The floating mass transducer for external auditory canal and middle ear malformations.

OBJECTIVE: The indications for the Med-El Vibrant Soundbridge, currently limited to patients with sensorineural hearing loss and normal middle ear function, have been extended to include patients with conductive or mixed hearing loss because of severe acquired or congenital ossicular chain defects. Patients with congenital aural atresia have combined malformations of the external auditory canal and the middle ear, often accompanied by severe mixed hearing impairment. Long-term results of traditional surgical techniques for treatment of congenital aural atresia show a persistent air-bone gap in most patients, suggesting that new and better techniques for hearing rehabilitation in these patients would be of value. This study demonstrates that placement of the floating mass transducer of the Med-El Vibrant Soundbridge on the round window (RW) allows optimal amplification and enables the restoration of good hearing in these patients.

STUDY DESIGN: Retrospective case review.

SETTING: Tertiary referral center.

PATIENTS: The study population comprised 12 patients-5 adults and 7 children-with severe external auditory canal and middle ear malformations. The patients were either judged not to be candidates for air conduction hearing aids or declined bone conduction and Bone-Anchored Hearing Aids.

INTERVENTION: RW implantation.

MAIN OUTCOME MEASURES: Pure-tone threshold and speech understanding.

RESULTS: Significant improvements were observed in pure-tone threshold and speech understanding immediately after surgery and at follow-up intervals ranging from 12 to 48 months. No complications or instances of device extrusion were observed in these patients.

CONCLUSION: The results suggest that RW implantation offers a viable and improved treatment option for patients with severe mixed hearing loss and congenital malformation of the outer and middle ear.