey, the hearing test for newborn babies in the first 48 hours is part of the national newborn hearing screening program. Detecting children with hearing loss at a very early stage and ensuring that they can hear will also prevent them from having speech problems in the future."