Abstracts

Rationale: Sedation for uncooperative pediatric patients is important to keep patients still during magnetoencephalography (MEG) measurement. We previously reported Total intravenous anesthesia (TIVA) of propofol affecting MEG spike sources (MEGSSs) especially for the patient without lesion. The purpose of this study is to evaluate the effect of propofol for MEG in same patients with and without TIVA. Methods: From August, 2000 to March, 2008 we performed MEG on 651 pediatric patients with intractable epilepsy. Among them 79 patients (12%) underwent MEG with TIVA. There were 10 patients underwent MEG with and without TIVA at the different time. There were 3 boys and 7 girls (age 14 months to 9 years old, mean age with TIVA 3.6 years old, mean age without TIVA 4.7 years old). We maintained Propofol 30-60 g/kg/min with remifentanil using nasal prong, laryngeal mask airway or endotracheal tube. MEG was performed with whole-head 151-channel gradiometers. Sampling rate was 625 Hz. We recorded 15 to 20 data sets of 2-minute periods. Results: Propofol of TIVA reduced the MEG spikes/minutes (3.5 with vs 5.7 without TIVA) and the MEGSSs/minutes (0.8 with vs 2.6 without TIVA). Propofol TIVA minimized the size of clustered MEGSSs in 5 patients, slightly expanded MEGSS cluster in one patient. MEGSSs disappeared under TIVA in 4 patients. The reduced and minimized cluster of MEGSSs under TIVA remained in the epileptogenic zone in 5 of 7 patients who underwent surgery. Five of 6 patients (83%) with neuronal migration disorders (NMDs) remained MEGSSs under TIVA. Conclusions: For the uncooperative patients with intractable localization related epilepsy, MEG with TIVA was worth performing for presurgical evaluation. Remaining lateralized MEGSSs with TIVA indicated the epileptogenic hemisphere to proceed resective surgery. The size of clustered MEGSSs can be minimized by TIVA. NMDs were intrinsically epileptogenic to present clustered MEGSSs even with TIVA.