Factors associated with benefit of active middle ear implants compared to conventional hearing aids

Abstract

Objective: Identify factors associated with benefit of middle ear implants (MEIs) as compared to conventional hearing aids (HAs).

Study design: Independent review of audiological data from a multicenter prospective U.S. Food and Drug Administration (FDA) clinical trial. Preoperative and postoperative earphone, unaided/aided/implanted pure-tone thresholds, and word recognition scores were evaluated.

Results: Ninety-one subjects were included in this study. Mean word recognition was better with MEIs than with HAs (81.8% ± 12.0% vs. 77.6% ± 14.6%, P = 0.035). Word recognition with MEIs showed a low positive correlation with word recognition measured with earphones (r = 0.25, P = 0.016) and a moderate positive correlation with aided word recognition (r = 0.42, P < 0.001). Earphone word recognition alone was not predictive of MEI benefit over HA benefit (r = 0.09, P = 0.41), unlike differences between scores with earphone and HAs (earphone-aided differences [EAD]) (r = 0.62, P < 0.011). As compared to those with -EADs, subjects with +EADs showed greater improvement in word recognition from unaided to implanted and from HAs to implanted (P < 0.0001). Using the 95% CI for word recognition scores, 16 subjects showed significantly higher scores with the MEI than with HAs. Of those, 14 had +EAD.

Conclusion: Word recognition benefit derived from conventional HAs and MEIs from this large, multi-center FDA trial provides further evidence of the importance of aided word recognition in clinical decision making, such as determining candidacy for and success with MEIs.

Level of evidence: 2b. Laryngoscope, 128:2133-2138, 2018.

Keywords: Middle ear implant; hearing; hearing aid; sensorineural hearing loss; word recognition.