Hacia un nuevo VIII par: alternativas de baja complejidad / Towards a new vestibular assessment: low complexity alternatives

Introducción: El examen funcional del VIII par, mediante la prueba calórica permite conocer la función del canal semicircular horizontal, dejando de lado la evaluación de otras estructuras como el complejo utrículo-sacular. Objetivo: Evaluar el rendimiento diagnóstico de pruebas vestibulares de bajo costo y complejidad cefálico para suplir esta falencia. Material y método: En 34 pacientes con indicación de estudio funcional de VIII par se realizaron, además de las pruebas tradicionales, el test visual subjetivo vertical mediante prueba del balde, la prueba de impulso cefálico a ojo desnudo, y la aplicación del cuestionario de sintomatología "Dizziness Handicap Inventory". Resultados: Considerando el VIII par clásico como patrón de oro, se encuentra evidencia objetiva de patología en 50% de la muestra. Con la incorporación de los nuevos exámenes esta cifra aumenta a 85%. Se realizó análisis de discrepancia sobre pacientes con resultados normales en el estudio tradicional, pero anormal según los nuevos exámenes. El 100% de dicho grupo presenta una puntuación patológica en el cuestionario de síntomas. Más aún, los valores de desviación de verticalidad correlacionaron fuertemente con la puntuación de sintomatología (r =0,79; p =0,002). Conclusiones: El análisis de discrepancia sugiere que los nuevos exámenes son confiables en identificar patología en el estudio. Incluir en el estudio tradicional del VIII par pruebas de baja complejidad y corta duración (menos de 5 minutos en su conjunto) podría aumentar el rendimiento diagnóstico del estudio del equilibrio en hasta 35%.

Introduction: Traditionally, the assessment of vestibular function is based on the caloric test. This procedure assesses mainly the horizontal semicircular canal function, leaving other vestibular structures aside, such as the utricule-saccule complex. Aim: To assess the diagnostic performance low complexity tests to compensate for these issues. Material and methods: 34 patients with indication for vestibular assessment were recruited. In addition to traditional testing (caloric test and postural provocation maneuvers), the mentioned Subjective Visual Vertical and Head Impulse tests were applied alongside the Dizziness Handicap Inventory for vestibular symptoms. Results: Considering caloric testing and Dix-Hallpike maneuvers as gold standard, 50% of the sample presented an objective cause of their symptomatology. When including the new test, this value increases to 85%. A discrepancy analysis was conducted on the group with normal traditional tests and abnormal new tests. 100% of this group showed symptoms score above pathological levels. Furthermore, there was a strong relationship between deviation on the Visual Vertical test and symptomatology (r =0,79; p =0,002). Conclusion: The discrepancy analysis suggests that the new tests are reliable in determining pathology on this study. It these test are included to traditional testing, diagnostic performance may increase up to 35%.

Laboratory Vestibular Function Testing

Basically laboratory vestibular function testing use the vestibular ocular reflex and vestibular spinal reflex like as bedside examination or outpatients' evaluation. Such vestibular laboratory testing can aid diagnosis and can be used to document an abnormality suspected at bedside evaluation. The ability to perform serial vestibular evaluations allows an assessment over time of patients who are undergoing treatment for dizziness or treatment with potentially ototoxic medication. Generally speaking, it includes spontaneous nystagmus, some kinds of evoked nystagmus, ocular eye movement testing, Caloric's testing, rotational chair testing, vestibular evoked myogenic potential, subjective visual vertical, posturography and so on. Those testing have been developed with biomedical engineering based on the proven scientific facts together.

Retrospective Study of Magnetic Resonance Imaging & Vestibular Function Testing in Patients Suggestive of Central Vestibular Disorders

BACKGROUND AND OBJECTIVES:There were many tools to evaluate dizzy patients with various causes. Our aim was to find the relationship between the magnetic resonance imaging(MRI) and vestibular function testing(VFT) in patients who are supposed of central vestibular disorders and to evaluate their effects. MATERIALS AND METHODS:We selected 183 patients retrospectively by standardized questionnaires, physical examinations, chart reviews from 3,825 patients who visited otorhinolaryngology via department of emergency and out patient clinic with chief complaints of dizziness. Among them, 13 patients were supposed to have MRI in relation to dizziness. We analyzed the result of VFT, MRI findings and then classified them in according to lesion locations, pathologic findings in MRI & optokinetic tests, caloric tests, step velocity tests, vestibulo-ocular tests, visual fixation tests in VFT. RESULTS:There were 9 ischemic findings, 1 hemorrhagic finding, 3 neoplasms in pathologic findings. There were 5 pons lesions, 4 cerebellum lesions, 3 thalamus lesions, 2 medulla lesions, 2 pituitary lesions and 1 caudate nucleus lesions in locations. CONCLUSIONS:Dizzy patients visiting otorhinolaryngology OPD had 0.34%(13/3825) central origin vertigo, and vascular disease is most common. Therefore we supported that careful readings of VFT findings in identifying central vestibular disorders were valuable and might well represent the gold standard. MRI was an important tool for evaluating the central nervous system, and we should use MRI to assess central vestibular dysfunction. We concluded MRI correlated well with VFT findings of central vestibular dysfunction.