Active Transcutaneous Bone Conduction Implant: Audiometric Outcomes Following a Novel Middle Fossa Approach With Self-Drilling Screws

Objective To present surgical and audiometric outcomes of patients implanted with an active transcutaneous bone conduction implant following the novel middle fossa surgical approach with self-drilling screws. Study design Retrospective review. Setting Tertiary care center. Patients Thirty-seven adults with either conductive or mixed hearing loss that met indications for an active transcutaneous bone conduction implant were consecutively implanted from April, 2013 to May, 2018. Intervention Unilateral middle fossa implantation of an active transcutaneous bone conduction implant. Main outcome measures Patient charts were reviewed for surgical outcomes and complications over the 6-year period. Preoperative air conduction, preoperative bone conduction, and 3-month postoperative aided thresholds were recorded. Speech perception was assessed using CNC words and AzBio sentences. Pure-tone averages (PTAs; measured at 0.5, 1.0, 2.0 and 3.0 kHz), air-bone gap, and functional gain were calculated. Results Mean air conduction and bone conduction PTAs (±standard deviation) of the implanted ear were 66.8 dB (±14.9 dB) and 21.9 dB (±14.0 dB), respectively. Mean aided PTA was 26.5 dB (± 8.5 dB). The average functional gain was 40.3 dB (±19.0 dB). Favorable speech perception outcomes were observed. No complications or instances of revision surgery were reported, with a mean follow-up time of 32 months (range, 9-71 mo). Conclusions This is the first paper to describe outcomes of patients implanted with an active transcutaneous bone conduction implant via the middle fossa with self-drilling screws. Favorable surgical outcomes were observed with a follow-up of up to 6 years.