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Published on: August 17, 2021
Detecting retinal vigabatrin toxicity in patients with partial symptomatic or cryptogenic epilepsy
Aylin Ardagil Akçakaya1, Sevda Gökçeer, Hasan H Erbil
1Department of Ophthalmology Göztepe Training and Research Hospital, Istanbul, Turkey. aardagil@gmail.com
European Journal of Ophthalmology
|February 16, 2010
Summary
Optical coherence tomography (OCT) effectively detects vigabatrin toxicity by measuring reduced retinal nerve fiber layer thickness (RNFLT) in epilepsy patients. Other visual tests may be inconclusive for monitoring this specific toxicity.
Area of Science:
- Ophthalmology
- Neurology
- Pharmacology
Background:
- Vigabatrin is an antiepileptic drug used for specific seizure types.
- Detecting vigabatrin-induced retinal toxicity can be difficult in epilepsy patients due to pre-existing visual field defects.
- Objective assessment of retinal damage is crucial for managing vigabatrin therapy.
Purpose of the Study:
- To evaluate the efficacy of retinal nerve fiber layer thickness (RNFLT) measurement using optical coherence tomography (OCT) in detecting vigabatrin toxicity.
- To compare RNFLT, contrast sensitivity, color vision, and perimetry in epileptic patients on vigabatrin versus other antiepileptics and healthy controls.
- To determine the utility of these visual function tests as markers for vigabatrin-related retinal damage in specific epilepsy subgroups.
Main Methods:
- Cross-sectional study comparing 38 epilepsy patients (14 on vigabatrin, 10 on sodium valproate, 14 on carbamazepine) with 16 healthy controls.
- All participants underwent RNFLT imaging via OCT, contrast sensitivity testing, color discrimination assessment, and perimetry.
- Vigabatrin-related retinal damage was assessed by comparing OCT and visual function test results across groups.
Main Results:
- Vigabatrin group showed significantly reduced average 360-degree RNFLT compared to other groups.
- Significant RNFLT reduction was observed in all quadrants except the temporal sector in the vigabatrin group.
- No significant differences in mean deviation, contrast sensitivity, or color discrimination were found between patient groups, though all were lower than controls.
Conclusions:
- RNFLT measurement using OCT is an effective method for identifying vigabatrin toxicity in patients with partial symptomatic or cryptogenic epilepsy.
- Standard perimetry, contrast sensitivity, and color discrimination tests may yield inconclusive results for monitoring vigabatrin toxicity in these patient subgroups.
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