Other less common reflex epilepsies also tend to be described in patients of this age group. If a history of seizures in response to specific stimuli is reported, it is important to elicit as many details as possible about the nature of the provoking stimuli. In addition, a detailed description from the patient and family members of seizure symptoms is important. Determination of whether the seizure has features suggestive of focal or generalized onset guides subsequent diagnosis and treatment. Visually induced seizures may result from flickering light, removal of visual fixation or light intensity, complex visual patterns, viewing particular objects, or other visual stimuli.
Seizures occurring in photosensitive epilepsy are the most common type of visually induced seizures.
In susceptible patients, seizures or epileptiform EEG discharges are produced by stroboscopic light patterns. When clinical seizures occur, they are most often generalized seizures, either absence or myoclonic seizures that can progress to generalized tonic-clonic seizures. Alternatively, complex partial or other seizure types may be seen. In pattern-sensitive epilepsies, seizures are produced by particular visual patterns. These triggers may consist of circles, stripes, or other patterns, usually of high contrast.