Genes important for otoneurological diagnostic purposes - current status and future prospects.

SUMMARY: This review focuses on the current knowledge of the genes responsible for non-syndromic hearing loss that can be useful for otoneurological diagnostic purposes. From among a large number of genes that have been associated with non-syndromic hearing impairment, we selected several best-known genes, including the COCH gene, GJB2, GJB6 and SLC26A4, and we describe their role and effects of mutations and prevalence of mutations in various populations. Next, we focus on genes associated with tinnitus. Important areas for further research include assessment of genes potentially involved in pathophysiology of tinnitus and vertigo, which have traditionally been considered as being of otological aetiology, while advances in neuroimaging techniques have increasingly shifted studies toward neurological correlations.

The effect of betahistine on vestibular habituation: comparison of rotatory and sway habituation training.

This study was designed to investigate the effect of histaminergic agonists and antagonists on the acquisition of vestibular habituation. The experimental animals, pigeons, were subjected to unilateral rotatory and sway habituation training sessions. The habituation of postural reflexes and post-rotatory head nystagmus was assessed. Vestibular habituation in the control group was achieved by adopting the kinetic reflex posture after approximately 9 training sessions, and after 10 and 14 training sessions, respectively for 50% reduction of the total number of beats (TNB) and the duration of post-rotatory head nystagmus. In the sway adaptation test control pigeons needed nearly 15 training sessions while pigeons receiving betahistine adapted after approximately 8 sessions. Administration of histamine and, most notably, betahistine accelerated the process, while both H1 and H2 antagonists (clemastine, cimetidine) tended to retard it, indicating a less significant contribution of H2 receptors. The cholinergic agent physostigmine strongly retarded habituation while the anticholinergic agent scopolamine markedly accelerated it. In addition the adrenomimetic agent ephedrine also accelerated habituation while the adrenolytic agent droperidol retarded reduction of nystagmus beats. The results indicate that histaminergic receptors play a significant role in the vestibular habituation mechanism but are intricately involved with other types of receptors. Betahistine is clearly the agent of choice for attenuating vestibular effects.

[Hyperlipidemia in patients with inner ear disturbances]. / Hiperlipoproteinemie w zaburzeniach funkcji ucha wewnetrznego.

The aim of this study was to evaluate the occurrence of hyperlipidemia in patients suffering from vertigo, and/or tinnitus and/or hearing loss of unknown origin. 48 patients (25 women and 23 men) were included into this study. All patients had a negative previous medical history of any metabolic, cardiovascular or neurological disorders. Our results were compared to the control group of 31 healthy persons (16 women and 15 men). All subjects had a complete neurootologic examination, appropriate audiometric and vestibular studies. In biochemical evaluation lipid phenotype studies were performed. Hyperlipidemia were classified according to Friedricson criteria. There were some differences in lipid phenotype and severity of hyperlipidemia between this two group.

Stabilometric evaluation of equilibrium in patients with damage to the cervical spine.

The purpose of the present article is the stabilometric evaluation of patients with disorders of the cervical spine. The research involved 106 persons with spinal damage in the cervical segment due either to degenerative disease or traumatic injury. The examinations, performed on a Freyss stabilometric platform, involved the evaluation of particular parameters of platform movement. Head torque was also measured by using a special attachment. Improvement in posture coordination was demonstrated in the period from one month to one year after surgical fixation of the spine, as was the negative impact of an orthopedic collar on vestibulospinal reflexes. The results here recorded are associated with changes in cervical proprioception, reliably evaluated by comparing traditional platform movement results with the parameters used to evaluate shifts is head position.

Visuoocular reflexes in presbyvertigo.

Using electronystagmography, we tested 100 patients (ages 65-80 years) manifesting the clinical signs of presbyvertigo, for the purpose of demonstrating their visuoocular reflexes. We administered not only simple optokinetic and eye-tracking stimuli but caloric modification of each one as well (with contrary directed optokinetic trace movement). The results were compared with those obtained in a group of 40 healthy subjects between the ages of 20 and 25 years. In the older group, we observed a statistically significant increased frequency of asymmetry of optokinetic nystagmus and pathological patterns revealed by the eye-tracking test and caloric modification of both the optokinetic and eye-tracking tests. We discuss the hypothetical predominant localization of age-dependent changes, with emphasis on the disturbances of visual-vestibular integration, on the basis of data obtained from anamnesis and other electronystagmographic findings.

[Electronystagmographic and videonystagmographic studies in cerebello-pontine angle tumors]. / Diagnostyka elektronystagmograficzna i videonystagmograficzna w guzach kata mostowo-mózdzkowego.

Otoneurological investigations were carried out in 24 patients with cerebello-pontine angle tumors demonstrated in computed tomography. Standardized history taking was followed by electronystagmographic and videonystagmographical tests. In no case correct electrophysiological results were obtained. Eye-tracking test and gaze nystagmus were most frequently abnormal and together with other data these abnormalities indicated the location of the process. A more extensive use of videonystagmography was postulated.

[The vestibular system and migraine in children]. / Uklad przedsionkowy a migrena u dzieci.

Migraine in childhood is relatively common disease. Although clinical practice and scientific publications recognize frequent association of migraine and vestibular disorders, relationships have yet to be well defined. In present study the vestibular function was extensively tested in 20 children suffering from migraine. All the patients underwent complete neurootological examination including tonal threshold audiometry, testing of vestibulo-spinal reflexes--Romberg and Unterberger-Fukuda tests, Dix-Halpike test for BPPV, videonystagmography. On videonystagmography each patient was evaluated regarding: calibration, spontaneous nystagmus, gaze nystagmus, eye tracking test, optokinetic and positional nystagmus, and caloric testing. The same procedure have been performed regarding control group comprised of 15 healthy. All the patients with migraine presented abnormalities in vestibular testing. Analysis of the results showed that: functional state of structures forming both visuo-ocular and vestibulo-ocular structures was altered in all the migraine patients evaluated in the study, pathological findings suggest mainly central localisation of vestibular dysfunction in children suffering from migraine, the number of pathological VNG findings seems not to be correlated with the type of migraine.

Electronystagmographic study in chronic schizophrenia.

The authors reached the neurological and psychiatric diagnosis of chronic schizophrenia in 20 patients after examination of both vestibulooculomotor and visuooculomotor reflexes on electronystagmography. The type and intensity of the disease were established on adequate scales, and the entire group was tested in the remission stage, during the absence of psychotic signs. Electronystagmographic study, particularly the eye-tracking test with caloric modification, revealed the significant pathology of optokinetic nystagmus. The disturbances of the suppression effect of fixation on caloric nystagmus were observed in one-half the cases. Caloric stimulation demonstrated no case of canal paresis and a very small amount of directional preponderance.

[Vestibular findings in children's epilepsy]. / Badania narzadu przedsionkowego u dzieci z padaczka.

20 children between ages 6 and 15 who suffered from epilepsy classified according to suggestions of International League Against Epilepsy to partial seizures evolving to generalized seizures were tested otoneurologically. The aim of the study was to estimate the frequency and location of vestibular disturbances coexisting with the disease. Subjective and objective (using electronystagmography--ENG--and videonystagmography--VNG) otoneurological study was performed. Dizziness was noted in most cases. Nobody demonstrated normal ENG/VNG recordings and the character of the pathology suggested its central origin. Eye-tracking proof and optokinetic nystagmus (cortical and subcortical) revealed to be most helpful during diagnostic procedures. No correlation between the location of EEG pathological patterns and ENG pathological signs was proved.

[Electrophysiological examination (ENG, EEG) in Alzheimer's disease]. / Badania elektrofizjologiczne (ENG, EEG) w chorobie Alzheimera.

The aim of the study was the electronystagmographic and electroencephalographic examination in patients with clinical diagnosis of Alzheimer's disease. The results showed that visual-oculomotor and vestibulo-oculomotor disturbances have had the central origin. ENG and EEG examination showed the lesions of both frontal and temporal cortes in these patients.

Experimental hemispherectomy and hemicerebellectomy and their influence on vestibular habituation.

The aim of the study was to estimate the influence of hemispherectomy and hemicerebellectomy on acquisition and retention of vestibular habituation in pigeons. The habituation training was performed using a rotatory test. The frequency of head nystagmus and postural reflexes was examined before and after acquisition of habituation and some days later, for the evaluation of the retention process. Our results suggested that the hemispherectomy did not inhibit the acquisition of habituation but retention of this phenomenon was shorter at that time. The hemicerebellectomy made it impossible to reveal the vestibular habituation.

[Otolaryngologic symptoms from tumors of the posterior cranial fossa]. / Objawy otolaryngologiczne w guzach tylnego dolu czaszki.

The aim of the paper was the estimation of the otolaryngological signs in the patients with the tumor of posterior cranial cavity. Each one was underwent the otoneurological diagnosis inclusive of electronystagmography. The most frequent symptoms we noticed were headache, vertigo together with cerebellar signs and disorder of the VII, VIII and IX-th cranial nerves, The ENG seemed to be a useful method in a localizing process of intracranial damages.

[Otoneurological syndromes after cervical injuries]. / Zespoly otoneurologiczne po urazach kregoslupa szyjnego.

The aim of the work was the examination of vestibular and visual disturbances in patients after whiplash injury of the neck. The authors are of the opinion, that estimation of peripheral and central vestibular disorders are useful for defining of the clinical state of these patients.

[The prognostic values and correlations between Hockaday's (EEG) and Nathanson-Bergman's (ENG) scales in the context of new definition of death]. / Wartosci prognostyczne i wzajemne korelacje skali GCS, Hockaday'a (EEG) i Nathansona-Bergmana (ENG) w kontekscie nowej definicji smierci.

A group of 92 patients being under treatment in Intensive Care Unit of Neurosurgery Clinic in Bydgoszcz were observed using EEG, ENG and neurological findings. The eeg patterns, classified by Hockaday's scale, were related to the clinical stage, described using Glasgow Coma Scale, and the ENG patterns (Nathanson-Bergman's scale). Unfavourable prognosis was indicated by appearance of IV and V stage on Hockaday's scale and the caloric test seemed to mark the moment of complete breakdown of all brain-stem functions. The present paper demonstrated the value of EEG- and ENG patterns in description and forecasting of patients in coma.

[The prognostic value of EEG and ENG recording in deep coma]. / Wartosc prognostyczna badania elektroencefalograficznego i elektronystagmograficznego w glebokich stanach nieprzytomnosci.

The eeg and eng test were performed in 53 patients admitted in deep coma. The eeg patterns was analysed using Hockaday's scale and the eng test was appreciated by Nathanson-Bergman's scale. It was noticed that grade IV and V by Hockaday's scale and stage IV by Nathanson-Bergman's scale suggested malignant prognosis. Grade III in Hockaday's scale and stage II in Nathanson-Bergman's scale were unrelated to prognosis.

[Diagnostic value of the second phase nystagmus]. / Znaczenie diagnostyczne oczoplasów tzw. II fazy.

The aim of our work was the presence of the second phase nystagmus after rotatory, caloric and optokinetic irritation; estimation of this nystagmus magnitude and the clinical application of the second phase nystagmus. The investigation was performed in 30 healthy subjects and 65 cases of the peripheral and central vestibular pathology. Our results show that the second phase nystagmus appears more often after strong vestibular or visual irritation; the largeness of this reaction is bigger than the first reaction nystagmus. Only the asymmetry of the second phase nystagmus has the clinical apply. Labyrinthine disorders has the influence on the formation of the post-optokinetic reaction.

[Diagnostic value of the peripheral and central vestibular recruitment and decruitment]. / Przydatnosc badania obwodowej i osrodkowej postaci zjawiska wyrównania oraz odwróconego wyrównania przedsionkowego w diagnostyce otoneurologicznej.

The subject of our investigation was the diagnostic value of the distinguish of peripheral and central type of the vestibular recruitment and decruitment. The examination was performed in the healthy subjects and in the two groups of the peripheral and central vestibular pathology cases. For the definition of the presence of peripheral or central type of the recruitment/decruitment phenomenon we used Ghosh and Kacker method for the labyrinth irritation. The results of this study show that for more detail topographic diagnosis of the vestibular disorders one must search the type of recruitment and decruitment.