DISTRIBUTION IN TIME OF SEIZURES DURING PRESURGICAL EEG MONITORING

We studied the length of stay needed to record a certain number of sei zures in a highly selected group of patients with intractable epilepsy in the final stages of presurgical monitoring. The mean length of sta y needed to record one seizure was 2.9 to 3.7 days, depending on the r ecording technique, 4.5 to 5.5 monitoring days to record three seizure s, and 6.1 to 7.6 days to record five seizures. It took 5 days to reco rd at least one seizure in 90% of patients, 7 to 10 days to record thr ee seizures, and 8 to 12 days to record five seizures. One-third of al l patients had fewer than five seizures during their stay. Extrapolati ng from the results in our unit, we computed a need for 91 to 227 pres urgical epilepsy monitoring beds to evaluate 2,000 to 5,000 similar ep ilepsy surgery candidates requiring invasive monitoring in the United States each year. Additional beds would be needed to monitor patients admitted for other purposes.