Unexplained Variation in Benefit of Treatment of Congenital Unilateral Aural Atresia: A Review of the Literature.

Objective A review of published data regarding binaural hearing after treatment of congenital unilateral conductive hearing loss (UCHL) due to aural atresia. Treatment options concern atresia surgery (reconstructive surgery), application of a bone conduction device (BCD), or application of a middle ear implant (MEI). Data sources Database PubMed was searched for articles published in English and German between January 1, 1994, and January 1, 2019. Study selection The initial search identified 52 studies, of which 9 met the inclusion criteria. Data synthesis Comparison of studies was based on a structured review. Meta-analysis was not feasible because of the heterogeneity of outcome measures, the limited number of relevant papers (9), and diverse types of treatment (5). Conclusions Treatment of UCHL results in bilateral hearing instead of binaural hearing. The large intersubject variability in benefit of treatment is unexplained with a clear improvement in the minority of listeners and a limited improvement or binaural interference in most listeners after atresia repair or amplification with a BCD or MEI.