Electromagnetic semi-implantable hearing device: phase I. Clinical trials.

Conventional hearing aids have improved significantly in recent years; however, amplification of sound within the external auditory canal creates a number of intrinsic problems, including acoustic feedback and the need for a tight ear mold to increase usable gain. Nonacoustic alternatives which could obviate these encumbrances have not become practical due to inefficient coupling (piezoelectric techniques) or unfeasible power requirements (electromagnetic techniques). Recent technical advances, however, prompted a major clinical investigation of a new electromagnetic, semi-implantable hearing device.

The geriatric auditory and vestibular systems.

Age-related declines in auditory and vestibular function are becoming more prevalent and better understood. The personal and societal impact of these disorders is impressive, and present techniques of amplification or balance training can be of great benefit. However, many issues await investigation, and continued integration of ever-increasing technologies promises many new answers, and questions, in the future.

Otosclerosis masking coexistent acoustic neuroma.

The coexistence of an acoustic neuroma with otosclerosis can prove to be a great diagnostic dilemma. In such cases, the diagnosis of acoustic neuroma is usually delayed while more common causes of sensorineural hearing loss associated with otosclerosis or its surgery are considered. Any asymmetric progression of a sensorineural loss or shift in discrimination after stapes surgery, whether sudden or gradual, should provoke suspicion of a second pathologic process.

Monitoring of the glycerol test with sinusoidal harmonic acceleration in Menière's disease patients.

Changes in auditory pure tone threshold and speech discrimination and the phase and gain in the sinusoidal harmonic acceleration test were measured in subjects with endolymphatic hydrops (Meniere's disease) following the administration of glycerol. Although all subjects showed a marked improvement in auditory function, a comparable change in vestibular function, as measured by the sinusoidal harmonic acceleration test, was not observed.