[The clinical manifestations and neurophysiological features of long-lasting paroxysmal vertigo:theanalysis of the original observations].

The objective of the present study was to elucidate specific features of etiology and pathophysiology of recurring chronic vestibular dysfunction. It included 90 patients with this pathology of whom 24 (26.6%) presented with vascular compression of the vestibulocochlear nerve diagnosed by means of high-field MRI. This method revealed the high frequency of positionally-dependent vestibular dysfunction associated with neurovascular interactions. Analysis of the state of vestibular dysfunction during the attack-free periods demonstrated the signs of latent vestibular dysfunction in 20 (83.3%) patients. The results of the study provide additional information on the prevalence of vascular compression of the vestibulocochlear nerve in the patients presenting with recurrent chronic dizziness; moreover, they make it possible to evaluate the state of vestibular function and develop the new diagnostic criteria for vestibular paroxismia.

[Diagnostics of latent vestibular dysfunction based on the characteristics of provocative nystagmus].

The objective of the present study was to develop a new method for the diagnostics of latent vestibular dysfunction and estimate its effectiveness based on the characteristics of spontaneous nystagmus, provocative nystagmus, and vestibuloocular optokinetic reflexes in servicemen operating moving systems. Moreover, the study was designed to assess the diagnostic and prognostic value of the new method. The study involved a total of 95 patients in whom the vestibular function was evaluated by clinical methods. The analysis included parameters of spontaneous nystagmus and provocative nystagmus, vestibuloocular reflex and optokinetic nystagmus in the patients of different study groups. It was demonstrated that 83.33% of the patients presenting with the minimal neurologic deficit syndrome show the positive response in the Valsalva maneuver. The medical history of peripheral vestibular syndrome and syndrome of vertebrogenic vestibular dysfunction is significantly more frequently associated with positive results of the sinocarotid test (p<0.05) than other syndromes. Mean reactivity coefficients of the vestibuloocular reflex are high in both groups and show no asymmetry. Analysis of the likelihood ratio for positive responses confirms the prognostic value of individual algorithms and of the entire scheme of diagnostic examination for the detection of latent vestibular dysfunction.

[Vestibular paroxismia].

The objective of the present publication was to demonstrate a clinical case of peripheral vestibular paroxismia verified in a woman with the help of the MRI technique. Vestibular paroxismia is a relatively rare disease manifested in such characteristic signs and symptoms as sudden and short-lived episodes of dizziness, unstable gait, and the concomitant vegetative disorders accompanied as a rule by tympanophonia, impairment of hearing, and falls. In typical cases, the duration of such episodes varies from several minutes to a few days. A case of vestibular paroxismia associated with the lesion in the peripheral section of the vestibular system is described; it was caused by compression of the nerve by a blood vessel as shown by means of magnetic resonance imaging of cranial nerves.

[Vestibular disorders in the minimal cerebral dysfunсtion in adults].

Vestibular dysfunction is the most frequent symptom of minimal cerebral dysfunction in adults. Objective of the research was to study the etiopathogenesis of minimal cerebral dysfunction based on the analysis of the latency of different types of induced nystagmus. Threshold stimulation by physiological stimuli was used to study vestibular function (functional load tests) for the evaluation of neurodynamical plasticity of all parts of vestibular analyzer. Sixty males with manifestations of posterior cervical sympathetic syndrome, consequences of traumatic brain injury and neuroinfection, history of syncopes were examined. Spontaneous and different types of induced nystagmus were chosen as markers of vestibular dysfunction. Results of the study demonstrated that induced nystagmus had multineuronal arc, the latency of induced nystagmus was higher than that of spontaneous nystagmus and depended on the nature of stimulus applied to the vestibular system. In 3 patients, induced nystagmus was revealed in all tests with significant latency shortening compared to induced nystagmus in other patients. Functional load tests allowed to find a significant role of autonomic dysfunction, changes in the venous outflow and CSF flow in the cranial cavity and cervical proprioception in the etiopathogenesis of latent vestibular dysfunction in patients with minimal cerebral dysfunction.

[Diagnostics of latent vestibular disfunction among military servicemen with diseases of central nervous system in anamnesis].

There were studied peculiarities of provocative nystagmus among 60 military servicemen with nervous system in anamnesis. Latent vestibular disfunction--a frequently detected syndrome among persons with diseases of nervous system in anamnesis. To examine a provocative nystagmus, was used a range of vestibulometric loading tests, which influences on different parts of vestibular system. Was marked a high role of several loading testes in diagnostics of latent vestibular disfunction. It has been found that in conditions of syndrome of vegetative imbalance of different genesis, the most effective are tests of De Klein with hyperventilation and hyperventilation test. In conditions of minimal neurological deficit the most effective is tests of Valsalve. In conditions of peripheral vestibular syndrome in anamnesis and vertebral-genic vestibular disfunction a very effective is sinocarotid test.

[Spontaneous and provoked nystagmus in healthy subjects: on the so-called "vestibular" form].

A total of 25 healthy subjects were available for the study of provoked nystagmus using a series of vestibulometric functional tests affecting different component of the vestibular system. The study has demonstrates the high diagnostic value of provoked nystagmus and the importance of a series of vestibulometric functional tests as a tool for the evaluation of vestibular reactivity. Provoked nystagmus was documented in 3 cases using the full series of functional tests and was absent in 9 cases under the same conditions. It is concluded that observation of provoked nystagmus in individual tests reflects its etiology whereas its occurrence in the entire series of these tests suggests diagnosis of latent vestubular dysfunction.

[Diagnostic and expert value of functional tests in detection of latent vestibular dysfunction].

Vestibular dysfunction was studied in 150 patients with paroxysmal states and minimal neurological defect in the past. A series of functional stress tests proved to be highly effective in diagnosis of latent vestibular dysfunction.