A possible objective test to detect benign paroxysmal positional vertigo. The role of the caloric and video-head impulse tests in the diagnosis

Abstract

Background: Benign paroxysmal positional vertigo (BPPV) is characterized by vertigo lasting from seconds to minutes, induced by head movements. Objectives: Our study aimed to investigate the clinical significance of the caloric vestibular and video head-impulse tests (vHIT) diagnosing the disorder. Methods: 68 patients suffering from posterior canal BPPV (25 male, 43 females, mean age ± SD, 54.5 ± 13.2 years) and 56 patients with a normal functioning vestibular system as control were investigated. Bithermal caloric test and vHIT was performed during the same medical check-up. Canal paresis (CP%), gain (GA) and asymmetry (GA%) parameters were calculated. Results: The Dix-Hallpike manoeuvre was only positive in 4% of this population. The CP% parameter was only pathologic in two patients, and there was no significant difference between control and BPPV patients (p = 0.76). The GA value was never under 0.8 in this population, but GA% was abnormal in 63.2%. A significant difference comparing the GA% values to the control group was seen (p = 0.034). There was no correlation detected between the CP% and GA% values in BPPV. Regarding the GA% value, 61% sensitivity and 76% specificity was seen. Conclusion: The Dix-Hallpike manoeuvre was not often positive in the non-acute phase of BPPV; therefore, objective testing is essential. The caloric test does not have clinical significance in BPPV, but vHIT can be helpful based on the GA% parameter.

Keywords

• Caloric test
• Video-head-impulse test
• Benign paroxysmal positional vertigo
• Objective diagnosis