Long-Term Follow-Up in Active Transcutaneous Bone Conduction Implants.

Objective: To evaluate long-term outcomes of active transcutaneous bone conduction implants (atBCIs) regarding safety, hearing, and quality of life.

Study Design: A clinical study with retrospective medical record analysis combined with prospective audiometry and quality of life questionnaires.

Setting: Three secondary to tertiary care hospitals.

Patients: All subjects operated with an atBCI in three regions in Sweden were asked for informed consent. Indications for atBCI were single-sided deafness (SSD) and conductive or mixed hearing loss (CMHL).

Intervention: Evaluation of atBCI.

Main Outcome Measures: Pure tone and speech audiometry and Glasgow Benefit Inventory (GBI).

Result: Thirty-three subjects were included and 29 completed all parts. The total follow-up time was 124.1 subject-years. Nineteen subjects had CMHL and in this group, pure tone averages (PTA4) were 56.6 dB HL unaided and 29.6 dB HL aided, comparable with a functional gain of 26.0 dB. Effective gain (EG) was -12.7 dB. With bilateral hearing, Word Recognition Scores (WRS) in noise were 36.5% unaided and 59.1% aided. Fourteen subjects had SSD or asymmetric hearing loss (AHL) and in this group, PTA4 were >100 dB HL unaided and 32.1 dB HL aided with the contralateral ear blocked. EG was -9.1 dB. With bilateral hearing, WRSs were 53.2% unaided and 67.9% aided. The means of the total GBI scores were 31.7 for CMHL and 23.6 for SSD/AHL.

Conclusion: Few complications occurred during the study. The atBCI is concluded to provide a safe and effective long-term hearing rehabilitation.