Inter-rater agreement on identification of electrographic seizures and periodic discharges in ICU EEG recordings

Abstract

Objective This study investigated inter-rater agreement (IRA) among EEG experts for the identification of electrographic seizures and periodic discharges (PDs) in continuous ICU EEG recordings. Methods Eight board-certified EEG experts independently identified seizures and PDs in thirty 1-hour EEG segments which were selected from ICU EEG recordings collected from three medical centers. IRA was compared between seizure and PD identifications, as well as among rater groups that have passed an ICU EEG Certification Test, developed by the Critical Care EEG Monitoring Research Consortium (CCEMRC). Results Both kappa and event-based IRA statistics showed higher mean values in identification of seizures compared to PDs (k = 0.58 vs. 0.38; p < 0.001). The group of rater pairs who had both passed the ICU EEG Certification Test had a significantly higher mean IRA in comparison to rater pairs in which neither had passed the test. Conclusions IRA among experts is significantly higher for identification of electrographic seizures compared to PDs. Additional instruction, such as the training module and certification test developed by the CCEMRC, could enhance this IRA. Significance This study demonstrates more disagreement in the labeling of PDs in comparison to seizures. This may be improved by education about standard EEG nomenclature.

Diagnostic accuracy between readers for identifying electrographic seizures in critically ill adults

“…), indicating that differences existed in annotation of onsets and offsets when readers’ annotations overlapped. The above information cannot be obtained through kappa statistics, which was often used in many prior studies to demonstrate IRA on preselected short (often < 1 h) EEG segments containing mainly confirmed seizures without accounting for IRA on nonseizure periods . We focused on longer (>1.5 h) original EEGs, containing mostly (median of 94%, calculated from Table ) nonseizure duration.…”

“…Immediate identification of electrographic seizures is important for early diagnosis, appropriate management, and accurate prognosis estimation in patients with all types of brain injuries, especially in critically ill patients under intensive care . However, interpretation of electrographic seizures can be difficult for even the most experienced experts and can be even more challenging during continuous electroencephalogram (EEG) monitoring in intensive care units (ICUs) because of added complexity and uncertainty . So far, the extent to which difficult‐to‐interpret seizure‐like patterns, often known as equivocal seizure patterns or interictal‐ictal continuum, can compromise diagnostic accuracy and interreader agreement (IRA) in seizure detection in ICUs is still unknown.…”

“…experts [7][8][9] and can be even more challenging during continuous electroencephalogram (EEG) monitoring in intensive care units (ICUs) because of added complexity and uncertainty. [10][11][12] So far, the extent to which difficult-to-interpret seizure-like patterns, often known as equivocal seizure patterns 13,14 or interictal-ictal continuum, 15 can compromise diagnostic accuracy and interreader agreement (IRA) in seizure detection in ICUs is still unknown.…”

Modified device for fluid percussion injury in rodents

“…Clinical studies showed that post-traumatic seizures occur frequently in the intensive care unit (Halford et al, 2015;Vespa et al, 1999), and constitute potentially serious secondary injuries (Friedman, Claassen, & Hirsch, 2009), such as hippocampal atrophy (Vespa et al, 2010). Seizure spreading relies on the integrity of neural networks and their mutual interaction crossing different brain regions.…”

Semi-automated annotation of signal events in clinical EEG data

“…The interpretation of the EEG signals itself is quite subtle and challenging. For example, in [2] the inter-rater agreement on identification of electrographic seizures had a kappa statistic of 0.58. For periodic discharges, the kappa statistic was 0.38.…”