Vestibular evoked myogenic potentials and digital vectoelectronystagmography's study in patients with benign paroxysmal positional vertigo

Ano: 2013 | Volume: 17 | Número: 2

Autores: Marta Maria da Silva Lira-Batista, Ricardo Schaffeln Dorigueto, Cristina Freitas Ganança

Palavras-chave: Vertigo; Vestibular Diseases; Vestibular Function Tests; Vestibular Evoked Myogenic Potentials

Resumo Inglês:

Introduction: Benign Paroxysmal Positional Vertigo (BPPV) is a very common vestibular disorder characterized by brief but intense attacks of rotatory vertigo triggered by simple rapid movement of the head. The integrity of the vestibular pathways can be assessed using tests such as digital vectoelectronystagmography (VENG) and vestibular evoked myogenic potentials (VEMP). Aim: This study aimed to determine the VEMP findings with respect to latency, amplitude, and waveform peak to peak and the results of the oculomotor and vestibular components of VENG in patients with BPPV. Method: Although this otoneurological condition is quite common, little is known of the associated VEMP and VENG changes, making it important to research and describe these results. Results: We examined the records of 4438 patients and selected 35 charts after applying the inclusion and exclusion criteria. Of these, 26 patients were women and 9 men. The average age at diagnosis was 52.7 years, and the most prevalent physiological cause, accounting for 97.3% of cases, was ductolithiasis. There was a statistically significant association between normal hearing and mild contralateral sensorineural hearing loss. The results of the oculomotor tests were within the normal reference ranges for all subjects. Patients with BPPV exhibited symmetrical function of the semicircular canals in their synergistic pairs (p < 0.001). The caloric test showed statistically normal responses from the lateral canals. The waveforms of all patients were adequate, but the VEMP results for the data-crossing maneuver with positive positioning showed a trend toward a relationship for the left ear Lp13. There was also a trend towards an association between normal reflexes in the caloric test and the inter-peak VEMP of the left ear. It can be concluded that although there are some differences between the average levels of the VENG and VEMP results, these differences were not statistically significant. Conclusion: In conclusion, the results of audiologic assessment, hearing thresholds, positioning maneuvers, and caloric tests have no effect on the quantitative results of VEMP. Additional research is warranted to establish the relationships among VENG, VEMP, and BPPV, especially as concerns the oculomotor tests.