Publisher's Synopsis
Hearing loss can occur for various reasons, whether it is of a genetic, congenital or acquired character. Infectious diseases stand out among those causing this type of deficiency and account for approximately 25% of all cases of profound hearing loss. Of these, one-fifth are due to congenital causes. As to classifying hearing loss, this can be done according to where this is in the hearing system, to whether the loss is unilateral or bilateral, and to its intensity or degree. Regarding where the hearing system is affected, hearing loss can be about transmission (or conduction), perception (sensorineural), or mixed. Hearing losses arising from any affection of the outer and middle ear are called transmission or conductive losses. Sensorineural losses occur due to lesions on the hair cells of the cochlear organ of Corti (inner ear) and/or of the cochlear nerve. When there is concomitant conductive and sensorineural affection, the loss is classified as mixed. Hearing loss can interfere in the lives of affected individuals, since besides affecting communication, it can influence the quality of life, when the loss leads to feelings of sadness and anxiety, or even to social isolation. In children, it can moreover represent consequences for development. Thus, appropriate treatment and/or monitoring of infectious diseases is important, the purpose of which is to see to it that hearing loss is prevented or diagnosed early.
