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Objective: A discussion on whether recent research on noise-induced cochlear neuropathy in rodents justifies changes in current regulation of occupational noise exposure.Design: Informal literature review and commentary, relying on literature found in the authors’ files. No formal literature search was performed.Study sample: Published literature on temporary threshold shift (TTS) and cochlear pathology, in humans and experimental animals, as well as the regulations of the US Occupational Safety and Health Administration (OSHA).Results: Humans are less susceptible to TTS, and probably to cochlear neuropathy, than rodents. After correcting for inter-species audiometric differences (but not for differences in susceptibility), exposures that caused cochlear neuropathy in rodents already exceed OSHA limits. Those exposures also caused “pathological TTS” (requiring more than 24 h to recover), which does not appear to occur with human broadband noise exposure permissible under OSHA.Conclusion: It would be premature to conclude that noise exposures permissible under OSHA can cause cochlear neuropathy in humans. [ABSTRACT FROM PUBLISHER]

Objectives The auditory brainstem implant (ABI) is an option for hearing rehabilitation in profoundly deaf patients ineligible for cochlear implantation. Over the past decade, surgeons have begun implanting ABIs in pediatric patients who are unable to receive cochlear implants due to congenital or acquired malformations of the inner ear. No study has examined the potential population-level demand for ABIs in the United States (US). Herein, we aim to quantify the potential need for pediatric ABIs. Methods A systematic literature review was conducted to identify studies detailing the rates of congenital cochlear and/or cochlear nerve (CN) anomalies. Absolute indications for ABI include bilateral cochlea or CN aplasia (Group A), and relative indications for ABI include bilateral cochlea or CN hypoplasia (Group B). Data was subsequently correlated to the US Census Bureau, the National Health Interview Survey, and the Gallaudet Research Institute to provide an estimation of pediatric ABI candidates. Results Eleven studies documented rates of bilateral findings. Bilateral cochlea aplasia was identified in 0–8.7% of patients and bilateral CN aplasia in 0–4.8% of patients (Group A). Bilateral cochlea hypoplasia was identified in 0–8.7% of patients and bilateral CN hypoplasia in 0–5.4% of patients (Group B). Using population-level sensorineural hearing loss data, we roughly estimate 2.1% of potential implant candidates meet absolute indications for an ABI in the United States. Conclusion Congenital cochlear and cochlear nerve anomalies are exceedingly rare. This study provides the first preliminary estimate of cochlea and CN aplasia/hypoplasia at the population level albeit with limitations based on available data. These data suggest the need for dedicated ABI centers to focus expertise and management. [ABSTRACT FROM AUTHOR]