Transient disappearance of otoacoustic emissions after conventional hearing aid use in OTOF-related auditory neuropathy

OBJECTIVE: Auditory neuropathy spectrum disorder (ANSD) associated with OTOF mutations is typically characterised by prelingual hearing loss (HL), absent auditory brainstem responses (ABRs), and preserved otoacoustic emissions (OAEs). However, the long-term stability of OAEs and mechanisms underlying their decline remain poorly understood. Hearing aid (HA) use may influence outer hair cell (OHC) function and OAE responses. DESIGN: We report longitudinal audiological findings in two children with genetically confirmed OTOF-related HL. Hearing thresholds, ABRs, HA fitting parameters, and OAE evolution were analysed. A literature review assessed longitudinal OAE outcomes in OTOF-related ANSD. STUDY SAMPLE: Two children with biallelic OTOF mutations and profound HL. RESULTS: OAEs disappeared 6-12 weeks after HA fitting in both cases. Following HA discontinuation, OAEs re-emerged within 4-6 weeks, with incomplete recovery in one patient. Previous studies similarly describe progressive OAE decline in some children with OTOF-related ANSD. CONCLUSIONS: The reversible OAE loss observed after amplification raises concerns regarding possible cochlear overstimulation. These findings highlight the need for cautious HA strategies and close monitoring. Preserving cochlear integrity is especially relevant in view of emerging gene-based therapies that may require functional inner and outer ear structures. In selected cases, delaying or adapting amplification could be considered.