Contribution of Audiogram Classification in Evaluating Vestibular Dysfunction in Sudden Sensorineural Hearing Loss With Vertigo

Object: We aimed to identify the relationship between vertigo symptoms and the involvement of vestibular dysfunction in sudden sensorineural hearing loss (SSNHL) and the contribution of audiogram classification.Methods: A total of 50 patients with unilateral SSNHL were retrospectively divided into the vertigo group and non-vertigo group depending on the presence of vertigo. The involved vestibular end organs (VEOs) were verified by a battery of vestibular function tests including video head impulse test (vHIT), cervical vestibular-evoked myogenic potential (cVEMP), and ocular VEMP (oVEMP). The correlations of audiogram configurations, initial pure-tone average (PTA), number of involved VEOs, prognosis (complete recovery rate), and vestibular functions were analyzed between the two groups. Additionally, the vestibular functions in a subgroup of profound SSNHL patients were further compared within groups with or without vertigo.Results: Significant differences in the initial audiogram configurations (p = 0.033) and the abnormal rates of the posterior semicircular canal (PSC) (p = 0.035) and oVEMP (p = 0.046) were found between the two groups. The number of involved VEOs was related to the initial PTA in the vertigo group (p = 0.002, r = 0.541) and non-vertigo group (p = 0.042, r = 0.446). The prognosis was related to the abnormal rate of cVEMP and the number of involved VEOs in both vertigo group (p = 0.008, r = 0.482; p = 0.039, r = 0.385, respectively) and non-vertigo group (p = 0.016, r = 0.520; p = 0.022, r = 0.495, respectively), and it was especially related to the audiogram configurations in the vertigo group (p < 0.001, r = 0.692). However, after classification by audiogram configurations, there was no statistical difference in the abnormal rates of all vestibular function tests or the number of involved VEOs between the profound SSNHL patients with or without vertigo.Conclusion: The relationship between the involvement of vestibular dysfunction and vertigo symptoms in patients with SSNHL was significantly different before and after audiogram classification. When evaluating the vestibular dysfunction in SSNHL patients, more attention should be paid to the audiogram configuration.

Conventional vestibular function tests vs. butterfly vestibulometry in peripheral vertigo

Background: To perform conventional vestibular function tests & butterfly vestibulometry via electronystagmography (E.N.G.) in patients diagnosed clinically as suffering from peripheral vertigo. To rule out the presence of a central lesion in clinically diagnosed patients of peripheral vertigo. Methods: This is a prospective, cross-sectional, case series study conducted in 50 normal subjects and 138 patients clinically diagnosed as suffering from peripheral vertigo (excluding benign paroxysmal positional vertigo), who were subjected to conventional vestibular function tests &butterfly vestibulometry. Results: Conventional bithermal caloric test identified a nystagmus in 13.04% patients while E.N.G. assisted bithermal caloric test identified anystagmus in 91.30% patients. Thus in our study the sensitivity of identifyinga nystagmus increased 7 times when comparing conventional bithermal caloric test to E.N.G. assisted caloric test. During E.N.G., amongthe pathological group 8.96% had normal response, 80.43% had a peripheral lesion, 7.97% had a central lesion and 2.89% had a non-localizing lesion. Among the control group 96% had normal response and 4% had a peripheral lesion. Among the 11 central causes of vertigo diagnosed by E.N.G., 4 cases were also diagnosed by M.R.I. of brain but in 7 cases(63.63%) no structural pathology was seen. Conclusion: E.N.G. has 7 times more sensitivity to elicit nystagmus when compared to Fitzgerald Hallpike bithermal caloric test. E.N.G. can pick up central causes for vertigo amongst cases clinically diagnosed asperipheral vertigo. It has a better sensitivity to diagnose a central cause for vertigo when compared to M.R.I. of brain. Nepal Journal of Medical Sciences | Volume 03 | Number 01 | January-June 2014 | Page 31-37 DOI: http://dx.doi.org/10.3126/njms.v3i1.10355