SS06: ACTIVE MIDDLE EAR IMPLANTS AND MHL

VIBROPLASTY SURGERY, SURGICAL ASPECTS AND AUDIOLOGICAL RESULTS

Colletti V

ENT Department, University of Verona, Italy.

Background: Over the last five years the application of the MED-El Vibrant Soundbridge has been extended to patients with more or less severe ossicular chain defects obtaining marginal benefit from traditional middle ear surgery. Several clinical studies have investigated the various middle ear sites where to position the floating mass transducer (FMT) in order to optimize the sound transmission to the cochlea: direct stapes stimulation, stimulation via a partial or total ossicular replacement prosthesis, and direct round window stimulations (Colletti et al., 2005; Needham et al., 2005; Colletti et al., 2006: Huber et al., 2006; Kiefer et al., 2006; Wollenberg et al.,2007; Huttenbrink et al., 2008).
Round window implantation (RWI) bypasses the normal conductive path and provides amplified input to the cochlea.

Patients: Thirty-eight patients with bilateral moderate to severe mixed or conductive acquired hearing loss without cholesteatoma and bilateral ossicular chain erosion (footplate residual) were alternately assigned to a titanium-TORP (T-TORP) or to RWI. The results for the two groups were statistically analyzed at 36 months postoperatively. The following postoperative anatomic conditions were also evaluated: 1) recurrence of infection, 2) retraction pocket, 3) extrusion rate, and 4) displacement of the prosthesis.

Results: Good functional results and stability at 36 months were obtained with either procedure. Hearing results were statistically better for RWI versus T-TORP. These results suggest that RWI may offer a viable treatment option for individuals with severe mixed hearing loss who have undergone unsuccessful ossiculoplasties.

Conclusion: Round window implantation may be suggested as the first choice in hearing rehabilitation for patients with chronic otitis media and extensive destruction of the ossicular chain.