Lifetime Real-World Evidence on Safety and Performance of the Only Active Middle Ear Implant (AMEI) Covering Conductive to Sensorineural Hearing Loss: Results From a Long-Term Retrospective Analysis

OBJECTIVE: Confirm the safety and performance of an implantable active middle ear implant in patients who have been implanted for a minimum of 5 years before 2022.

SETTING: Otolaryngology departments of 4 German and Austrian hospitals.

STUDY DESIGN: Retrospective, multicenter, longitudinal, open-label case series study.

PATIENTS: Six hundred forty-seven ears treated for conductive, mixed, or sensory neural hearing loss implanted for 5 years (622 aged 18 y or older, 23 aged 5 to 17 y, and 2 under 5 y of age) at time of implantation.

INTERVENTION: Implantation of the Vibrant Soundbridge (VSB) system, a partially implantable active middle ear implant (AMEI).

MAIN OUTCOME MEASURES: Patients' audiometric pure tone averages (PTA4) (0.5, 1, 2, 4 kHz) thresholds (bone conduction, and sound field) and speech perception [word recognition scores (WRS)] were retrospectively collected up to 24 years postoperatively. Complications were recorded with focus on revision surgery and explantations. Subgroups were vibrant ossicular prothesis models 502 and 503 as well as conductive+mixed hearing loss (C/MHL), sensory neural hearing loss (SNHL), adults and children.

RESULTS: Safety was established by stable bone conduction thresholds with a mean difference of -3.86 dB 5 years or later after implantation. Safety was further established by no technical failures reported for the VORP 503 and only 7 for the VORP 502 and high survival rates of 84.06% 10 years after implantation. For all subgroups (VORP 502, VORP 503, C/MHL, SNHL, adults and children) mean BC-PTA4 thresholds remained stable at 5 and 10 (only VORP 502) years postoperatively. Paired mean sound field PTA4 thresholds and word recognition scores are significantly improved as tested by post hoc analysis 5 years or later after implantation with functional gains of 29.87 dB (ALL), 28.64 dB (VORP 502), 36.22 dB (VORP 503), 30.93 dB (C/MHL), 26.95 dB (SNHL), 29.95 dB (adults), 28.63 dB (children) and word recognition scores of 59.81% (ALL), 59.93% (VORP 502), 58.33% (VORP 503), 63.35% (C/MHL), 54.52% (SNHL), 59.73% (adults), 61.25% (children). Furthermore, 5 years or later after implantation the absolute mean sound field PTA4 thresholds (37.45 dB HL) and word recognition scores (66.74%) remain significantly improved over time at as tested with linear mixed-effects model (LMM) fitted with restricted maximum likelihood estimation (REML).

CONCLUSIONS: The findings of this study demonstrate that this AMEI remains safe and effective for up to 10 years with the vibrant ossicular prosthesis (VORP) 502 model and up to 5 years with the VORP 503 model.