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The objective of the present study was to evaluate the potential of CT and MRI for diagnostics of congenital and acquired pathology of the inner ear in the deaf patients. Two groups of the patients were examined. The first group consisted of 75 patients with congenital or acquired deafness etiology. The second group was comprised of 75 patients with deafness associated with acute bacterial meningitis suffered in the preceding period. All the patients were examined by CT and MRI of temporal bones. The results of the study provided a basis for the development of indications for the application of CT and MRI to examine the patients presenting with hearing loss and deafness., Conclusion: CT and MRI make it possible to identify individual features of the temporal bone structure significant for the surgical treatment. MRI appears to have an advantage over CT for diagnostics of early obliteration of the cochlea. Both CT and MRI are the optional methods for the examination of the patients with deafness developing after meningitis.

The objective of the present study was to improve diagnostics of basilar type migraine (BTM) based on the results of neurological, vestibulometric, and audiological studies of 11 patients. Peculiarities of the clinical picture of this disease and the medical histories of these patients are described. The pathogenetic role of labyrinthine hydrops and the difficulties encountered in diagnostics of Meniere's disease are discussed.

This publication was designed to describe the clinical manifestations of dehiscence of the superior semicircular canal (Minor syndrome), currently employed methods for its diagnostics, and the first case of this pathology reported in this country with the good outcome of the treatment. Also described are the historical background relevant to the problem, pathomorphological changes in the superior semicircular canal, clinical manifestations of the disease, the patients' subjective complaints, and the methods for diagnostics of dehiscence of the superior semicircular canal (Minor syndrome). The successful diagnostics and treatment of a female patient presenting with the aforementioned case of Minor syndrome is considered in much detail.

Radionuclide tracing employed to study arterial and venous blood supply to the brain in 100 patients with angiogenic cochleovestibulopathies and lipid distress syndrome has provided information on perfusion of the brain, arterial and venous hemodynamics with reference to the form of cochleovestibular disorders and atherosclerotic defects of extra- and intracranial cerebral arteries.

The examination of 120 patients with verified labyrinthine fistulas (LFs) has demonstrated that perilymphatic LFs most often are caused by rupture of the cochlear window's membrane (54%). Among other reasons were broken base of the stapes (6%), the defect in the area of both windows (17%), rupture of the annular ligament of the stapes (15%), defects in the area of semicircular canals. Incompetence of the stapedial piston prosthesis is documented.

Vertical vestibuloocular reflexes (VVOR) were studied in 25 patients with unilateral labyrinthine lesions and in 22 healthy subjects. The technique of VVOR is based on stimulation of the internal semicircular canals of the labyrinth by active sagittal head subduction. Dysfunction of the vertical semicircular canals manifested with: VVOR asymmetry with stronger reflexes on the side of the labyrinth affection; predominance of upward VVOR; vertical components of the horizontal vestibuloocular reflexes were not so intensive as VVOR but had the same specific features.

Passive cervicoocular reflex (PCOR) was studied in patients with unilateral affection of the labyrinth at the stage of decompensation and subcompensation according to the following three criteria: nystagmic direction, reactivity coefficient and phasic deviation. In decompensation of unilateral vestibular dysfunction, PCOR presents intensively and asymmetrically while in subcompensation it becomes symmetric and less intensive. The PCOR is characterized as compensatory in unilateral lesion of peripheral vestibular system.

Based either on spontaneous or experimental vestibular reactions, diagnostic methods proposed by the authors seem most informative for differential diagnosis of internal ear diseases with simulating conditions. The main thing in the above diagnosis is the vestibular testing unit which provides objective synchronous registration of vestibular-somatic and vascular reactions. The necessity of comparing rotatory nystagmus to postnystagmus, the significance of latent spontaneous nystagmus interpretation are emphasized.

Short-latency acoustic evoked potentials (SAEP) were recorded in 40 patients with vestibulocochlear neurinoma and 15 patients with unilateral cochlear hypoacusis. The results were compared with their psychophysical audiometric parameters. In the case of neurinoma, electric responses typically showed elongation of single waves and intervals between two peaks. In addition, they also displayed two other features. One of them was horizontal or ascending configuration of the curve reflecting the latency/intensity function. This indicates the absence of an electrophysiological equivalent of the phenomenon of loudness increment acceleration and, in more general terms, the stability of responses: lack of SAEP wave shortening and enhancement of acoustic stimulation level. The second feature was deterioration of the pattern and disintegration of individual complexes with a greater number of realizations. This can be attributed to the lability of nervous structures, in the case of neurinoma. This feature may also be responsible for the generally recognized concept that in neurinoma primary SAEP waves are not detectable when the routine method of recording responses to a large number of stimuli is used. These parameters are pathognomonic of neurinoma of the vestibulocochlear nerve and are never identified in the case of unilateral hypoacusis caused by cochlear lesions.

This study demonstrated that biologically active points (BAP) of external ear were sensitive to ultrasonic treatment. In order to identify their characteristics, specific conductivity of tissues in the BAP area was measured (in microamperes) by an Elita 4-PEP unit equipped with a silver probe. Conductivity was measured in five points. Such points as i-feng, er-meng, nei-er were shown to influence the cochleovestibular system and exhibit conductivity of approximately 150 microA. The risk of point hyperactivity increased drastically by the 4th and 13th exposure in response to unilateral endaural pharmacophysical treatment with 0.4 W/cm2 ultrasound. The use of ultrasound of lower intensity (0.05-0.2 W/cm2) helped to avoid this complication. These observations suggest that phonopuncture can constitute a component of endaural pharmacophysical treatment of internal ear.

The model can furnish additional information about the vestibulary system, when evaluating caloric tests. The model has been built with certain assumptions being made. The nystagmus intensity (the slow component rate during maximum intensity) is assumed to be proportional to the difference between energy levels (EL) of the right and left vestibular nuclear complexes (NC). El of each NC is equal to the afferent flow (AF) plus its inherent activity (IA). During caloric (two warm and two cold) tests IA remains constant. AF at rest is equal to spontaneous activity of receptors and during stimulation it increases or decreases in a linear fashion. Parameters of the model are: difference between intensities of reactions to warm and cold tests, difference between EL of two (right and left) unstimulated NC, and ratio of nystagmus intensity to the stimulus for each labyrinth. The behavior of the model during vestibular dysfunctions of various origin (changes in one of AF characteristics or changes in IA of one NC) is discussed. The diagnostic application of the model is illustrated by the discussion of nystagmometric data. The conclusion about vestibular dysfunction and its etiology can be made on the basis of statistic analysis of parameters of the model in the norm.

Changes in the compensation of the sequences of the unilateral loss of the labyrinthine function were studied in rabbits. Destruction of the labyrinth was accompanied by ocular nystagmus, increase of frequency of respiration and heart contractions, and EEG-activation. Investigations carried out showed these reactions to be extinguished at different time. At the late periods of labyrinthectomy a considerable asymmetry of nystagmus reaction to the angular accelerations equal in intensity, but opposite in direction was revealed. Stimulation of an intact otolith labyrinth was accompanied by the appearance of positional nystagmus. The results obtained indicated imperfection of the compensatory mechanisms during complete unilateral loss of the vestibular function.

Some considerations on the mechanisms of vestibulo-vegetative disturbance in space flight are given on the basis of clinical observations, experience of otoneurological clinic, simulation experiments and examinations of cosmonauts. The starting point in these disturbances was a significant fact of blood redistribution in weightlessness and subsequent changes in hemodynamics, metabolism, etc. The body reactions to weightlessness seem to prepare pronounced vestibulo-vegetative reflexes to threshold and subthreshold vestibular stimuli induced by head and body movements in flight. Some aspects of the vestibular selection and training of cosmonauts are discussed from this point of view.

This paper describes an important problem of aerospace medicine, i. e. space motion sickness. The review surveys relevant Soviet and foreign publications. On their basis, including their own data, the authors discuss possible mechanisms of the sickness symptom-complex in the weightless state. The authors put forth their own ideas concerning current hypotheses of space motion sickness and discuss potential applicability of the theoretical concepts with respect to the prevention of this adverse symptom-complex. The authors describe selected outlines in the study of mechanisms of space motion sickness and in the development of specific countermeasures.

Forty-seven healthy test subjects were exposed several times each to linear acceleration of varying value. Depending on the acceleration value, they reported subjectively three types of sensations at the threshold level: nondiscriminated in terms of direction (P1, a = 8.0 +/- 2.5 cm/sec2), inverted (P2, a = 12.4 +/- 2.5 cm/sec2) and discriminated (P3, a = 16.1 +/- 3.5 cm/sec2). The acceleration value at which P2 was recorded caused most typical responses in different test subjects whereas that at which P3 was recorded induced greatest individual variations. Evoked potentials in response to linear acceleration were recorded in such a manner which excluded potential instrumental artefacts or possible contribution of eye movements, excitation of the hearing organ and muscle tone changes. The data obtained indicate that acceleration-induced evoked potentials are predominantly of vestibular origin and consist of three peaks, viz. P1, N1, and P2, the latencies of which are equal to 31.3 +/- 7.2, 69.1 +/- 9.1 and 157.6 +/- 10.5 msec at the threshold where they emerge. The peak P1 is most variable, the peak N1 is most stable and the peak P2 is characterized by the largest ratio of the interindividual variation to the individual variation.

Changes in ACTH, cortisol, beta-endorphin have been investigated during vestibulo-vegetative syndrome (VVS) and injections of dalargin (leu-enkephalin analog) and nalorphine (agonist-antagonist of opioid receptors) in 9 volunteers with low level vestibulo-vegetative stability. Cumulative coriolis acceleration test during rotations on a special chair was used for VVS modelling. Dalargin (1-4 mg), nalorphine (5 mg) and placebo (NaCl solution) were injected intravenously 5-15 min before rotation. A significant increase in ACTH, cortisol and beta-endorphin plasma levels has been observed. Mean positive linear correlation (r greater than +0.6) between ACTH and beta-endorphin and ACTH and cortisol was noted immediately after the test only when dalargin was injected. It is suggested that in VVS there develops a hormonal conflict, i. e. an adequate hormonal release is disturbed.

It was found during studies on man and experiments on animals that various neuromediator systems of the organism (M-cholinergic, H1-histaminergic, dopaminergic, and opioidergic) are involved in the genesis of VVS. In addition, animal experiments showed that of great importance in the process are different regulatory peptides, in particular, substance P and beta-endorphin. The findings indicate that some neuropeptides may be used in the future in man for VVS prevention. At neuronal level the role of opioid peptides in realization of vestibulovegetative reactions is decoded and a number of possible mechanisms of their action is established. The study of the human hormonal status in VVS revealed complex neuroendocrine changes occurring in the organism. Based on the knowledge of some neurohormonal and neurochemical mechanisms of VVS pathogenesis, a new drug prevention and therapy of seasickness was proposed, efficacy of opioid antagonists naloxone and nalorphine was shown.