A new method to analyze the subjective visual vertical in patients with bilateral vestibular dysfunction

Area of Science:

• Neuroscience
• Vestibular System Disorders
• Ophthalmology

Background:

• Bilateral vestibular dysfunction significantly impacts spatial orientation.
• Accurate assessment of the subjective visual vertical (SVV) is crucial for diagnosing vestibular disorders.
• Conventional analysis of SVV data may not fully capture perceptual deviations.

Purpose of the Study:

• To evaluate the subjective visual vertical in patients with bilateral vestibular dysfunction.
• To introduce and validate a novel method for analyzing SVV data.
• To improve the diagnostic accuracy for visual vertical misperception.

Main Methods:

• Conducted static subjective visual vertical tests on 40 participants (20 healthy, 20 with bilateral vestibular dysfunction).
• Performed six SVV measurements per subject.
• Analyzed SVV data using both conventional numerical values and a proposed absolute value method.

Main Results:

• Conventional analysis showed minimal mean deviation differences between groups (0.326±1.13º vs. 0.301±1.87º).
• Analysis of absolute SVV values revealed significant differences (1.35±0.48º vs. 2.152±0.93º), with p<0.05.
• The absolute value method and range analysis demonstrated statistically significant differences in SVV deviations.

Conclusions:

• Analyzing absolute values of the subjective visual vertical provides a more precise reflection of misperception in bilateral vestibular dysfunction.
• The proposed absolute value analysis method enhances the sensitivity for detecting vestibular-related spatial orientation deficits.
• This approach offers a valuable tool for clinicians assessing patients with vestibular impairments.