In the April 2000 issue of the ARCHIVES, Cendes et al1 present a provocative study that suggests that in a certain highly selected subgroup of patients undergoing evaluation for temporal lobe epilepsy (TLE) surgery, one could dispense with ictal recordings before proceeding to resection. Because surgical outcome data are not provided, their claim is difficult to evaluate. Most epileptologists believe that the ictal electroencephalograph (EEG) is necessary for definitive lateralization because bilateral interictal epileptiform discharges are commonly observed in patients with strictly unilateral seizures.2 However, this study is the latest in a series of reports that indicate that it is possible to define a group of patients in which the interictal information is at least as informative as the ictal recordings in terms of lateralization and, furthermore, that discordance is extremely unlikely when the information is backed up by reliable quantitative structural magnetic resonance imaging (MRI) data.1,3,4 The benefits of dispensing with ictal recordings are obvious—a reduction in the potential risks associated with the need to withdraw anticonvulsant medication, a reduction in the time of inpatient stay, and a reduction in the overall cost of the hospital visit. While these are clearly admirable goals, we feel that the results of the study of Cendes et al do not address all of the issues that require resolution before it would be prudent to do away with long-term EEG monitoring.
Doherty CP, Cole AJ. The Requirement for Ictal EEG Recordings Prior to Temporal Lobe Epilepsy Surgery. Arch Neurol. 2001;58(4):678-680. doi: