Yoshiyuki Kitaoku

Four cases of vertebrobasilar insufficiency.

Four cases of vertebrobasilar insufficiency are reported. Case 1 was a 38-year-old man who felt a sudden onset of dizziness when he turned his head to the back. An abnormal positional nystagmus was observed when he rotated his head to the left. A magnetic resonance angiogram (MRA) demonstrated total occlusion of the left vertebral artery (VA). Case 2 was a 31-year-old woman who had a total occlusion of her left VA as observed in the MRA. Case 3 was a 68-year-old man who noted dizziness. The systolic blood pressure change on his Schellong test was 28 mmHg. On his MRA, severe displacement of the basilar and the vertebral arteries was visible. Case 4 was a 76-year-old woman who noted a blackout-like sensation. Optokinetic nystagmus was noted with a hyponystagmus pattern, and an eye tracking test showed a saccadic pattern. On her MRA, the vertebrobasilar system was narrowed. The arterial architecture and any stenosis of the blood vessels could be detected non-invasively by MRA.

MR-angiographic Findings of Patients with Central Vestibular Disorders

Magnetic resonance angiography (MRA) is a new, noninvasive, and useful method to estimate the posterior circulation in patients with vertigo. From June 1995 to May 1997, 180 patients were examined by magnetic resonance imaging (MRI) and MRA in our department. One hundred and forty-seven patients were vertiginous patients. We measured the displacement angle of the basilar artery with MRA, and examined the relationship between the findings from some neurological examinations and MRA findings in patients with vertigo and dizziness. One hundred and forty-seven patients with vertigo or dizziness were examined by MRI and MRA. They were diagnosed with MRI images in addition to several neurological examinations. MRA was not used for the diagnosis but rather for measuring the displacement angle of the basilar artery. Eighty-six cases with central vestibular disorders, 11 cases with vertebrobasilar insufficiency, and 26 cases with autonomic nerve disorders were recognized. In the cases of central vestibular disorders, the incidences of hyperlipidemia and hypotension were higher than the incidence of anemia. The average displacement angle of the basilar artery (n = 180) was 153.4 degrees +/- 39.4 degrees (mean +/- S.D.). MRA findings were classified into five categories. Ten patients were classified as category III, which represented unilateral partial vertebral artery stenosis. The detection rate for category III and IV abnormalities by neurological examination was higher than that for the other categories. MRI and MRA are important methods to examine patients with central nervous disorders. Distal vertebral artery stenosis may carry a higher risk of a stroke than brainstem infarction.

A Clinical Study of the Diagnosis of the Endolymphatic Hydrops Aspect of Ménière’s Disease

Hydrops of the endolymphatic system is the most striking pathologic finding in the inner ear in Meniere’s disease. It was discovered simultaneously by Yamakawa [1] and Hallpike and Cairns [2] in 1938 and has subsequently been confirmed by numerous investigations. In our study, the glycerol test, the electrocochleogram (ECochG) and the furosemide tests with caloric stimuli and/or centric & eccentric pendular rotation stimuli were administered to patients with Meniere’s disease. The purpose of the study was to diagnose endolymphatic hydrops in these patients in comparison with that in patients with sudden deafness without vertigo.

Pathohistological Study with Four Kinds of Stress Stimulations on Active Endolymphatic Hydrops in the Guinea Pig

Meniere’s disease is believed to show pathological features of endolymphatic hydrops [1, 2], but the etiology of this disease has not yet been ascertained. Many investigators [3], have attempted to create animal models with endolymphatic hydrops by obliterating the endolymphatic sac and duct. However, this method has been unable to adequately explain the development of Meniere’s disease because it uses simulated apparatus. On the other hand, Meniere’s disease is thought to develop as a result of stress to the inner ear mechanism although there have been no reports on endolymphatic hydrops induced by stress. We conducted a short-term experiment, creating active endolymphatic hydrops by stress load, to study the occurrence rate of endolymphatic hydrops. This was followed by a light-microscopic study on the changes in permeability of the cochlear lateral wall with horseradish peroxidase and a study of the dynamics of endolymphatic hydrops.

Clinical Study of Ternelin Therapy and Ternelin and Hydergine Therapy for Tinnitus.

Patients with tinnitus were treated with Ternelin® (tizanidine hydrochloride) alone or in combination with Hydergine® (dihydroergotoxine mesylate). The following results were obtained.1) When overall improvement was assessed at the end of the dosing period, 36% of the 136 patients who received Ternelin and Hydergine® (the combined therapy group) showed moderate or marked improvement, while 61.8% of the patients in this group showed slight, moderate or marked improvement. The combined therapy was rated as moderately or highly useful in 35.3% and slightly to highly useful in 61% of all cases.2) Of the 24 patients who received Ternelin alone (the solo therapy group), 25% showed moderate or marked improvement, and 66.7% showed slight, moderate or marked improvement. Solo therapy was rated as moderately or highly useful in 25% and slightly to highly useful in 66.7%.3) of the 153 patients who received combined therapy (including 17 patients who were only included in the safety assessment), 9 developed adverse reactions (3 cases of drowsiness, and one each of orthostatic syncope, hypotonia, dizziness, gastric pain, constipation and oral thirst). None of the patients given Ternelin® alone showed any adverse reactions.4) The percentage of cases showing marked or moderate improvement was higher in the combined therapy group than in the solo therapy group, although this difference was not significant. In the ombined therapy group, the reduction in tinnitus peaked 2 to 4 weeks afterr the start of treatment. In the solo therapy group, the number of patients responding to the drug increased gradually with time, and more time was needed to obtain maximal effects than that in the combined therapy group.

Electrocochleography of the Contralateral Ear in Patients with Unilateral Meniere's Disease.

It is well known that some patients with unilateral Menieres disease subsequently develop bilateral involvement. Since electrocochleography (ECochG) is useful in assessing endolymphatic hydrops, extratympanic ECochG was performed on both ears of 44 patients with unilateral Menieres disease from 1985 to 1992. We investigated the relationship between ECochG findings and the hearing level. The negative summating potential (SP)/action potential (AP) ratio of normal control subjects in response to 80 dBnHL clicks was 0.231±0.063 (n=40), so a negative SP/AP ratio of more than 0.36 (=mean±1.96SD) was regarded as a positive ECochG response.In 32 involved ears and 6 contralateral ears, the ECochG response was positive. The negative SP/AP ratio of the involved ears was larger than that of the contralateral ears in all cases. The negative SP/AP ratio showed a significant difference between the involved ears and the contralateral ears as well as between the involved ears and the ears of control subjects, but not between the contralateral ears and the control ears. The hearing level of the involved ears with a positive ECochG response was worse than that of the ears with normal ECochG findings. The hearing level of the involved ears was better when the contralateral ear was positive on ECochG than when it was not. The time from the first episode to the performance of ECochG was shorter when the contralateral ear was positive on ECochG than when it was not, but the difference was not significant. The largest negative SP/AP ratio in the contralateral ears was 0.48, which was not as large as that in the involved ears. It seems likely that patients with a positive ECochG response in the contralateral ear will develop bilateral Menieres disease, but we have not yet confirmed this clinically.In conclusion, the contralateral ear may show a positive ECochG response even in the early stage of unilateral Menieres disease.

Azelastine Hydrochloride Treatment of Allergic Rhinitis. Multi-Hospital Clinical Study in Nara Prefecture.

The effects of azelastine were investigated in 23 patients with perennial and 57 with seasonal allergic rhinitis seen in our institutions between October 1986 and April 1988. The antigen in seasonal allergic rhinitis was identified as Japanese cedar pollen in 45 patients and cocks footgrass in 12.1. In the rating general improvement of the response was classified as moderate or better in 47.8% of those with perennial rhinitis and as slight or better in 82.6%. The corresponding values for seasonal rhinitis were 57.9% and 84.2%. The combined ratings were 55.0% and 83.8%, respectively.2. Treatment reduced the following symptoms: sneezing, nasal secretions, nasal obstruction, disturbances in daily living, and volume of secretion.3. Japanese cedar pollinosis was treated in 25 patients in 1987 and in 20 in 1988. The general improvement ratings were 40.0% and 68.0% in 1987 and 75.0% and 95.0% in 1988. Considering that in 1988 the Japanese cedar pollen count was four times that in 1987 the difference in the general improvement rating between the two years may be due more to the duration of treatment than to the pollen count.4. Drowsiness as an adverse reaction was noted in 4 of the 80 patients, and treatment was discontinued in one.5. In general utility the drugs usefulness was rated as moderate or better in 47.8% of the perennial rhinitis patients and as slight or better in 78.3%. The corresponding values for the seasonal rhinitis patients were 57.9% and 84.2%, respectively. The general utility ratings for both types combined were 55.0% and 82.5%.

Analysis of tympanometry in hearing impaired school children.

Tympanometric and otoscopic evaluations were performed in 56 children with sensorineural hearing loss, aged 4 to 11 years.Type B tympanograms were found in 17.2% of the 4-to 6-year-old group, and 0% of the 7-to 11-year-old group.The children with type B tympanogram were re-examined in Nara Medical University, and otitis media with effusion (OME) was diagnosed in 4 (13.8%) of the 29 younger children (4-to 6-year-old).The incidence of OME in children with sensorineural hearing loss seemed to be almost the same as in healthy children. The incidence of OME was high in younger children.OME seemed to raise the hearing threshold in the younger group.

Clinical evaluation of Myonal in patients with tinnitus.

Myonal® was used to treat 36 patients with tinnitus.1. The rate of effectiveness was 47.2%.2. Myonale was effective in aged patients, patients with presbycusis, and patients with stiff shoulders.3. Tinnitus was reduced in most patients with improvement of stiff shoulders and the sense of fullness in the ears.4. There were no side effects.