Speech discrimination in background noise with the Vibrant® Soundbridge™ middle ear implant

Objective: Evaluate speech intelligibility in competing background noise for monaural users of the Vibrant® Soundbridge™ (VSB) middle ear implant (Symphonix). Patients and Material: Nine adults with moderate to severe bilateral sensorineural hearing loss, and implanted with a unilateral VSB, were included in the study. The patients' experience of the implant ranged from 9 to 24 months. Retrospective single-subject repeated measures of speech intelligibility in background noise were performed using 2 different test procedures, the Elbaz test and the Garin and Galle test. The patients were tested VSB aided and VSB unaided in a variety of signal-to-noise ratios. The correct-score percentage for each ratio for each condition was averaged for the group of patients and compared with normative data for each test method. Results: The VSB-aided condition showed results approaching normative data for both test methods. At a signal-to-noise ratio of zero, the Elbaz test showed a mean correct score of 55% for the VSB-unaided condition versus 85% for the VSB-aided condition. The Garin and Galle test showed a mean score of 34% for the VSB-unaided condition versus 94% for the VSB-aided condition. Conclusions: Although the unilateral VSB middle ear implant does not restore stereophony, it does improve speech intelligibility in background noise.