A novel B-vHIT classification framework enhances discrimination of non-peripheral vs. peripheral vertigo

This study aimed to investigate the potential role of binocular video head impulse test (B-vHIT) in distinguishing non-peripheral and peripheral vertigo.

A cohort of 46 healthy volunteers underwent B-vHIT to establish normative reference values. Concurrently, 104 patients presenting with acute vertigo (onset ≤ 72 hours) underwent B-vHIT and HINTS protocol. B-vHIT parameters were analyzed according to imaging-supported clinical diagnoses and compared with HINTS results. Further, a four-category framework was proposed to differentiate non-peripheral from peripheral vertigo.

Significant differences in Interocular Gain Asymmetry (χ(2) = 68.381, P < 0.001) and Interocular Gain Difference (χ(2) = 50.187, P < 0.001) were observed among groups, revealing a post-hoc hierarchical pattern in which peripheral ophthalmoplegic-related dizziness (POD) group had the highest values, followed by central vertigo, peripheral vertigo and healthy controls. An Asymmetry threshold of < 16 combined with a Difference threshold of < 0.2 achieved 86.4% sensitivity and 89.2% specificity in distinguishing non-peripheral from peripheral causes of vertigo. The Type I (Gain−, Difference−) and Type IV (Gain+, Difference+) patterns demonstrated high specificity (99%) and sensitivity (79%) for identifying non-peripheral vertigo.

The B-vHIT can serve as a useful tool to distinguish between two types vertigo. The classification framework integrating Gain and Difference should be further investigated for distinguishing non-peripheral vertigo from peripheral vertigo.