Cochlear implants in children.

Abstract

In recent years, notable progress has been made in the rehabilitation of children with mild to moderate-severe hearing impairment using new and advanced hearing aids. The major problem which remained was the lack of availability of treatment options for those with severe-to-profound sensorineural hearing loss who received little or no benefit from conventional amplification. The purpose of the cochlear implant is to provide these children with direct electrical stimulation of the auditory nerve. A hearing aid amplifies incoming stimuli while a cochlear implant attempts to replace a function lost by the cochlea. In a normal hearing ear, the hair cells within the cochlea act as a transducer of mechanical energy of sound vibration to energy capable of enervating the eighth nerve. The consequence of a decrease in the number of hair cells is the loss of ability of the cochlea to perform the functions, which result in eighth nerve stimulation. The implant replaces the task of the lost hair cells by converting mechanical energy into the electrical energy necessary to excite the remaining cochlear neurons. In order to truly appreciate the application and unfolding of cochlear implants as applied to the pediatric population, it is important to summarize the development of the devices in general.