Abstract

Background and objective: Video head impulse test (vHIT) are a new test that provides information about each semicircular canal function by quantifying the gain of the VOR and it detects refixation saccades, overt and covert saccades. Our aims to compare video head impulse test results among different vestibular lesions and healthy subjects. To correlate between video head impulse test and caloric test results.

Methods: Case control study in which the control group included 30 normal healthy subjects. The study group included 62 patients suffering from dizziness. The study group subdivided into four subgroups vestibular neuritis (VN), Meniere’s disease (MD), benign paroxysmal positional vertigo (BPPV) and central lesion subgroups. All subjects were submitted to videonystagmography (VNG) and v HIT tests.

Results: There was statistically significant difference in vHIT gain between VN subgroup & control group. There was no significant difference in vHIT results between control and central lesion subgroup. There was strong negative correlation between caloric test and vHIT gain result in VN, but weak in other subgroups. Sensitivity and specificity of vHIT in VN were 84.21% and 63.33 respectively. In MD were 63.21 and 86.67% respectively.

Conclusion: increased sensitivity of vHIT to large unilateral peripheral vestibular lesions. Caloric testing was a more sensitive measure than vHIT in peripheral vestibular lesions but in central lesion they are almost equal. Strong negative correlation between caloric test (UW %) and vHIT gain results in lateral SCC was found in VN lesion. It was weak in other vestibular lesions.

Keywords: (V HIT); Vestibular lesions; VNG