Kiyomitsu Asahi

Tympanometric Findings in Patients With Enlarged Vestibular Aqueducts

Objectives The purpose of this study was to study systematically some relationships between the resonance frequency of the middle‐ear transmission system and the volume of the endolymphatic duct and sac in patients with an enlarged vestibular aqueduct (EVA).

Factors affecting hearing results after stapes surgery

Factors affecting auditory improvement after stapes surgery were investigated retrospectively on a study group of 106 otosclerotic ears (86 subjects). While the closure of the air-bone (A-B) gap after surgery was good at 2 kHz and 4 kHz, it was poor at 8 kHz and at frequencies lower than 1 kHz. Under 1 kHz, the lower the frequency, the worse the A-B gap after surgery. Stapedotomy and partial stapedectomy showed better post-operative hearing gain at 4 kHz than total stapedectomy. Total stapedectomy scored significantly better at 250 Hz and 500 Hz than stapedotomy. There was a close relationship between the pre-operative and post-operative A-B gap at frequencies under 1 kHz. The smaller the pre-operative A-B gap, the better the closure of the post-operative A-B gap at these frequencies. It was speculated that otosclerotic ears with a larger pre-operative airbone gap might have another lesion in the middle ear other than the oval window.

Transmeatal low-power laser irradiation for tinnitus.

Objective To evaluate effectiveness of 60-mW laser irradiation in the treatment of tinnitus. Study Design Prospective, randomized double-blind study. Methods This investigation included 68 ears in 45 patients with disabling unilateral or bilateral tinnitus. The active or placebo laser treatment was administered transmeatally once a week for 6 minutes. Laser irradiation was performed four times during a 4-week period. A questionnaire was administered to evaluate the loudness, duration, quality, and annoyance of tinnitus before and after irradiation. The loudness and pitch match for tinnitus were obtained, and distortion product otoacoustic emissions were also examined. Results No significant difference was observed between the active and placebo laser groups with regard to outcome of loudness, duration, quality, and annoyance of tinnitus. In one patient who received active laser treatment, acute hearing deterioration occurred after the third irradiation. Conclusion Transmeatal low-power laser irradiation with 60 mW is not effective for the treatment of tinnitus.

Cochlear blood flow and speech perception ability in cochlear implant users.

Objective The effect of cochlear blood flow (CBF) on speech perception ability in cochlear implant (CI) users has not been reported. We investigated various factors influencing speech perception including CBF in CI users. Patients Eighty-two patients who received CI surgery at an academic hospital. Methods CBF was measured during CI surgery using laser Doppler flowmetry. The speech perception level was measured after a sufficient interval after CI surgery. Multivariate analysis was used to evaluate the influences of age, duration of deafness, sex, cause of deafness, and CBF on the speech perception level. Results CBF decreased significantly with age but was not related to the speech perception level. In patients with congenital hearing loss, the speech perception level was significantly worse in children who received a CI at 3 years of age than in those who received a CI at 2 years of age or younger. Duration of deafness before CI surgery had deteriorative effects on the speech perception level. Conclusion CBF may be associated with progression of hearing loss. However, measuring CBF during CI surgery is not useful for predicting postoperative speech perception.