PubMed · 4732607
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
D R Perrott, P Higgins. 1973. Notes on the electrophonic hearing effect.. https://doi.org/10.1121/1.1913491
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
We report a series of 100 stapes operations performed for otosclerosis. The problems in reporting the results of stapedectomies are discussed. The audit showed a difference in the measured results between two consultants. As a result, the consultant with the worse outcome chose to stop operating on patients with otosclerosis. The advantages and disadvantages of a single surgeon performing all the cases are discussed. We advocate a central registry of all surgeons performing stapes surgery to allow periodic national comparative audits.
Measurement of the motion of the malleus umbo and stapes footplate during bone conduction (BC) stimulation was conducted in vitro in 26 temporal bones using a laser Doppler vibrometer over the frequency range 0.1 to 10 kHz. For lower frequencies, both ossicular sites followed the motion of the temporal bone. The differential motion between the malleus and the surrounding bone was greater than the differential motion of the stapes footplate; both resonated near 1.5 kHz. Different lesions were shown to affect the response: (1) a mass attached to the umbo lowered the resonance frequency of the ossicular vibration; (2) fixation of either the malleus or stapes increased the stiffness and shifted the resonance frequency upward; and (3) dislocation of the incudo-stapedial joint did not significantly affect the ossicular vibration. The sound radiated from the tympanic membrane was approximately 85 dB SPL at an umbo differential velocity of 1 mm/s for low frequencies in an open ear canal and about 10 dB higher for an occluded one; at higher frequencies (above 2 kHz) resonances of the canal determine the response. It was also found that the motion between the footplate and promontory was within 5 dB when the specimen was stimulated orthogonal to the vibration direction of the ossicles than in line with the same. Measurement of the differential motion of the umbo in one live human skull gave similar response as the average result from the temporal bone specimens.
The authors presents hearing results in 216 patients with otosclerosis surgical treated. Averaged cochlear reserve in relation to the bone conduction determined before operation was used in this study. The follow-up was 2 months-10 years. Good results was proved in more than 93%, no change in 5% and deterioration in less than 2%. The cochlear reserve up to 10 dB obtained in 59% of all patients. The cases when no changes (and deterioration) after surgical treatment correlated to large anomaly evolution in the structure of the hole drum and extensive focus with otosclerosis.