Added value of advanced workup after the first seizure: A 7-year cohort study

Pia De Stefano; Eric Ménétré; Patrick Stancu; Pierre Mégevand; Maria Isabelle Vargas; Andreas Kleinschmidt; Serge Vulliémoz; Roland Wiest; Sandor Beniczky; Fabienne Picard; Margitta Seeck

doi:10.1111/epi.17771

Added value of advanced workup after the first seizure: A 7-year cohort study

Epilepsia. 2023 Dec;64(12):3246-3256. doi: 10.1111/epi.17771. Epub 2023 Oct 7.

Authors

Affiliations

¹ EEG & Epilepsy Unit, Department of Clinical Neurosciences, University Hospitals of Geneva, Geneva, Switzerland.
² Neuro-Intensive Care Unit, Department of Intensive Care, University Hospitals of Geneva, Geneva, Switzerland.
³ Neuroradiology Department, University Hospitals of Geneva, Geneva, Switzerland.
⁴ Institute of Diagnostic and Interventional Neuroradiology, Inselspital, University of Berne, Bern, Switzerland.
⁵ Department of Clinical Neurophysiology, Aarhus University Hospital, Aarhus and Danish Epilepsy Center, Dianalund, Denmark.
⁶ Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.

PMID: 37699424
DOI: 10.1111/epi.17771

Abstract

Objective: This study was undertaken to establish whether advanced workup including long-term electroencephalography (LT-EEG) and brain magnetic resonance imaging (MRI) provides an additional yield for the diagnosis of new onset epilepsy (NOE) in patients presenting with a first seizure event (FSE).

Methods: In this population-based study, all adult (≥16 years) patients presenting with FSE in the emergency department (ED) between March 1, 2010 and March 1, 2017 were assessed. Patients with obvious nonepileptic or acute symptomatic seizures were excluded. Routine EEG, LT-EEG, brain computed tomography (CT), and brain MRI were performed as part of the initial workup. These examinations' sensitivity and specificity were calculated on the basis of the final diagnosis after 2 years, along with the added value of advanced workup (MRI and LT-EEG) over routine workup (routine EEG and CT).

Results: Of the 1010 patients presenting with FSE in the ED, a definite diagnosis of NOE was obtained for 501 patients (49.6%). Sensitivity of LT-EEG was higher than that of routine EEG (54.39% vs. 25.5%, p < .001). Similarly, sensitivity of MRI was higher than that of CT (67.98% vs. 54.72%, p = .009). Brain MRI showed epileptogenic lesions in an additional 32% compared to brain CT. If only MRI and LT-EEG were considered, five would have been incorrectly diagnosed as nonepileptic (5/100, 5%) compared to patients with routine EEG and MRI (25/100, 25%, p = .0001). In patients with all four examinations, advanced workup provided an overall additional yield of 50% compared to routine workup.

Significance: Our results demonstrate the remarkable added value of the advanced workup launched already in the ED for the diagnosis of NOE versus nonepileptic causes of seizure mimickers. Our findings suggest the benefit of first-seizure tracks or even units with overnight EEG, similar to stroke units, activated upon admission in the ED.

Keywords: EEG; MRI; emergency department; first seizure; long-term EEG.

MeSH terms

Adult
Brain / diagnostic imaging
Cohort Studies
Electroencephalography
Epilepsy* / diagnostic imaging
Humans
Magnetic Resonance Imaging
Seizures* / diagnostic imaging