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Aim/objectives: A typical vestibular stimulated myogenic potential (VEMP) response depends on suitable sound transfer from the middle ear to inner ear. This transfer is degraded at various degrees in otitis media with effusion (OME). In cases where the effusion is reduced by treating the OME, response to VEMP test can be obtained Backgrounds: In this study we aimed to compare preoperative and postoperative VEMP values of children who were applied ventilation tube for OME and to compare these values and VEMP values of healthy children. Materials and methods: Forty healthy and 40 patients with OME aged between 4 and 16 years were used for the study. VEMP test was performed before and after the surgery. Results: Significant decrease was seen in p13 and n23 values of patient group (p < .05). Statistically significant increase was seen in postoperative amplitudes of patient group (p < .05). Conclusions: Increased VEMP responses in children with OME have shown that dysfunction of middle ear caused vestibular dysfunction. We think that VEMP test can be used to follow up children with OME as a test for showing improvement. Significance: The VEMP test can be used a diagnostic and prognostic test in the diagnosis and follow-up of children with OME.

To determine and interpret the range of normal deviation of the bucket test in healthy subjects Subjects and methods: Study design: Cross-sectional study in a secondary care center.subjects ≥18 years old with no otologic or neurologic symptoms and normal complete neuro-otological examination. The subjective visual vertical was evaluated binocularly using the bucket test. Five measurements were made on the clockwise direction and five on the counterclockwise direction. The examiner selected the starting point, the patient then manipulated the bucket and it stopped when the volunteer considered the line reached the vertical position.Fifty healthy volunteers were included, 16 (32%) were men, and 34 (68%) women with a mean age of 34 years. The mean value found clockwise was 1.93° ± 2.26° and counterclockwise sense was of 0.86° ± 2.44°. Mean normal values ranged from 1.4° ± 1.9°.The bucket test is easy and quick to perform; we recommend to use a range of -1.0° to +3.0° as normal values in the healthy population.

It is suggested that the different results of rotational (video head impulse - vHIT) and caloric tests in patients with Ménière's disease (MD) may be a consequence of the physical enlargement of the membranous duct in the hydropic labyrinths in MD, causing a reduced response to caloric stimulation.There have been reports that the results of two tests of semicircular canal function, the caloric response and the responses to vHIT do not agree. This retrospective study at a tertiary referral hospital examined this disagreement.This study reviewed the data of 22 patients who met the AAO-HNS criteria for MD and who had both caloric and vHIT testing.There was a clear dissociation: patients with MD had a small or absent response to caloric stimulation of their affected ear, whilst their response to vHIT was in the normal range.The accepted Gentine model of the mechanism of caloric stimulation could account for this dissociation: the increased diameter of the semicircular duct in hydropic labyrinths resulting in endolymph circulation within the duct itself and so a smaller thermally induced pressure across the cupula. The increased duct diameter will have little effect on responses to rotation.

The everyday act of rising from a chair is known to require the combined angular control of a number of the body's joints, especially those within the pitch plane. Precisely how this control is exerted, however, remains controversial. The aim of this study was to obtain a better understanding of the contribution made by the vestibular apparatus to postural control of the body and head when an individual rises from a chair.A total of 24 healthy controls and 38 patients with varying degrees of vestibular dysfunction were examined. Electromagnetic motion sensors were used to analyze the angular control of the head and body as subjects rose from a chair with their eyes open or closed.We found that unilateral vestibular dysfunction caused fixation of the head with respect to the body, resulting in a loss of spatial stability of the head which was not compensated for by visual input. Visual input did appear to compensate for bilateral vestibular loss, enabling patients with bilateral vestibular apparatus impairment or central disorders to fix the position of their head in space.The act of rising from a chair is normally controlled by vestibular and proprioceptive input; the head is aligned according to the gravitational reference so as to obtain stable visual information. In patients with unilateral vestibular hypofunction, posture is still controlled by these two inputs, although the ability to align the head is diminished. In patients with bilateral vestibular hypofunction or a central disorder, head alignment is maintained using visual input, although it may not be the sole or predominant stabilizing force.

The square drawing test (SDT) devised by Sekitani (1975), which is a modification of Fukuda's vertical writing test, was performed to evaluate vestibular dysfunction in 15 patients with vestibular neuronitis followed up for a long period. In particular, two parameters (distance and total length) were analyzed in the present study. Distance was analyzed by dividing the 15 cases into 3 groups. The largest group showed a tendency to shorten at an early stage. Total length was examined by dividing the 15 cases into 3 groups. The largest group showed a tendency towards macrographism at an early stage. It was found that as the degree of caloric responses recovered, the range of distance and total length decreased. Considering the correlation between parameters of the SDT (distance and total length) and caloric responses we concluded that the SDT is a feasible method to evaluate and follow up patients with vestibular dysfunction.

Vestibular function testing was performed regularly on patients who were administered streptomycin, kanamycin, or enviomycin, and vestibular damage was detected at an early stage, and quantitatively. We investigated the point in time at which the therapy should be discontinued. Subjects consisted of 204 cases of tuberculosis treated with streptomycin, kanamycin, enviomycin. They were admitted to the hospital between December 1984 and August 1989. Twenty-eight cases of vestibular dysfunction due to streptomycin, kanamycin, and enviomycin could easily be detected at an early stage by performing Meyer zum Gottesberge's head-shaking test for the evaluation of jumbling, together with Romberg's test and the stepping test. All cases who had vestibular dysfunction completely recovered because of early detection. In addition, 7 cases recovered afterwards from temporary vestibular damage shown only in Meyer zum Gottesberge's head-shaking test (abnormality of vestibulo-ocular reflex was only detected and vestibulo-spinal reflex remained intact), despite continuation of streptomycin injection. When the results of the head-shaking test are less than 50% and when a sway and/or rotation in the stepping test occurs, the injections should be discontinued.

Symptomatic high frequency/acceleration vestibular loss is a distinct clinical entity that can be missed on conventional ENG with caloric testing. Under certain circumstances, symptomatic patients with a high frequency/acceleration vestibular loss should undergo an MSSC study for confirmation, if required.To document that normal electronystagmography (ENG) with conventional bithermal caloric testing is inadequate for diagnosing clinically significant high frequency/acceleration vestibular loss.Patients with clinical symptoms and signs of persistent peripheral vestibular dysfunction despite normal conventional bithermal caloric testing on ENG underwent high frequency/acceleration horizontal magnetic scleral search coil (MSSC) eye movement studies. The clinical findings and results from audiometric tests, conventional ENG with bithermal caloric tests and MSSC tests were reviewed.Eleven patients were identified as having an abnormal MSSC study, indicating a high frequency/acceleration vestibular loss consistent with their clinical history despite normal or equivocal bithermal caloric responses on conventional ENG. Although valuable, ENG caloric testing evaluates lateral semicircular canal function and should be considered a non-physiological test primarily of low frequency vestibular function. High frequency/acceleration head thrust testing clinically detected a "high frequency/acceleration vestibular loss" in 8/11(72.7%) cases.

We describe an attempt to model unilateral vestibular dysfunction in normal man by inducing vestibular asymmetry with exposure to long-term, unidirectional, visual-vestibular conflict. Subjects were exposed to pseudo-random (0.13, 0.2, 0.25, 0.3Hz; 77 degrees/s peak) oscillation in Yaw for 30 min whilst viewing a surrounding, whole field optokinetic drum which rotated with them when they were rotating rightwards and remained earth stationary when they rotated leftwards. Adaptation to this stimulus was assessed by combined tests of "goal-directed" vestibular-ocular reflex (VOR) and vestibular memory contingent saccades (VMCS) in 5 subjects and in a further 4 subjects by combined tests of perception of reorientation (a "navigation" task) and sinusoidal VOR at 0.1 and 0.32 Hz. The exposure induced a reduction in the gain of the VMCS and an underestimation of perceived amplitude of displacement when subjects were turned rightwards. VOR gain for rightwards movement was reduced more markedly at 0.1 Hz. No change was found in the goal-directed VOR gain. Thirty minutes after adaptation, the asymmetry of the VOR gain remained at 0.1 Hz, but vestibular perception recovered to normal. Asymmetrical adaptation can be achieved with short exposures and is more marked for low frequency stimuli. Modification reflex of vestibular functions endures longer than of perception of reorientation.

Unilateral vestibular hypofunction (UVH) is a common vestibular dysfunction. Its influence upon the vestibulospinal reflex (VSR) is studied by posturography. The postural sway is disturbed when the VSR is disregulated because of the UVH. The degree of disturbance depends on the effectivity of the central compensation. Our results indicate that these adaptive mechanisms become less effective with advancing age. The importance of ocular fixation as a compensatory mechanism is also obvious. The comparison between posturographic recordings made with eyes open and those made with eyes closed, shows that, in elderly people, more abnormal posturographic recordings are found with eyes closed. Accordingly, with regard to the problem of falling in the elderly, the function of the vestibular system must be assessed and especially its influence upon the standing posture. The combination of classical vestibular and posturographic results affords this indispensable information.

The symptoms of postural instability and dizziness associated with decompression sickness could be ascribed to either damage of the vestibular apparatus or to central nervous system damage. However, a histological study of monkeys exposed to decompression reveals that these symptoms primarily result from damage to the vestibular apparatus (unless there are accompanying central deficits). Furthermore, the damage is of a type that causes new bone growth to occlude the otic fluid spaces of the semicircular canals. In some instances, there is sufficient bone growth to render the cristae ampullares as non-functional end organs. Such diminished vestibular function would present a serious threat to the diver.

During recent decades, vestibular research has emphasized that it is important to consider vestibular reflexes a part of the integrated balance system function. Vestibular diagnosis must be based on a system approach to vestibular dysfunction. The development of new balance system examination methods is based on computerization of the analysis of transfer functions. Using these methods, system dysfunction is more easily understood and a new universe of vestibular diagnosis might develop in the years to come.

The clinical picture and the histological findings in a case of hydrops endolymphaticus cochleae is given. The case is remarkable because of an unusual degeneration of the first neurons in the apical turn of the right ear. There is also a beginning hydrops in the apical turn of the opposite ear. Neither clinically nor histologically could signs of a vestibular dysfunction be found. The findings are discussed.

Results of independently interpreted computerized stationary platform posturography and white noise rotational tests were compared with diagnoses for 110 patients. Using the criterion that an abnormal result from either test classified the subject as abnormal, the sensitivity estimate for the pair of tests was 78 % for persons with diagnoses known to result in vestibular dysfunction. The specificity estimate was 90%. Both a vestibulo-ocular and a vestibulo-spinal test were required for effective screening. Consecutive tests performed over five days showed the rotation test to be much less variable than posturography. Rotation testing is therefore preferred for following the performance of patients having disorders thought to cause fluctuating vestibular systems. Interob-server reliability rates were 83 % for posturography and 93% for rotation tests.

In 205 patients with unilateral hearing loss, 117 of cochlear and 88 of retrocochlear origin, thorough audiovestibular examinations were performed to establish the occurrence and severity of vestibular dysfunction. The results were also analysed with the aim of determining the relationships between the severity of the hearing loss, the etiology and the topical location of the hearing disorder, on the one hand, and vestibular dysfunction, recorded as reduced caloric sensitivity and occurrence of oculomotor disturbances, on the other. No correlation was found between severity of hearing loss and recordable vestibular dysfunction, in either the cochlear or retrocochlear group of patients, or in the etiological subgroups of these main groups. With respect to the relations between the topic locations of the lesions and the results of vestibular tests, distinct characteristics were observed. In the affected ears, totally extinguished caloric reactions were more than six times as frequent in the retrocochlear group as in the cochlear group and appeared as a specific but rather insensitive sign of acoustic neurinoma. Oculomotor disturbances were only exceptionally observed in patients with cochlear lesions, but were noted in nearly half of the retrocochlear group; when only those patients with lesions of the brain stem or cerebellum were considered, all were found to exhibit such disturbances. The relations between audiometric hearing test pattern, caloric sensitivity and oculomotor disturbances seem to form interesting diagnostic paradigms of great value for the topical localization of audiovestibular disorders.

Brief whole-body movements (+/- 5 to 170 degrees/s peak velocity; approximately equal to 0.5 s duration), applied during 1.44-s intervals of total darkness while subjects "looked" at a just-viewed target, were used to examine vestibulo-ocular function in 3 patients who had compensated to total unilateral loss of peripheral vestibular function. We found that the combined effects of slow-phase and saccadic eye movements both tended to keep the eyes stabilized on the unseen target. Compensatory slow-phases elicited during rapid head movements ipsilateral to (i.e., towards) the lesion were only about 60% as effective as those elicited during rapid contralateral movements. Compensatory gaze-correcting saccades tended to supplement deficient slow-phase movements, especially during rapid ipsilateral head movement. However, the gaze-correcting effect of saccades was only about half of the required for perfect stabilization. Thus, two functional vestibular deficits were observed during rapid ipsilateral head movements: (1) reduced slow-phase stabilization, and (2) reduced saccadic ability to adequately supplement the deficient slow phases. However, overall vestibular functional capability, as assessed by observation of the net effect of both slow phases and saccades, was much better than would be indicated by conventional observation of slow-phase movements alone.

Patients scheduled for major oncologic head and neck surgery underwent preoperative audiometry and rotational testing for vestibulo-ocular response (VOR). Patients with normal preoperative VOR and SRT less than 45 dB were subsequently retested following surgery for VOR. Patients deemed abnormal on postoperative rotational testing were retested until VOR returned to normal or one year, whichever came first. Eighty patients had normal VOR measured preoperatively. At the first postoperative testing 46 of these patients (58%) were determined to have significant VOR abnormalities. No differences in length of anesthesia, use of hypnotic or narcotic drugs, hepatic and renal abnormalities, and dehydration were noted in the patients who developed abnormal VOR, when compared to the patients who maintained normal VOR. One year post surgery twenty patients (43%) continued to demonstrate vestibular abnormality. The observation that major surgery reduces vestibular response has important monitoring and treatment implications. The integration of this data with the results of endolymphatic surgery are discussed.