Video head impulse test (vHIT) unravels the hidden pathology in chronic vestibular deficit

Abstract

Abstract Background The caloric test is persistently altered in chronic peripheral vestibular hypofunction (PVH). So, we cannot depend on it to measure the degree of compensation in chronic vestibulopathy patients who are still complaining. So our aim was to assess the utility of vHIT to discover the unrevealed pathology in those patients. Our study included 20 subjects with unilateral chronic PVH who were still complaining (study group) and 20 healthy volunteers (control group). Videonystagmography (VNG) and video head impulse test (vHIT) were applied to all the subjects. Results VNG and caloric test results showed compensation signs in the study group. The caloric test indicated unilateral weakness in the affected side. According to vHIT results, a comparison between the affected lateral canal, contralateral healthy lateral canal among the study group, Rt. lateral canal, and Lt. lateral canal among the control group revealed no significant difference (P = 0.789), while comparing anterior and posterior canals showed significant differences (P = 0.005, 0.025) respectively. Conclusion The caloric test assesses only the horizontal semicircular canal and it is persistently altered in unilateral chronic PVH. So, we cannot depend on it to measure the degree of compensation in chronic vestibulopathy patients who are still complaining nor to detect unrevealed pathology regarding ant or post semi-circular canal. So we can use the vHIT test to discover the unrevealed pathology in those patients.

Keywords

• VNG
• Caloric testing
• Video head impulse test (vHIT)
• Vestibular hypofunction