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Biomedical subjects

H Nishida

Publications and source records attributed to H Nishida.

At least 505 records · Page 28Linked to original sources
PubMed1982

Electrocochleographic study of Ménière's disease.

Auditory nerve action potential (AP), cochlear microphonics (CM), and summating potential (SP) were recorded from 32 patients with Ménière's disease. Patients were classified into three groups according to the degree of their hearing impairment. The group of patients that had a mild to moderate hearing loss and whose hearing was reversible showed notably satisfactory responses for AP, CM, and negative SP (-SP), and also showed a high incidence of positive SP (+SP). Low responses for AP and CM with an increase of detection thresholds and a high -SP/AP ratio were obtained from patients with moderate hearing impairment, whose hearing fluctuated slightly. These electrocochleographic findings were suggestive of the pathophysiologic differences at the various stages of Ménière's disease.

Audiometry, Evoked Response↗
PubMed1981

Electrocochleographic study of patients with cerebral vascular lesions.

Electrocochleographies were performed on three patients with deafness resulting from cerebral vascular lesions. Recording was made by the transtympanic needle electrode technique. In a patient who had anterior-inferior cerebellar artery aneurysm that showed fluctuating hearing loss, auditory nerve action potential (AP), cochlear microphonics (CM), and summating potential fluctuate in amplitude in concert with episodes of ischemic hearing loss. This indicates the pathophysiology of reversible impairment of the cochlear nerve and of sensory epithelium of the inner ear caused by disturbance of blood flow into the inner ear. It was also conjectured that the cochlea is hardly impaired in the case with normal AP and CM responses despite the increased threshold in pure-tone audiometry and that the cochlea undergoes irreversible organic changes in the patient who has no AP or CM response in tests after a long period.

Action Potentials↗
PubMed1981

Changes of the action potential, the summating potential and cochlear microphonics in experimental endolymphatic hydrops.

The changes of the action potential (AP), the summating potential (SP) and cochlear microphonics (CM) were investigated in reference to the grade of endolymphatic hydrops produced by endolymphatic sac obliteration in guinea pigs. In a few cases with minimum endolymphatic hydrops, super-normal AP was obtained. With an increase of endolymphatic hydrops, CM responses were reduced although AP responses at intensive stimulation were maintained relatively well. It is thought that the polarity of positive SP, as observed in control, was influenced to deflect towards negative SP by an interaction between the increased degree of endolymphatic hydrops and the changes of the biochemical components of the inner ear fluids.

Action Potentials↗
PubMed1980

Experimental labyrinthine disorders and direction of nystagmus.

The purpose of this paper is to demonstrate the variation of the direction of nystagmus which is elicited from the peripheral labyrinth. The direction of nystagmus depends, among other things, on the nature of the stimulus. Depending on the degree of pathophysiological conditions in the labyrinth, atypical nystagmus which does not comply with the rule is occasionally elicited even though the same stimulus is given. Hyperfunctional stimulation to the labyrinth, such as allergy, causes nystagmus which beats to the affected side and also shows hyperactivity of the whole nerve action potential and cochlear microphonics.

Animals↗
PubMed1980

Regional difference in susceptibility to damage of vestibulo-semicircular canals in experimental labyrinthine lesion.

In the study on regional difference in susceptibility to damage of vestibulo-semicircular canals upon causing labyrinthine lesion by four different procedures, namely, by intracranial approach, through the middle ear, through the facial nerve and by means of experimental endolymphatic hydrops, the following results were obtained. 1. The crista of posterior semicircular canal among the semicircular canals and the macula of the saccule within the vestibule were most susceptible to impairment. In other words, the most susceptible region was the so-called pars inferior. In regard to the impairment of the cupulas, the posterior semicircular canal was the most susceptible region. 2. Recovery from markedly reduced caloric nystagmus within a short period so as to see provocation of caloric nystagmus may result from the reconstruction of the cupulas and the normalization of vacuole-like findings of the sensory epithelium.

Animals↗