Mastoid obliteration with hydroxyapatite vs. bone pâté in mastoidectomy surgery performed on patients with cholesteatoma and chronic suppurative otitis media: a retrospective analysis.

PURPOSE: To compare the efficacy and safety of hydroxyapatite vs. bone pâté as obliteration material in mastoidectomy surgery for patients with chronic suppurative otitis media and cholesteatoma. METHODS: This is a retrospective, multi-center, cohort study. All patients were followed up with micro-otoscopy, audiometry, and, if indicated, MRI with diffusion-weighted imaging. The following outcome parameters were analyzed: procedure safety (wound infections and complications), cholesteatoma recidivism rates (residual/recurrent), control of infection (Merchant's scale), and hearing results (pure-tone averages at 500/1000/2000/4000 Hz). RESULTS: Eighty-three cases were included: 45 obliterated with hydroxyapatite and 38 with bone pâté, with a mean follow-up time of, respectively, 25 and 24 months. Wound infections were only detected in the bone pâté group (4.8%) and successfully treated with oral or intravenous antibiotics and surgical drainage (p = 0.026). No other major surgical complications were observed in both groups. Cholesteatoma recidivism was observed in 15% using hydroxyapatite and 12% using bone pâté (p = 0.471). Complete control of infection (Merchant 0) was achieved in 76.2% using bone pâté and 86.8% using hydroxyapatite at 12 months postoperatively (p = 0.223). All patients showed good postoperative healing without complete failure to manage infection (Merchant 3). Pre- and postoperative audiometry showed significant improvement in hearing results in both groups. No significant difference between the obliteration materials was observed. CONCLUSIONS: Evaluation of mastoid obliteration reveals that hydroxyapatite and bone pâté are safe and effective obliteration materials, with high success rates in achieving a dry ear, low recidivism rates, and good hearing outcome, respecting the short-term limitation. In addition, our study shows that hydroxyapatite results in fewer postoperative wound infections compared to bone pâté.

Evaluation of the benefit for cochlear implantees of two assistive directional microphone systems in an artificial diffuse noise situation.

OBJECTIVE: People with cochlear implants have severe problems with speech understanding in noisy surroundings. This study evaluates and quantifies the effect of two assistive directional microphone systems compared to the standard headpiece microphone on speech perception in quiet surroundings and in background noise, in a laboratory setting developed to reflect a situation whereby the listener is disturbed by a noise with a mainly diffuse character due to many sources in a reverberant room. DESIGN: Thirteen postlingually deafened patients, implanted in the Leiden University Medical Centre with the Clarion CII device, participated in the study. An experimental set-up with 8 uncorrelated steady-state noise sources was used to test speech perception on monosyllabic words. Each subject was tested with a standard headpiece microphone, and the two assistive directional microphones, TX3 Handymic by Phonak and the Linkit array microphone by Etymotic Research. Testing was done in quiet at a level of 65 dB SPL and with decreasing signal-to-noise ratios (SNR) down to -15 dB. RESULTS: Using the assistive directional microphones, speech recognition in background noise improved substantially and was not affected in quiet. At an SNR of 0 dB, the average CVC scores improved from 45% for the headpiece microphone to 67% and 62% for the TX3 Handymic and the Linkit respectively. Compared to the headpiece, the Speech Reception Threshold (SRT) improved by 8.2 dB SNR and 5.9 dB SNR for the TX3 Handymic and the Linkit respectively. The gain in SRT for TX3 Handymic and Linkit was neither correlated to the SRT score with headpiece nor the duration of CI-use. CONCLUSION: The speech recognition test in background noise showed a clear benefit from the assistive directional microphones for cochlear implantees compared to the standard microphone. In a noisy environment, the significant benefit from these assistive device microphones may allow understanding of speech with greater ease.

Clinical evaluation of the Clarion CII HiFocus 1 with and without positioner.

OBJECTIVE: To study the clinical outcomes concerning speech perception of the Clarion CII HiFocus 1 with and without a positioner and link those outcomes with the functional implications of perimodiolar electrode designs, focusing on intrascalar position, insertion depth, stimulation levels, and intracochlear conductivity pathways. DESIGN: The speech perception scores of 25 consecutive patients with the Clarion CII HiFocus 1 implanted with a positioner and 20 patients without a positioner were prospectively determined. Improved multislice CT imaging was used to study the position of the individual electrode contacts relative to the modiolus and their insertion depth. Furthermore, stimulation thresholds, maximum comfort levels, and dynamic ranges were obtained. Finally, these data were associated with intracochlear conductivity paths as calculated from the potential distribution acquired with electrical field imaging. RESULTS: Implantation with a Clarion Hifocus 1 with positioner showed significantly higher speech perception levels at 3 mos, 6 mos, and 1 yr (p < 0.05) after implantation. Basally, the positioner brought the electrode contacts significantly closer to the modiolus, whereas apically no difference in distance toward the modiolus was present. Moreover, the patients with the electrode array in a perimodiolar position showed deeper insertions. The T-levels and dynamic range were not significantly different between the positioner and nonpositioner patients. Furthermore, the intracochlear conductivity paths showed no significant differences. However, a basal current drain is present for the shallowly inserted nonpositioner patients. CONCLUSIONS: A basally perimodiolar electrode design benefits speech perception. The combination of decreased distance to the modiolus, improved insertion depth, and insulating properties of the electrode array have functional implications for the clinical outcomes of the perimodiolar electrode design. Further research is needed to elucidate their individual contributions to those outcomes.