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The Effect of Color on Light-Induced Seizures: A Case Report

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Abstract

Two to four percent of epileptics have their seizures triggered by flickering light, an effect which may be wavelength-dependent. We evaluated a patient with a long-standing history of light-induced petit mal seizures to determine if the seizures were triggered more effectively by a particular range of wavelengths and to determine whether this information could be used in the optometric management of such patients. Flickering lights of different wavelengths but equal luminance were presented while the patient's electroencephalogram (EEG) and subjective reports were monitored. The EEG results were not significantly different for different wavelengths, but the patient reported that longer wavelength light induced stronger seizures more consistently. Based on these results we concluded that the patient might benefit from spectacles tinted to exclude transmission of red light. The patient was given 4 pairs of 85% transmission spectacles, which differed only in lens tint (red, yellow, green, and blue), to try over a period of time. The patient felt that the tinted lenses were not dark enough to decrease his seizures effectively and he has opted to wear standard sunglasses. We feel this case shows that patients with light-induced seizures can benefit from optometric consultation. Because the patient's subjective report identified the clearest wavelength effect, we feel that it is reasonable for the general practitioner to suggest deeply tinted lenses to reduce the frequency of seizures in these patients.

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