Biomedical subjects

K Mizukoshi

Publications and source records attributed to K Mizukoshi.

At least 37 records · Page 2Linked to original sources

PubMed1993

Glycoconjugates in the vestibular organs as revealed by the silver methenamine method.

The glycoconjugates in the vestibular organs of the guinea pig were studied after staining by the silver methenamine method and by the periodic acid-Schiff (PAS) reaction. The organic matrix of otoconia, otolithic membranes and cupulae were stained to the same degree by the PAS reaction. In contrast, the mineralizing and non-mineralizing matrices were clearly distinguished by the silver methenamine method. The otoconia were surrounded by an intensely stained organic matrix, while the otolithic membranes and cupulae were moderately stained. This histochemical difference suggests that the positively stained organic matrix of otoconia is not identical to the otolithic membranes and cupulae in terms of its biochemical composition. The strongly stained material may play an important role in turnover of calcium in otoconia. The contact areas between type I hair cell and nerve calyx were contained silver methenamine-positive material which is probably involved in adhesion of these cell membranes.

Animals↗

PubMed1993

Clinical significance of the galvanic body sway test in cerebellopontine angle tumors.

Since 1984, we have been modifying a new method of recording fine body sway elicited by low current stimuli of less than 0.4 mA, and of quantitatively evaluating the responses by Fourier transform. In order to easily and early detect acoustic tumors, we have applied a test battery consisting ABR, caloric test and galvanic body sway test (GBST) to 31 cases with acoustic neurinoma, to 5 cases with other CPA-tumors, and to 24 cases suspected of having CPA tumors. Of 27 cases with acoustic neurinoma on whom the GBST was performed, 25 cases (92.6%) shows abnormal responses. On the other hand, the ABR was abnormal in all cases, except for one case in the early stage of an ear tumor. However, the ABR was positive in 12 cases out of 24 with suspected findings without tumor, but the GBST was positive in only 3 cases out of 17 tested. Moreover, 26 cases (83.9%) with acoustic tumors showed abnormal CP in their first caloric tests. Comparing these observations with the results of image diagnosis, we conclude that the GBST is as useful for detecting small acoustic neurinomas as the ABR and the carloric test. Therefore, we have routinely used a test battery consisting ABR, caloric test and GBST for evaluation of acoustic neurinomas. However, we could not differentiate between acoustic neurinoma and CPA-tumor by using the three-test battery.

Auditory Threshold↗

PubMed1993

Quantitative evaluation of the function of looking at visual target in optokinetic nystagmus.

A new method is presented to qualitatively evaluate the function of OKN which certainly looks at a visual target. Optokinetic stimulation was given to a test subject by projecting stripes with a 5 degrees visual angle width at 30 degrees intervals, which was accelerated by 1 degree/s2 up to 100 degrees/s. The correlation between slow phase and fast phase was computed with our program. Two correlations were mixed in a normal response, one indicated low correlation and the other high correlation. As normal subjects look at wide interval visual targets one by one regardless of the target velocity, low correlation type OKN beats are considered to be those which certainly look at the visual target. In order to quantitatively analyze this type of OKN, approximate regression lines of the low correlation type, [y = ax + b (x: slow phase velocity, y: fast phase amplitude or velocity)], were computed by the minimum square method. In normal subjects, value a indicates low and value b high velocity and their normal limits are determined. The results of cases with central disequilibrium indicate that this analysis provides information of pathological OKN different from that of such conventional parameters as slow phase velocity and number of nystagmus beats.

Dominance, Cerebral↗

PubMed1993

Otoconia in young and elderly persons: a temporal bone study.

Using serially sectioned human temporal bones, the volumes of otoconia masses were compared between young children and elderly people. The latter group had significantly less otoconia volume than the former group, both in the macula utriculi and macula sacculi. The ratio between macula utriculi and macula sacculi was 100:70 in the young group, whereas it was 100:35 in the elderly group. Thus, the macula sacculi in the elderly group showed the severest otoconia reduction.

Aged↗

PubMed1993

Salivary total protein and experimental Coriolis sickness.

Symptomatic reporting has been used in quantifying the severity of motion sickness including Coriolis sickness. This study was designed to objectively examine if the dynamic changes of salivary protein concentration relate to the severity of Coriolis sickness. Healthy adults with normal vestibular function underwent a modified Coriolis Sickness Susceptibility Index (CSSI) test, utilizing a staircase profile. Salivary samples were obtained prior to stimulation, 15, 30, and 45 min following stimulus onset, and/or upon reaching "nausea-II" endpoint. Total protein concentration tended to rise over the initial 30 min of stimulation, and then level off or decline. A statistically significant difference was found between the pre-stimulation and 30 min samples. Although some variability existed among the subjects, the general pattern of changes along the time course was similar. An inverse correlation approaching statistical significance was found between control (non-stimulus) total protein levels, and minutes of Coriolis stimulation required to reach the "nausea-II" endpoint. Thus, baseline salivary total protein levels can be of use in predicting susceptibility of Coriolis sickness and other forms of motion sickness.

Adult↗

PubMed1993

Effect of transdermally administered scopolamine on the vestibular system in humans.

In order to elucidate the effect of scopolamine on the vestibular system in humans, various experimentally-induced forms of nystagmus, i.e. caloric nystagmus, rotational nystagmus, optokinetic nystagmus, visual-vestibular interaction and optokinetic after nystagmus, were evaluated before and after the administration of two pieces of Scopoderm-TTS or placebo patches retro-auricularly. Scopolamine reduced the responses of both the caloric and optokinetic after nystagmus compared with the placebo. The possible action site of this drug is discussed.

Administration, Cutaneous↗

PubMed1993

The intravenously administered glycerol test.

Three different methods of performing the glycerol dehydration test were evaluated. Method one involved the oral administration of 50 g of 50% glycerol solution; method two was the intravenous administration of 500 ml of 10% glycerol in saline with 5% fructose; and method three involved the administration of 200 ml of the same solution. It was found that intravenous administration was safe and did not give any unpleasant side effects. Both intravenously administered methods appeared to give similar rates of positive diagnosis for Menière's disease.

Administration, Oral↗

PubMed1993

Furosemide VOR test for the detection of endolymphatic hydrops.

In order to detect endolymphatic hydrops, we applied three neuro-otologic examination methods, including the furosemide VOR test, the glycerol dehydration test, and electrocochleography in 61 patients with unilateral Menière's disease, 21 patients with delayed endolymphatic hydrops, and 10 patients with syphilitic labyrinthitis. The positive rate of the furosemide VOR test in patients with endolymphatic hydrops was more than 50%. Inconsistencies were observed between the results of the furosemide VOR test, the glycerol test and/or electrocochleography. Therefore, combined test battery of these tests is useful clinically for detecting endolymphatic hydrops in the vestibular and cochlear systems.

Edema↗

PubMed1993

Electrocochleography in syphilitic hearing loss.

Syphilitic labyrinthitis presents such symptoms as hearing loss, tinnitus, vertigo and/or dizziness, and is well known as one of the endolymphatic hydropic diseases. In order to elucidate the relationship between syphilitic hydrops and ECochG findings, we performed ECochG in patients with syphilis following our previously reported study of patients with Meniere's disease. Twenty-two patients who have been serologically and clinically diagnosed as having syphilitic labyrinthitis were examined with ECochG between December, 1982 and November, 1991. Of the 27 ears tested with ECochG, 2 showed no response due to severe hearing loss, and increased SP (SP/AP ratio > 0.37) was observed in 14 (56.0%) out of the remaining 25 ears. The SP/AP ratio of patients with syphilitic labyrinthitis was not significantly different from that of the patients with Meniere's disease or delayed endolymphatic hydrops, while it was significantly higher than that of the patients with sudden deafness and other types of sensorineural hearing loss. We conclude that the electrocochleographic features of endolymphatic syphilitic lesions resemble those in Meniere's disease.

Adult↗

PubMed1993

Effects of isosorbide in patients with Menière's disease.

The effects of isosorbide on vertigo, disability, hearing loss and tinnitus in 32 patients with Menière's disease were evaluated after a 24-month observation period. Vestibular symptoms in 80% of patients were assessed as improved according to the 1985 AAO-HNS post-treatment reporting criteria. In contrast, the effect of this osmotic diuretic on cochlear symptoms was limited.

Administration, Oral↗

PubMed1993

Changes in auditory evoked responses during intravenous lidocaine.

Auditory evoked responses in 21 cases with tinnitus were recorded before and after the administration of intravenous lidocaine. A dosage of 1 mg/kg body weight was diluted with 20% glucose (20 ml) and administered intravenously over a one-min period. The loudness of tinnitus was evaluated during electrocochleography (ECochG) or auditory brain-stem response (ABR) recordings using a score between 0 and 11. The stimulus sound was a tone burst in a frequency that corresponded to the pitch of tinnitus. AP latency on ECochG and the inter peak latency (IPL) of wave I-III and wave III-V on ABR were prolonged momentarily and tinnitus was reduced. These findings reveal that the sites of action for lidocaine are both the inner ear and the brain-stem.

Audiometry, Evoked Response↗

PubMed1993

Neurotological findings in patients with acute mumps deafness.

We report the neurotological findings in 4 cases of acute stage hearing loss due to mumps. In 2 of the cases, the less severe hearing loss which occurred in the opposite ear was shown to have improved after therapy. If patients with mumps suffer from a mild hearing loss which recovers quickly, the temporary auditory problem might go undiagnosed; thus the incidence of mumps deafness might well be higher than that reported in the literature. Two of our patients complained of dizziness. In the caloric test, a reduced response of the ear with poorer hearing was found in 3 cases, and a normal caloric response was revealed in the fourth. In the galvanic body sway test (GBST), 3 cases showed a normal response bilaterally and one case presented a normal response bilaterally in the first test, no response in the right side in the second test, and recovery of response in the third test. These findings suggest that an inner ear disorder might occur in combination with a retrolabyrinthine disorder in mumps deafness, with the former lasting longer and the latter improving earlier.

Adult↗

PubMed1993

Clinical usefulness of the personal computer for equilibrium examinations.

A personal computer (PC) system and its usefulness for equilibrium examinations is reported. The system was introduced into clinical routine practice for the following purposes: i) Reduction of test result measurement troubles in clinical practice, ii) Clearer observation of eye movements and body sway, iii) Quantitative analysis of nystagmus responses or body sway, iv) Easy introduction into clinical practice of new parameters or new tests, v) Programmable arrangement of stimulating devices, and vi) Effective storage of test data. Our PC system has been successful for these purposes and provided many useful options in equilibrium examinations. Although computer systems for equilibrium examination have not been popular due to high costs, the PC system, which can be obtained at a reasonable price, has become as powerful a device as the conventional small computer, and is expected to become a popular method for both research and routine clinical practice in the near future.

Caloric Tests↗

PubMed1993

Body sway response to experimental unbalance in normal subjects and patients with unilateral vestibular disorders.

The function of maintaining posture during temporary unbalance caused by experimental vestibular asymmetry was studied. Galvanic stimulation to the vestibular nerve causing body deviation to the stimulated ear was given to 31 normal subjects and 16 patients with peripheral vestibular disorders. The velocity of spontaneous body sway and that during body deviation caused by the galvanic stimulation were compared. The spontaneous body sway velocity was significantly higher than that of normal subjects. In normal subjects, the body sway velocity during body deviation remarkably increased, while that in patients did not. It is considered that large body sway in patients might conceal the fine compensatory body sway during the body deviation and that patients with unilateral vestibular dysfunction who have large body sway are always in a dysfunction state similar to that which normal subjects experience during body deviation caused by galvanic stimulation.

Dominance, Cerebral↗

PubMed1993

Vestibular nerve disorder in patients suffering from sudden deafness with vertigo and/or vestibular dysfunction.

Vestibular nerve disorder (VND) in cases suffering from sudden deafness with vertigo was studied. Between 1987 and 1991, we observed 46 patients suffering from sudden deafness with or without vertigo, who had undergone the caloric test and galvanic body sway test (GBST). Twenty-seven patients had vertigo and canal paresis (CP) upon the caloric test, 6 vertigo without CP and 13 CP without vertigo. VND was detected in 12 of the 46 patients. All those with VND had vertigo and CP upon the caloric test, 12/27 (44%). The degree of hearing loss in those with VND was significantly (p < 0.05) more severe and their recovery of hearing loss was poorer than in patients without VND. These results indicate that VND is a common finding in cases of sudden deafness with vertigo especially in those with severe hearing loss.

Caloric Tests↗

PubMed1993

The contribution of proprioception to posture control in normal subjects.

In order to investigate the contribution of proprioceptive input to maintaining an upright position, stabilometry via 100-Hz vibratory stimulation applied to the Achilles tendon was studied and analyzed with respect to area, length and power spectra according to the method of fast Fourier transform (FFT). Twenty-one young medical students were analyzed in this study. When vibration was applied, the body sway was significantly greater than that of control in area and length with both eyes open and closed. There was a significant increase of total power in both the lateral (X) and antero-posterior (Y) directions with the eyes closed. With the eyes open, an increase was found only in the antero-posterior direction. The frequency band indicating the maximum spectrum did not shift. Significant increases in power spectra were found in the frequency range of more than 2 Hz in both two directions with the eyes closed. It was concluded that a vibration given to the Achilles tendon provoked a pronounced high frequency body sway especially in the antero-posterior direction when visual information was nullified, and that proprioceptive information may have a minor role compared with visual information.

Achilles Tendon↗

PubMed1993

Evaluation of vestibular function by dynamic posturography and other equilibrium examinations.

We evaluated the significance of dynamic posturography (EquiTest) in vestibular function assessment by comparing it with our routine equilibrium examinations comprised of nystagmographic data and other postural tests. Fifty-two patients with unilateral peripheral vestibular disorders were examined. Differences in test results between pendular rotation test and dynamic posturography were found in 23 out of 52 (44%) patients with unilateral peripheral vestibular disorders. In 5 patients, no abnormality of vestibular function could be detected by means of a three-test battery (spontaneous and positional nystagmus and pendular rotation test) used for evaluating vestibular compensation. In spite of these results, the patients complained of vertigo of dizziness and showed abnormal results in dynamic posturography. Dynamic posturography was superior to other postural tests in the detection of pathology corresponding with the patients' complaints. From these results, dynamic posturography (EquiTest) appeared to provide new information about such conditions of vestibular patients which other equilibrium examinations have not heretofore been able to detect.

Adult↗

PubMed1993

A case of Bickerstaff's encephalitis. With special reference to neurotological findings.

The case of a 60-year old male with prodromal common cold symptoms and progression of brain stem involvement with no cardiac or respiratory complications is described. This conformed to the criteria of Bickerstaff's encephalitis. Neurotological examinations, including the OKN test, the caloric test, and the GBST were performed from onset to recovery of the disease. The results of these tests closely reflected the central nervous system disorders each time, but there was a discrepancy in the results of the two test batteries of equilibrium function, the caloric test and the GBST. The caloric test showed bilateral canal paresis while the GBST showed normal responses. These results suggested that the involved area of the vestibular nucleus was localized to the superior portions. Form our clinical observations, we can conclude that neurotological examinations provide more vital information for localized diagnosis and follow-up of the brain stem lesion in Bickerstaff's encephalitis.

Brain Stem↗