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Dynamic Visual Tests to Identify and Quantify Visual Damage and Repair Following Demyelination in Optic Neuritis Patients
Published on: April 14, 2014
Visual field severity indices demonstrate dose-dependent visual loss from vigabatrin therapy.
Miriam Conway1, Robert P Cubbidge, Sarah L Hosking
1Department of Optometry and Visual Science, City University, London, UK. miriam.conway.1@city.ac.uk
Epilepsia
|January 11, 2008
Summary
Maximum daily dose of Vigabatrin (VGB) is the key factor predicting central visual field loss in epilepsy patients. High VGB doses increase the risk of visual field defects more than cumulative exposure or treatment duration.
Area of Science:
- Ophthalmology
- Neurology
- Pharmacology
Background:
- Vigabatrin (VGB) is an antiepileptic drug.
- VGB use is associated with visual field defects.
- Quantifying VGB-induced visual field loss is crucial for patient management.
Purpose of the Study:
- Develop an algorithm to quantify VGB-induced central visual field loss.
- Investigate the relationship between VGB dose (maximum, cumulative, duration) and visual field defects.
Main Methods:
- 31 epilepsy patients exposed to VGB were studied.
- Automated static visual field examination assessed central visual field loss.
- Multiple regression analyzed VGB dose parameters against visual field defect severity and symmetry.
Main Results:
- Maximum VGB dose significantly correlated with visual field defect severity in each eye.
- Maximum VGB dose also correlated with the symmetry of visual field defects between eyes.
Conclusions:
- Maximum daily VGB dose is the most reliable predictor of visual field defects.
- Higher maximum VGB doses pose a greater risk for visual field defects than cumulative dose or duration.
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