Long-term results and experience with the first-generation semi-implantable electromagnetic hearing aid with ossicular replacement device for mixed hearing loss.

OBJECTIVE

To document the long-term surgical and audiologic results of the implantation of a first-generation semi-implantable hearing aid for mixed hearing loss, consisting of a magnetic partial or total ossicular replacement prosthesis and an electromagnetic driver fitted in the ear canal. The short-term results have previously been published as excellent in both surgical and audiologic terms. To analyze and discuss reasons of treatment failure, as well as future perspectives.

STUDY

DESIGN

Patient file review, follow-up otomicroscopic examination and audiometry, as well as patient interview. SETTING Tertiary referral center at a University hospital.

PATIENTS: Of nine patients operated on, six with a mixed hearing loss after chronic otitis media could be evaluated primarily. Two underwent implantation with a partial and four with a total ossicular replacement prosthesis.

MAIN OUTCOME MEASURES: Use of and satisfaction with the hearing aid, apparatus function and integrity, hearing without electromagnetic driver, prostheses containment, drum abnormalities, nonaudiologic ear symptoms, e.g., discharge.

RESULTS

All patients attended follow-up for a mean of 9.5 years after implantation (range 8.8-10 years). No patients used the semi-implantable hearing aid at follow-up. The mean semi-implantable hearing aid using time was 24 months (range 3-60 months). The main reasons for discontinuation of use were problems fitting the electromagnetic driver correctly in the ear canal and prosthesis extrusion or dislocation.

CONCLUSIONS

Despite excellent short-term surgical and audiologic results, it is concluded that these first long-term results of the first-generation electromagnetic semi-implantable hearing aids with ossicular replacement prosthesis for mixed hearing loss are disappointing. However, improvements in the surgical approach and in the reshaping, refinement, and overall improvement of the semi-implantable hearing aid could lead to satisfactory treatment of this group of patients.