Martin Evert Gustaf Hillbratt

Improving the Accuracy of Baha® Fittings through Measures of Direct Bone Conduction.

Objectives Variability in Baha® sound processor fittings may arise from the nature of the implant-to-bone transmission as well as transcranial attenuation for patients with single-sided sensorineural deafness (SSD). One method of improving the predictability of Baha fittings is to measure the individual patients actual bone conduction thresholds, thereby removing the influences of skin thickness and/or the implant location site. Methods Twenty adult wearers of the Baha bone conduction implant system participated in the study. Direct bone conduction thresholds were obtained through the BC Direct function of the Baha Fitting Software combined with the Cochlear Baha BP100 sound processor. For comparison, the masked and unmasked bone conduction responses of the patients were collected through standard audiometric testing techniques. Test-retest reliability measurement was performed for all participants. Data for each frequency and frequency range were analyzed separately. Results The results confirm the improved transmission of sound through the implant rather than transcutaneously through the skin. On average, the BC Direct thresholds were closer to the patients unmasked thresholds than the masked values. In subjects with SSD, BC Direct results were poorer than contra-lateral bone conduction thresholds, most likely due to transcranial attenuation. The test-retest reliability for the BC Direct measurements was within +/-5 dB. The comparison of preferred amplification, based on direct bone conduction or bone conduction audiometry, found higher agreement for fittings based on direct bone conduction measurements. Conclusion While the transfer function between the implant and the skin can be predicted on average, there are a number of patients for whom measurement is essential to determine the required amplification. These were patients with: 1) SSD, 2) asymmetrical hearing loss, 3) unusual implant location or skull formation, and 4) users of Testband or Softband. The result for the clinician is that a fitting can take place with less fine-tuning and a greater understanding of the variability of bone conducted sound transmission.

A new antistuttering device: treatment of stuttering using bone conduction stimulation with delayed temporal feedback.

Objectives: Stuttering is a communication disorder affecting approximately 1% of the adult population, some with severe manifestations. Speech therapy improves stuttering, but many do not receive enough benefit to communicate fluently. Antistuttering devices have been available for several years, but available technology has been limited in long‐term success and reliability. The current study evaluates the effects of a prototype device using a modification of a currently used bone conduction hearing device with delayed auditory feedback on adult patients with significant stuttering problems.