Retrospective Analysis of Hearing-Impaired Adult Patients Treated With an Active Transcutaneous Bone Conduction Implant.

OBJECTIVE: To determine the therapeutic success and safety of an active transcutaneous bone conduction implant (tBCI) in adult patients with conductive or mixed hearing loss.

STUDY DESIGN: Retrospective case review.

SETTING: Five university hospitals in Frankfurt, Hannover, Dresden, Würzburg, and Vienna.

PATIENTS: Data were analyzed from 61 patients (31 women, 30 men) with a mean age of 50 years (min. 26, max. 80). Forty patients had mixed, and 21 conductive hearing loss. Typical etiologies were history of otitis media (n = 20) and cholesteatoma (n = 17).

INTERVENTIONS: Implantation of the active tBCI.

MAIN OUTCOME MEASURES: Data were analyzed for the following time points: up to 6 months postoperatively ("short-term"), 6 to 37 months postoperatively ("long-term"), and the last available measurement per patient ("most recent"). Pure-tone audiometry (air and bone conduction, AC and BC) and sound field thresholds with warble tones (WT), word recognition scores with Freiburger monosyllables (WRS), as well as speech reception thresholds (SRT) using the Oldenburg sentence test (OLSA) in quiet (SRT) and in noise (signal-to-noise ratio, SNR) were collected.

RESULTS: No significant changes in air- and bone-conduction thresholds were observed after implantation. A mean WRS improvement of 54% using the active tBCI was shown at the short-term assessment, i.e., a mean score of 79% compared with 25% in the unaided condition. Results remained stable, with a mean score of 75% at the long-term assessment. SRT in noise improved by 3.6 dB SNR in the implanted ear at the short-term assessment. Overall six adverse events and four serious adverse events were reported, resulting in a rate of 9.84 and 6.56%, respectively.

CONCLUSION: The tBCI clearly improves speech intelligibility in patients with conductive or mixed hearing loss, showing stable results up to 1 year post-implantation.