Abstracts

The uncertainty of increased risks of seizure provocation due to conditions of the workplace is considered to contribute to the high rates of unemployment in patients with epilepsy. In Germany, the diagnosis of epilepsy frequently leads to restrictions concerning workplaces with computer monitor displays, even in patients without photosensitivity. Current knowledge about photosensitive patients does not give evidence for an increased risk of seizures in such a setting, e.g. because of the high refresh frequencies ([ge]75 Hz) of modern PC monitor displays; however studies with EEG registration in patients working at a PC monitor display have not been undertaken. Patients 16 years and older with a documented photoparoxysmal response (PPR), i.e. epileptiform EEG discharges (ED) provoked by intermittent photic stimulation (IPS), were included. They underwent a standardized EEG procedure with simultaneous video recording. It comprised three evaluation periods in randomized order, each lasting 10 minutes: 1) baseline period (resting condition), 2) PC-test period (reading and editing a text at a personal computer using a word processing program), 3) control period (reading and editing a similar text printed on a white paper). For the PC-test period, a commercially available personal computer with a 17 inches cathode ray tube (CRT) monitor display (resolution 800x600 dpi, refresh rate of 85 Hz) was used. The number and duration of ED during each of the evaluation periods were assessed by two blinded examiners. In addition, standard IPS was performed in order to document present PPR. Sixteen patients were evaluated. During the procedure, four did not show PPR on IPS and thus were excluded. In 8 of the remaining 12 patients, ED occurred at least during one of the three evaluation periods. There was no statistical significant increase in number and duration of ED in the PC-test period compared to the control and baseline periods. ED tended to occur more frequently in the baseline period. No clinical seizure was recorded during the study. In accordance with the current literature using IPS, this study does not give evidence for an increased risk of seizure precipitation in photosensitive patients when using a word processing program displayed on a commercially available 17[apos][apos] CRT PC monitor display. Thus, restrictions concerning workplaces with computer monitor displays such as office work are not warranted. (Supported by UCB Pharma GMBH, Kerpen, Germany.)