Pattern sensitivity and photosensitivity in epileptic children with visually induced seizures.

We evaluated photosensitivity and pattern sensitivity in 74 epileptic children (38 males, 36 females aged 4.4-19 years; mean age 11.9 years) with reflex seizures induced by environmental visual stimuli and analyzed clinical and EEG characteristics of patients according to type of sensitivity. Standard procedures of visual stimulation were used in all cases. Seven children were excluded because of poor cooperation (3) or no activation (4). Fifty-one percent of the remaining 67 patients showed sensitivity to both light and pattern, whereas 33% showed photosensitivity and 16% showed pattern sensitivity. Generalized abnormalities were more frequently elicited by intermittent light stimulation than by pattern (73 vs. 36%, p < 0.001). Significant differences in clinical and EEG findings were noted among patients according to their sensitivity to light or/and pattern. In particular, pattern-sensitivity patients without photosensitivity had a higher occurrence of localization-related symptomatic epilepsies, neurologic abnormalities, and epileptiform EEG abnormalities, mainly focal, at rest.