Clinical aspects of unilateral hearing loss

Abstract

There has been a phenomenal increase in the number of children with unilateral hearing loss (ULHL) detected by early newborn hearing screening. However, the prevalence of ULHL remains unknown. Inner ear and/or internal canal abnormalities, mumps hearing loss and congenital cytomegalovirus (CMV) infection have been identified as the major causes, while meningitis, auditory neuropathy spectrum disorder and endolymphatic hydrops are also considered as among the etiologies of ULHL. However, the etiology was indeterminate in more than half of the children with ULHL. MRI and CT studies of the inner ear should be performed for all children with ULHL. CMV DNA from the dried umbilical cord was detected in 9.1% of children with ULHL. No deafness gene mutations could be identified. Children with ULHL should be estimated by objective examinations, such as ABR, ASSR, OAE, et al., because they are sometimes diagnosed as having psychogenic hearing loss.
Children with ULHL may also show a delay of speech development, learning problems, and psychological problems interfering with personal relationships, therefore, it is necessary to provide support to them. The results of HHIA and SF-36 tests have suggested that adult patients with unilateral sudden profound sensorineural hearing loss experience hearing handicap and deterioration of the QOL in terms of daily living, recently, the Born-Anchored Hearing Aid (BAHA) has been applied as a treatment for patients with unilateral deafness hearing loss, and cochlear implantation has also been used in some patients with unilateral deafness hearing loss and tinnitus.