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Assessment of Static Graviceptive Perception in the Roll-Plane using the Subjective Visual Vertical Paradigm
Published on: April 28, 2020
Subjective visual vertical and horizontal: effect of the preset angle
Waheeda Pagarkar1, Doris-Eva Bamiou, Deborah Ridout
1Department of Audiovestibular Medicine, Royal National Throat, Nose, and Ear Hospital, London, England.
Archives of Otolaryngology--Head & Neck Surgery
|April 23, 2008
Summary
The subjective visual vertical (SVV) and horizontal (SVH) depend on the preset angle direction in patients with vestibular dysfunction. This finding is more pronounced in peripheral vestibular dysfunction (PVD) and Ménière
Area of Science:
- Neuroscience
- Ophthalmology
- Audiology
Background:
- Vestibular dysfunction impacts spatial orientation.
- Subjective visual vertical (SVV) and horizontal (SVH) are key indicators of vestibular function.
- Peripheral vestibular dysfunction (PVD) and Ménière's disease (MD) present unique challenges in assessing these parameters.
Purpose of the Study:
- To compare SVV and SVH in patients with long-standing unilateral PVD and MD against healthy controls.
- To investigate the relationship between the linear marker's preset angle direction and SVV/SVH measurements.
Main Methods:
- A prospective case-control study was conducted in a tertiary neuro-otology outpatient clinic.
- Seventeen healthy volunteers, 9 PVD patients, and 10 MD patients underwent detailed neuro-otological evaluations.
- Twelve SVV and SVH readings were collected per subject using random clockwise and counterclockwise preset angles.
Main Results:
- Abnormal SVV/SVH values in PVD and MD patients correlated with symptoms like dysequilibrium, otolithic involvement, acute vertigo, or canal paresis.
- A novel finding indicates SVV is influenced by the preset angle direction in all groups, particularly in PVD and MD patients.
- The SVV consistently tilted towards the preset angle's direction, with a weaker correlation observed for SVH.
Conclusions:
- The direction of the preset angle is a critical factor that must be considered when interpreting SVV and SVH values.
- This finding has implications for the accurate assessment and diagnosis of vestibular disorders.
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