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H Shojaku

Publications and source records attributed to H Shojaku.

36 records · Page 2Linked to original sources

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↗

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↗

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↗

Facial nerve palsy as a complication of parotid gland surgery and its prevention.

The incidence of postoperative facial palsy in 73 patients who had under-gone surgery for parotid gland tumor is reported. Slight facial palsy occurred in 9 (14%) of 66 benign tumors but recovered completely within 3 months following surgery. However, in 7 patients with malignant tumors, 3 (43%) developed permanent palsy and 1 (14%) temporary palsy. The incidence of benign tumors depends on the tumor size and localization. However, the incidence decreased considerably in the last 6 years compared to the first 6 years. This is considered to be due to routine use of computed tomography with sialography and microsurgery during parotidectomy.

Adenocarcinoma↗

Nasal septal neurinoma.

A case of nasal septal neurinoma is presented. The patient was a 71-year-old male who complained of nasal obstruction and epistaxis. Results of the physical examination showed a giant mass filling the nasal cavity and the nasopharynx. A biopsy taken from its tissue surface showed histological features of neurofibroma. The lesion was completely resected with the patient under general anesthesia. The tumor completely occupied the right nasal cavity and the nasopharynx, partially penetrated the nasal septum and extended to the left nasal cavity. After the operation, the final pathological diagnosis was not neurofibroma but neurinoma in which Antoni type A and type B cells were mixed. The postoperative course was uneventful, and no recurrence has been observed to date.

Aged↗

Secondary vestibular cholinergic projection to the cerebellum of rabbit and rat as revealed by choline acetyltransferase immunohistochemistry, retrograde and orthograde tracers.

Previously we have shown that four regions of the cerebellum, the uvula-nodulus, flocculus, ventral paraflocculus, and anterior lobe 1, receive extensive, but not exclusive, cholinergic mossy fiber projections. In the present experiment we have studied the origin of three of these projections in the rat and rabbit (uvula-nodulus, flocculus, ventral paraflocculus), using choline acetyltransferase (ChAT) immunohistochemistry in combination with a double label, retrogradely transported horseradish peroxidase (HRP). We have demonstrated that in both the rat and rabbit the caudal medial vestibular nucleus (MVN) and to a lesser extent the nucleus prepositus hypoglossus (NPH) contain ChAT-positive neurons. Neurons of the caudal MVN are double-labeled following HRP injections into the uvula-nodulus. HRP injections into the uvula-nodulus also labeled less than 5% of the neurons in the cholinergic vestibular efferent complex. Fewer ChAT-positive neurons in the MVN and some ChAT-positive neurons in the NPH are double-labeled following HRP injections into the flocculus. Almost no ChAT-positive neurons in the MVN and some ChAT-positive neurons in the NPH are double-labeled following HRP injections into the ventral paraflocculus. Injections of Phaseolus leucoagglutinin (PHA-L) into the caudal MVN of both the rat and rabbit demonstrated projection patterns to the uvula-nodulus and flocculus that were qualitatively similar to those observed using ChAT immunohistochemistry. We conclude that the cholinergic mossy fiber pathway to the cerebellum in general and the uvula-nodulus in particular is likely to mediate secondary vestibular information related to postural adjustments.

Animals↗

Vestibularly induced slow oscillations in climbing fiber responses of Purkinje cells in the cerebellar nodulus of the rabbit.

In this report we describe an interesting form of plasticity in climbing fiber responses evoked in Purkinje cells of the rabbit cerebellum by periodic vestibular stimulation. The cerebellar nodulus receives a vestibular as well as a visual climbing fiber afferent input from the contralateral inferior olive. The vestibular input to the inferior olive originates from the ipsilateral medial and descending vestibular nuclei and terminates within the beta-nucleus. This projection to the beta-nucleus from secondary vestibular neurons is GABAergic. This means that vestibularly evoked activity of neurons in the beta-nucleus is controlled by modulation of an inhibitory input, rather than by modification of an excitatory input. We have recorded the climbing fiber responses of single Purkinje cells in the uvula-nodulus (lobules 9c, 9d and 10) of rabbits and we have characterized the climbing fiber response of each Purkinje cell from which we recorded by testing its sensitivity to otolithic stimulation, semicircular canal stimulation and optokinetic stimulation. Vestibularly evoked climbing fiber responses recorded from the left nodulus were stationary. They were repeatedly evoked, for tens of minutes, by sinusoidally rotating the rabbit about the longitudinal axis onto its left side (Fig. 1B). When the vestibular stimulus was stopped the discharge of these climbing fiber responses returned to non-periodic spontaneous levels. However, the vestibularly evoked climbing fiber discharge of approximately 5% of Purkinje cells was not stationary.(ABSTRACT TRUNCATED AT 250 WORDS)

Action Potentials↗

Cerebral autoregulation in patients with orthostatic hypotension.

The present study was conducted to determine the relationship between autonomic nervous function and cerebral autoregulation in 17 patients with vertigo or dizziness. Autonomic nervous function was examined by measuring systolic blood pressure response and dynamic electrocardiogram R-peak to R-peak response upon standing up. Regional cerebral autoregulation was examined by comparing cerebral blood flow in both supine and standing positions with single photon emission computed tomography. Moreover, the relationship of each of these three measures to postural provocation of symptoms was studied. The findings indicated that autonomic nervous dysfunction does not influence cerebral autoregulation, but autonomic nervous dysfunction was related to postural provocation of symptoms. This might indicate that impaired autoregulation in the brain stem or the peripheral vestibule, which could not be detected by the single photon emission computed tomography, played a role in inducing vertigo or dizziness in patients with orthostatic hypotension.

Adult↗

Influence of vestibular and visual climbing fiber signals on Purkinje cell discharge in the cerebellar nodulus of the rabbit.

Extracellular recordings of the climbing fiber responses (CFRs) of single Purkinje cells were made in the cerebellar nodulus and ventral uvula of anesthetized pigmented rabbits. Natural vestibular and optokinetic stimuli were used to evoke responses from these Purkinje cells. Using a null response technique we sorted vestibularly-evoked CFRs into two canal-related categories. CFRs were related to either the ipsilateral anterior and contralateral posterior semicircular canal (iAC+cPC) or to the ipsilateral posterior and contralateral anterior semicircular canal (iPC+cAC). Both canal-related CFRs also responded to downward optokinetic stimulation.

Acceleration↗

Vestibular and visual signals in the ventral paraflocculus of the cerebellum in rabbits.

Extracellular microelectrode recordings from single cerebellar neurons were made in the ventral paraflocculus of anesthetized, paralyzed pigmented rabbits during vestibular and visual stimulation. The discharge of 6 out of 207 neurons was modulated during vestibular or visual stimulation. The activity of 5 neurons was modulated during vertical vestibular stimulation. The discharge of only one neuron was modulated exclusively during vertical optokinetic stimulation. The information from both the vestibular and visual systems which is received by the ventral paraflocculus appears to differ from that which is received by the flocculus in rabbits.

Action Potentials↗

The furosemide VOR test for Menière's disease. A preliminary report.

In order to easily detect endolymphatic hydrops and to avoid the side effects, we applied a furosemide VOR test in 24 patients with unilateral Meniere's disease, 6 patients with delayed endolymphatic hydrops, and 2 patients with labyrinthine syphilis. Immediately preceding an i.v. injection of 20 mg furosemide, and then 30, 60, 90 min after the administration, the VOR test was repeatedly performed. The slow-phase velocity in the VOR test was measured during harmonic sinusoidal rotation with eyes closed. Increased or decreased VOR-DP% beyond the normal range (10%) was referred to as positive. In 13 out of 24 cases (54%) with Menieres's disease, positive results were observed. Moreover, 4 out of 6 (67%) with delayed endolymphatic hydrops, one case out of 2 with labyrinthine syphilis were also positive in the furosemide VOR test. From these clinical investigations, we have concluded that the furosemide VOR test appeared to be another type of clinical test for the detection of vestibular endolymphatic hydrops.

Adult↗

Epidemiological studies on benign paroxysmal positional vertigo in Japan.

In 1980, the Research Committee of Peripheral Vestibular Disorders in Japan, which is supported by the Ministry of Health and Welfare, was founded by 24 members, from several districts in Japan. The Committee's first task was to draft the diagnostic criteria for several peripheral vestibular disorders, such as benign paroxysmal positional vertigo (BPPV), and vestibular neuronitis. For the national epidemiological survey, they then collected the data on 101 cases of BPPV out of some 783 vestibular disorder patients. In addition, data on 103 patients of BPPV out of 559 vestibular disorder patients were also collected from the Neuro-otological Clinic of the Toyama Medical and Pharmaceutical University Hospital. From these epidemiological surveys, the incidence of BPPV in Japan was estimated at 10.7 per 100,000 population, while that of BPPV in Toyama was estimated at 17.3 per 100,000 population. The ratio of BPPV was higher in female than male patients in both surveys. The age at the onset of BPPV peaked in the fourth decade in both males and females. Compared with the other epidemiological features of Meniere's disease and sudden deafness with vertigo in the same surveys, it appeared that the characteristic features of BPPV are epidemiologically similar to those of Meniere's disease, but different from those of sudden deafness.

Female↗

Topographical distribution of Purkinje cells in the uvula and the nodulus projecting to the vestibular nuclei in cats.

The localization of the Purkinje cells in the uvula and nodulus projecting to the vestibular nuclei and the prepositus hypoglossal nucleus (PH) was studied by means of retrograde axonal transport of horseradish peroxidase in cats. Findings indicate a zonal organization in the uvula and nodulus projecting to the vestibular nuclei as follows; the Purkinje cells located in the medial half of the uvula except for the area along the posterolateral fissure project to the middle part of the inferior vestibular nucleus (IV) (middle IV zone); those in the lateral half of the uvula other than the laterocaudal part project to the caudal part of the IV (caudal IV zone); those in the mediorostral part of the nodulus and the middle part of the nodulus project to the middle part of the medial vestibular nucleus (MV) (middle MV zone); those in the lateral part of the nodulus project to the caudal part of the MV (caudal MV zone); those in the medial part of the uvula and nodulus along the posterolateral fissure project to the dorsal peripheral part of the superior vestibular nucleus (SV) (SV zone). There is no specific projection zone in the uvula and nodulus projecting to the lateral vestibular nucleus, the ventral peripheral and the central part of the SV, the rostral part of the MV, the rostral part and the caudal pole of the IV, the caudal one-third of the group f, the group x and the PH.

Animals↗

Neuronal pathway from floccular caudal zone contributing to vertical eye movements in cats--role of group y nucleus of vestibular nuclei.

In ketamine-anesthetized cats, electric microstimulation of the group y nucleus of the vestibular nuclei evoked a slow and smooth upward eye movement. Destruction of the group y nucleus eliminated a slow and smooth downward eye movement evoked by stimulation of the caudal zone of the flocculus. These data support the interpretation that Purkinje cell activity in the caudal zone of the flocculus can evoke vertical eye movements by inhibiting the activity of neurons of the group y nucleus.

Animals↗

MR sialographic evaluation of sialectasia of Stensen's duct: comparison with X-ray sialography and ultrasonography.

We describe a patient with unilateral sialectasia of Stensen's duct. X-ray sialography, MR sialography, and ultrasonography showed multiple stenoses and rosary dilatation of Stensen's duct during stimulation of the parotid gland. Before stimulation, Stensen's duct showed focal dilatation as indicated by MR sialography and ultrasonography. The patient also had ipsilateral masseter hypertrophy (BMH), which may be a cause of sialectasia.

Adult↗

Use of MR angiography in a pregnant patient with thalamic AVM.

A 32-year-old pregnant woman at 29 gestational weeks suffered from the acute onset of severe headache. Brain CT, MRI, and MR angiography (MRA) showed intraventricular and thalamic hemorrhage, ruptured from a thalamic AVM. Based on these findings, conservative treatment was continued until delivery. After cesarean delivery at 34 gestational weeks, conventional cerebral angiography was performed, followed later by gamma-knife therapy. In pregnant patients with suspected cerebrovascular disorders, MRI and MRA should be the first of choice method to evaluate information on the diseased vessels and associated lesions since there is no radiation risk or side effects of contrast medium.

Adult↗

Malignant gastrointestinal stromal tumor of the small intestine: radiologic-pathologic correlation.

Neoplasms of the small intestine are very rare. Gastrointestinal stromal tumors (GISTs) are one of the new undifferentiated stromal tumors of the gastrointestinal tract diagnosed by immunohistochemistry. We present a case of a malignant GIST arising from the small intestine and report the radiologic characteristics of the tumor and pathological correlation. CT showed a very large, enhancing mass with extensive central necrosis located on the mesenteric side of the jejunum. A perforation into the jejunal lumen was observed by upper GI series. MRI showed a very large tumor which was hypointense on T2-weighted images. Ultrasound revealed a mixed solid and cystic mass. Grossly, the tumor was solid peripherally with extensive central necrosis. Microscopically, it consisted of spindle and epithelioid cells. Immunohistochemically, the cells stained positive for CD34, which is diagnostic of GIST.

Antigens, CD34↗