Usefulness of a 1.5 T MRI-compatible EEG electrode system for routine use in the intensive care unit of a tertiary care hospital

Abstract

Continuous electroencephalogram (cEEG) recordings are being increasingly used in intensive care units (ICUs) to detect epileptic seizures and other changes. MRI scans can interrupt such recordings if the EEG electrodes need to be removed and important data can be missed. We retrospectively examined EEG recordings from ICU patients who underwent MRI scans, comparing those from patients with the MRI-compatible EEG electrodes with those who had to have the EEG electrodes removed before scanning. We also examined technical aspects of the recording and scalp abrasions in both groups. Fourteen of 31 (45%) EEG recordings with the MRI-compatible electrode system in patients that underwent MRI scans between 03:00 p.m. and 07:00 a.m. (when technologists were not available) captured seizures. In contrast, all of the six EEG recordings with the MRI-incompatible electrode system in patients that underwent MRI scanning during the same interval were interrupted and had no data. Recording characteristics of the EEGs were comparable between the two groups and none had scalp abrasions. A significant proportion of patients undergoing MRI scans with the MRI-compatible EEG electrodes had seizures that would have been missed if the MRI-incompatible EEG electrodes had been used.