Round window application of an active middle ear implant (AMEI) system in congenital oval window atresia.

CONCLUSION: Application of the Vibrant Soundbridge to the round window (RW) membrane can be utilized as an efficient therapy for congenital oval window (OW) atresia.

OBJECTIVE: To report the surgical technique and auditory outcome of an active middle ear implant (AMEI) system used in patients with congenital OW atresia.

METHODS: Nine subjects with congenital OW atresia (six males and three females, ranging in age from 5.5 to 25 years, average 12.5 years) were implanted with an AMEI (Vibrant Soundbridge) at the round window (RW-Vibroplasty). Five cases were diagnosed as having isolated congenital OW atresia while four patients presented with combined external/middle ear malformation.

RESULTS: An improvement of 30 dB in average pure-tone air conduction thresholds (0.5-4 kHz) was achieved, with the high frequencies showing greater results. The subjects achieved postoperative speech recognition scores of 80-100% on the Computerized Mandarin Speech Test System (CMSTS) sentence test. Bone conduction thresholds were confirmed as stable in all subjects postoperatively. Decline in auditory benefit was noticed in two subjects, who then underwent revision surgery. One of these revision surgery patients then experienced stable hearing recovery, while the other patient's hearing declined.