This is a statistical analysis of 3349 patients who visited our clinic complaining of vertigo and dizziness 1977 to 1991. The number of patients has been increasing, especially patients over 65 years of age. A peripheral origin was noted in 29.4%, a central origin in 7.2%, systemic disease in 21.3%, and unknown in 42.1%. Vestibular dysfunction due to ototoxic drugs (KM.SM) and vertigo following head trauma were predominant in males, vertigo due to hypotension was in females. Vertigo due to hypotension was common in patients under 15 years of age, while many of those over 65 years of age had vestibular dysfunction due to ototoxic drugs (KM.SM) or vertigo due to hypertension. Half of the patients complained of vertigo and one third complained of dizziness. Vertigo with hearing loss was predominant in patients over 65 years of age. In 1990 and 1991, there were more patients over 65 years of age than in 1977-1978, and vertigo due to hypotension or hypertension was more common.
The nucleus of the optic tract (NOT) in the pretectum in both afoveate and foveate mammals has been considered to be the interface between the retina and premotor nuclei in the pathway conveying signals responsible for horizontal optokinetic nystagmus (OKN). Howevr, the parts of the retina and the kinds of retinal ganglion cells project which their fibers into the NOT are still not completely known. To clarify this pathway, we injected horseradish peroxidase conjugated with wheatgerm agglutinin into the NOT of the cats. In both retinae, labeled retinal ganglion cells were observed only above the horizontal meridian through the optic disc, and they were situated mainly in the temporal retina lateral to a vertical line through the disc. In both retinae, the highest concentration of labeled cells was the area centralis and the region adjacent to it. Most of the labeled cells were small cells, i.e., W cells. However, X-like cells and Y-like cells were also definitely labeled, suggesting that these cells pariticipate in OKN.
Temperature changes in the human middle ear were investigated during surgery. I examined four ears of subjects with facial nerve palsy and three ears of subjects with chronic otitis media. Microthermistors were positioned in the external ear canal, lateral semicircular canal, and attic. Following water irrigation (30°C and 20°C), I recorded the resistance of the thermistor by video-tape recorder and then converted the readings to temperature. The mean maximum temperature change in the lateral semicircular canal was -0.70°C at 30°C stimulation (58 seconds after irrigation) and -1.59°C at 20°C stimulation (62 seconds after irrigation). The degree of mastoid pneumatization seemed unrelated to the maximum temperature change in the lateral semicircular canal. I made a onedimensional mathematical model of thermal conduction and compared it with the measured data, but the model was incomplete.
Vestibular compensation in patients with bilateral vestibular dysfunction was examined with the use of static posturography (SPG) and kinetic posturography (KPG). SPG was recorded by a stabilometer during quiet stance and KPG was recorded by POLGON so that angular changes of the shoulder in the frontal plane were measured during stepping in the same position. In addition, we recorded movements of daily life. The subjects were 3 patients with bilateral vestibular loss. The values of SPG decreased gradually. However, abnormalities of KPG with eyes closed tended to persist, and the effect of vestibular training was transient. In regard to movements of daily life, the jumbling phenomenon during walking disappeared within 6 to 8 months, but jumbling with quick head motion persisted. Unsteadiness while standing on a sofa, or putting on socks while standing on one leg, or walking in a dark room persisted.
This is a case report of oblique periodic alternating nystagmus (PAN). This unusual nystagmus is provoked by intermittent vertebral artery compression (Powers' syndrome). Periodic alternating nystagmus (PAN) is rarely associated with oblique nystagmus. The nystagmus observed in this case seemed to consist of two superimposed types of nystgmus: horizontal PAN and downbeat nystag-mus. The mechanism of PAN is not known. However, lesions in the vestibulocerebellum or neighboring sites in the brainstem are known to have caused some cases of PAN. Downbeat nystagmus has also been produced by a lesion in the vestibulo-cerebellum. It was impossible to distinguish lesions in the vestibulocerebellum from those in the brainstem in this case. Nonetheless, the evidence, taken together, indicates that the cause of oblique PAN in this case could be lesions in the uvula and nodulus or in the related neural network in the brainstem.
We evaluated subjective complaints as a method of evaluation of the effects of treatment of vestibular vertigo (Gifu University Method). In the evaluation of subjective complaints of vertigo, the following should be considered; (1) effects of treatment of vertigo, (2) effects of treatment of disability in activities of daily life, and (3) the degree of patient satisfaction. We reexamined the classification of durations of definite spells of vertigo in our evaluation of the effects of treatment of subjective vertigo in 26 patients with Meniere's disease. We found the following classification useful: stage 1, no vertigo; stage 2, less than 19 minutes; stage 3, 20 minutes 6 hours; stage 4, more than 6 hours.
We report our assessment of objective findings as a method of evaluation of the effect of treatment of vestibular vertigo (Gifu University method). The following should be investigated, (1) effect of treatment on vertigo, (2) effect of treatment on damage to the inner ear, (3) effect of treatment on recurrent attacks of vertigo, and (4) objective effect of treatment on improvement of activities of daily living. We reviewed the period of evaluation after treatment of recurrent attacks of vertigo, and formulated a numeric equation for the number of cluster attacks. The effect of treatment on recurrent attacks of vertigo was evaluated by comparing the number of attacks a month after the start of treatment with the number before treatment. Twenty-six patients with Meniere's disease were questioned about the number of attacks of vertigo and the effect of treatment one month, 6 months, 12 months and 24 months after the start of treatment. The results indicated improvement after one month of treatment in 11 patients (42%), after 6 months in 16 patients (62%), and after 12 months in 19 patients (73%). After 24 months of treatment, the figures were unchanged. A period of at least 12 months is necessary to evaluate the effect of treatment on recurrent attacks of vertigo. In patients with cluster attacks of vertigo, the effect of treatment must be evaluated differently. The duration of a cluster and the number of attacks in a cluster must be compared before and after treatment.
The origin of nystagmus, and the neurological symptoms and signs in 5 patients with Wallenberg's syndrome were related to the site and extension of lesions revealed by MRI. The relationship between nystagmus and a lesion in the neural structure, especially in the vestibular nucleus, was studied. 1. Pure rotatory nystagmus was observed in 3 of the 5 patients, rotatory nystagmus with dissociated vertical movements like a see-saw in one, and no nystagmus in one. 2. Nystagmus towards the side of the lesion was observed in one patient and nystagmus towards the contralateral side in 3. 3. MRI did not reveal any lesions at the level of the lateral vestibular nucleus in any of the patients. 4. Two patients, who had lesions in the medial and or inferior vestibular nucleus, did not complain of vertigo. On the contrary, 3, who had no lesions in the vestibular nuclei, complained of vertigo or dizziness. Therefore, it was supposed that a lesion adjacent to the vestibular nuclei associated with preservation of the vestibular nuclei might cause vertigo. 5. Both skew deviation of the eyes and head tilt phenomenon were observed only in patients with no preservation of the medial and or inferior vestibular nucleus. 6. Recording of eye movements with a CCD camera was very helpful in the analysis of nystagmus and in the follow-up studies of these patients.
Cyochrome oxidase (CO) activity of primary vestibular afferent neurons in Scarpa's ganglion of the squirrel monkey was demonstrated histochemically under normal and experimental conditions. The right vestibular nerve of adult squirrel monkeys was sectioned between Scarpa's ganglion and the brainstem under general anesthesia. The left side was used as a normal control. Following a survival period of seven months, neurons in Scarpa's ganglion on both sides were examined. In normal sides, a negative correlation was observed between the sizes of the neurons and their CO activities. The vestibular neurons in the transected side survived, but their cell sizes and CO activities were reduced in comparison with those on the control side.
We compared the effectiveness of 2 different therapies in elderly patients with benign paroxysmal positional vertigo. Eighteen patients were treated with an anti-vertigo drug and 18 with vestibular training (VT) and the same drug. They were classified into Group "B" and "VT + B", respectively. The background factors, such as age, severity in symptoms, degree of disturbance in examinations, et, were similar in the 2 groups. Vertigo, dizziness, unsteadiness in Mann's test and positional nystagmus improved significantly more in Group "VT+B" than in Group "B". The global judgment in each group revealed that both marked and moderate improvement was significantly higher in Group "VT+B" than in Group "B" (P<0.01). It was concluded that vestibular training might be useful to improve symptoms and signs in benign paroxysmal positional vertigo even in aged patients.
The morphology of five kinds of horizontal vestibulo-ocular refrex-related brainstem neurons (Vestibular type I neuron, Abducens motoneuron, Abducens internuclear neuron, Reticular burst neuron, Omnipause neuron) in cats was investigated by intracellular staining with horseradish peroxidase (HRP) and threedimensional reconstruction of the cell bodies. Each neuron in and around the abducens nucleus was penetrated by glass micropipette for recording and identifying by their characteristic firing pattern during nystagmus and by their pattern of response to stimulation of the vestibular nerves. HRP was injected into the cell bodies or axons of these electro-physiologically identified neurons. After appropriate tissue preparation, cell body and axonal reconstructions were performed with the aid of a camera lucida equipped microscope. In this study 17 cell bodies were stained and reconstructed perfectly. The morphological characteristics, for example the diameter of the cell bodies, the number of primary dendrites and terminal dendrites, etc. in each neuron were compared with the previous descriptions done mainly by the Golgi method.
We carried out a questionnaire. survey on orthostatic dysregulation (abbreviated OD) in 63 young female subjects aged 18-19 years. Ten of them were judged to have confirmed OD, 8 had suspected OD, and the remaining 45 were regarded as normal. Schellong test results showed some difference in three items between the confirmed OD group and normal subjects, but the positive rate of the Schellong test in itself was not significantly different among these three groups. It was our impression that a more detailed analysis of this test is needed to increase its diagnostic validity in determining OD. The Cornell Medical Index-Health Questionnaire (abbreviated CMI) which was modified for the Japanese population with emotional disturbances by Fukamachi was given to these subjects to obtain information about their underlying psychological and emotional status. According to Fukamachi's classification Type III or IV patterns, suggestive of suspicious (III) or probable (IV) neurosis were found in 5 (11.1%) of the normal subjects, in 3 (30.3%) of the subjects with confirmed OD, and in 4 (50.0%) of those with suspected OD. These data suggest a correlation between OD and emotional and/or psychogenic disturbances. Subjects with OD and patients with vertigo or dizziness who visited our clinic were noted to have similar results on CMI. This does not, however, necessarily mean that some subjects with OD are abnormal or sick, since the CMI itself is intended only as an adjunct to, and not as a substitute for, medical interviews and physical examinations.
We developed a new swimming test for evaluating the degree of equilibrium dysfunction of rats with hemilateral vestibular disorder. The behavior of swimming rats in a water bath was observed for 60 sec. When a rat sank in the water, rotating about its longitudinal axis, the observation was stopped and the time was calculated. When a rat with both ears above the water, its behavior was assessed as normal swimming; when a rat swam with one ear under water, it was considered to be abnormal swimming. The swimming score was calculated by the following formula: [the duration (seconds) of normal swimming] + 1/2x [the duration (seconds) of abnormal swimming]. We think that this new swimming test will be useful in basic pharmacological research on therapy of balance disorders.
Vertigo attacks are believed to be caused by many potassium ions from the endolymph entering the perilymphatic space upon rupture of the membraneous labyrinth due to hydrops in Meniere's disease (Schuknecht, 1972). At the beginning of an attack, irritative nystagmus, or nystagmus directed towards the ill side, was observed in 3 of 5 patients with Meniere's disease. Worsened hearing, increse of body sway during standing with eyes closed, increase of deviation towards the ill side in writing test with eyes covered, positional nystagmus of the direction changing type towards the upper ear and changing of DP to the intact ear side from DP to the ill side were observed in the pendular rotation test just before an attack of vertigo in one patient with Meniere's disease. Those findings were assumed to have been induced by hypofunction of the labyrinth due to acute progression of hydrops in Meniere's disease.
A new apparatus capable of recording head and eye movements was devised to examine the vestibulo-ocular system. Horizontal and vertical head movements were recorded with a sensor of terrestrial mgnetism. Eye movenments were recorded by an electronystagmographic technique. The transmitted data were stored on a floppy disc and analyzed with a microcomputer in a specially designed program. 1. The apparatus was useful as a tool for recording spontaneous and gaze nystagmus and pursuit and saccadic eye movements in patients with labyrinthine and central disturbances. 2. Transfer function (gain and phase) of the vestibulo-ocular system was calculated with head and eye movements obtained from pseudo-random head oscillation in the dark. In normal subjects, gain with head movements as input signal and eye movements as output signal indicated a frequency-dependent gain enhancement;the phase difference between head eye movements was 180°. 3. The vestibulo-ocular reflex (VOR) induced by the right and left labyrinth were examined with velocity recording of head and eye movements induced by quick head movements to the right and left at intervals of 1 second in the dark. Patients with unilaterl labyrinthine disturbance showed a low amplitude response in head movements toward the affected labyrinth. 4. The integration mechanism in the pursuit system was examined from the velocity recording of eye movements during vertical head oscillation with fixation on a visual target. A patient with primary position upbeat nystagmus caused by nutritional deficiency encephalopathy showed a disturbance of the up neural integrator from velocity signal to position signal in the visual vestibular oculomotor system. The apparatus was usuful for the examination of the vestibulo-ocular system of patients with vertigo and equilibrium disturbances.
We investigated the course of Meniere's disease by questionnaires sent to 94 patients in June 1992. Sixty-seven of them sent back information as to whether they still had attacks of vertigo and whether they had been treated since they visited our clinic between 1981 and 1986. On the basis of their responses, they were divided into 2 groups: those who had not been treated or had been treated only when they had attacks of vertigo (natural course group) and those who had been treated for a certain period (treated group). We judged that they were cured of vertigo if the period without attacks was over 2 years and longer than their maximum attack-free intervals. The percentage of cures was similar in the 2 groups, but the time between the first and the last attack of vertigo was longer in the natural course group than in the treated group.
Patients who suffer from dizziness have various sensations, such as a sense of rotation or unsteadiness. To understand these differences, we investigated the sensation of dizziness during caloric testing and correlated the direction of rotatory sensation with nystagmus in 51 healthy adults who had no vestibular disorders. During caloric testing, 79.8% reported a sensation of rotation, 13.7% felt unsteady and only 6.5% had neither sensation. Of those with a sensation of rotation, 79.1% had nystagmus to the direction of sensation and 20.9% had nystagmus to the opposite side. During caloric testing with eyes-open in the light, most of the subjects felt as though the outside world were rotating, while in tests with eyes-open in the dark or with eyes-closed, most subjects felt themselves rotating. Caloric tests evoked quick and slow phases of nystagmus. It has been understood that the image of the outside world is caugnt by the fovea in the slow phase. If the quick phase of nystagmus is induced to the left, when the eye moves from right to left, the image of the surroundings seems to move from left to right. It was concluded that the direction of the sense of rotation in dizziness corresponds to the direction of nystagmus.
The various influences on posture of visual and somatosensory conditions were analyzed in 15 normal subjects with the use of the EquiTest and optokinetic stimulation. Two types of somatosensory input were used: a static support surface and a moving surface coordinated with the anterior-posterior (A-P) sway of the subject. Four types of visual input were applied in each somatosensory condition: (1) eyes open, (2) eyes closed, (3) movement of visual surroundings coordinated with A-P sway, (4) horizontal optokinetic stimulation. On the static support surface, the center of gravity (COG) was very stable with eyes open and with optokinetic stimulation. The COG was less stable when the eyes closed, and the least stable when the visual surroundings were moving. The FFT in the A-P direction under static somatosensory conditions showed characteristic changes when the visual surroundings were moving: a significant increase of power in the frequency range below 0.25 Hz, a decrease between 0.25 and 0.5 Hz. Although no significant change in lateral direction was observed, the power under optokinetic stimulation seemed to be 10% greater in the range of 0.25-0.5 Hz than it was under the three other visual conditions. On a moving support surface, however, COG stability was severely disturbed under all visual conditions except with the eyes open. Furthermore, FFT showed no differences when the subject was standing on a moving support surface. We concluded that sensory conflict caused by moving visual surroundings affects postural stability more than do the other visual conditions tested in our experiment. However, sensory conflict caused by the reduction of somatosensory information results in more severe instability than that caused by any of the visual conditions. These findings confirm the importance of sensory information for postural stability in humans.
We performed neurootological examinations on 20 patients with various collagen diseases who had dysequilibrium: 12 patients with systemic lupus erythematosus (SLE), 3 patients with Rheumatoid arthritis, 3 patients with Takayasu's disease, 1 patient with Cogan's syndrome, and 1 patient with polyarteritis nodosa. The mechanism of dysequilibrium in those cases was discussed. In the patient with Cogan's syndrome, inner ear damage, manifested by perceptive deafness and horizontal nystagmus, had developed together with arthritis and keratitis. These symptoms were postulated to be due to an autoimmune reaction against type II collagen which composes the matrix of the cartilage in joints, cornea and inner ear. In one of the patients with Takayasu's disease, down beat nystagmus and subclavian steal syndrome were noted, so dysequeilibrium was considered to be due to vertebrobasilar insufficiency. Of the 5 patients with SLE and central vestibular lesions, 4 had disturbance of pursuit, saccade and optkinetic nystagmus, but without no focal neurological signs. Computed tomography scans showed cerebellar atrophy in 2 patients with SLE, but none had intracranial hemorrhage or infarction, although it is generally thought that neurological symptoms in SLE are produced by small intracranial hemorrhages or infarctions. Therefore, some other mechanism must be present. Probably immune complex deposits adhere to blood vessels walls and cause defects through which cytotoxin flows to produce wide areas of cerebral damage.
We present here a 25-year-old flier who developed recurrent acoustico-equilibrium disorders following recovery from acute acoustic trauma of the left ear suffered during a military air force exercise. Several recent reports have described vertigo associated with acoustic trauma as probably due to endolymphatic hydrops (ELH) caused by trauma. However, detailed studies of these reports fail to reveal definite evidence of ELH, and the incidence of ELH among patients whose vertigo was related to acoustic trauma seemed to be lower than the incidence reported in the literature. The clinical data of the patient presented here, inciuding ECochG and glycerol test are compatible with bilateral ELH, although his symptoms were in the left ear only. Since military personnel inevitably experience not only noise trauma but also various physiological and psychological stresses, factors such as genetic traits may play a role in the development of ELH. Therefore, we believe that ELH had been present before the onset of his inner ear symptoms and that the acoustic trauma might have changed the inner ear condition from nonsymptomatic to symptomatic ELH. Two patients with histological evidence of temporal bone pathology, as well as the results of basic studies reported previously, support our concept regarding acute acoustic trauma and recurrent acoustico-equilibrium disorders.