Abstracts

A New Exploratory MRI Score for Determining the Prognostic Value of Peri-ictal MRI Abnormalities in Status Epilepticus

Abstract number : 2.21
Submission category : 5. Neuro Imaging / 5A. Structural Imaging
Year : 2023
Submission ID : 761
Source : www.aesnet.org
Presentation date : 12/3/2023 12:00:00 AM
Published date :

Authors :
Presenting Author: Giorgi Kuchukhidze, MD, PhD – Christian Doppler University Hospital, Centre for Cognitive Neuroscience, Member of the European Reference Network EpiCARE, Paracelsus Medical University of Salzburg, Austria. Neuroscience Institute, Christian Doppler University Hospital, Salzburg, Austria

Pilar Bosque Varela, MD – Neurology – Christian Doppler University Hospital, Centre for Cognitive Neuroscience, Member of the European Reference Network EpiCARE, Paracelsus Medical University of Salzburg, Austria; Lukas Machegger, MD, PhD – Neuroradiology – Christian Doppler University Hospital, Paracelsus Medical University, Salzburg, Austria; Tanja Prüwasser, MSc – Neurology – Christian Doppler University Hospital, Centre for Cognitive Neuroscience, Member of the European Reference Network EpiCARE, Paracelsus Medical University of Salzburg, Austria; Andreas Oellerer, PhD – Christian Doppler University Hospital, Paracelsus Medical University, Salzburg, Austria; Jürgen Steinbacher, PhD – Neuroradiology – Christian Doppler University Hospital, Paracelsus Medical University, Salzburg, Austria; Georg Zimmermann, PhD – Team Biostatistics and Big Medical Data, IDA Lab Salzburg, and Research and Innovation Management, Paracelsus Medical University, Salzburg, Austria; Mark McCoy, Prof. , MD – Neurology – Christian Doppler University Hospital, Centre for Cognitive Neuroscience, Member of the European Reference Network EpiCARE, Paracelsus Medical University of Salzburg, Austria; Johannes Pfaff, Prof. , MD – Neuroradiology – Christian Doppler University Hospital, Paracelsus Medical University, Salzburg, Austria; Eugen Trinka, Prof. , MD – Neurology – Christian Doppler University Hospital, Centre for Cognitive Neuroscience, Member of the European Reference Network EpiCARE, Paracelsus Medical University of Salzburg, Austria. Neuroscience Institute, Christian Doppler University Hospital, Salzburg, Austria. Karl Landsteiner Institute for Neurorehabilitation and Space Neurology, Salzburg, Austria

Rationale:

Status epilepticus (SE) is a neurological emergency frequently associated with peri-ictal MRI abnormalities (PMA). PMA commonly include diffusion restriction, hyperperfusion and high signal in T2-weighted images (including FLAIR). PMA can be completely reversible or persist and be followed by permanent alterations such as cortical laminar necrosis, mesial temporal sclerosis and focal brain atrophy. We aimed to determine a prognostic value of PMA for the severity and outcome of SE.



Methods:

We prospectively recruited 137 (58 women and 79 men) patients with a definite diagnosis of SE between February 2019 and April 2023 with a median age of 65 years (IQR 23). All patients underwent an MRI within the first 48 hours after the onset of SE. MRI protocol included the following sequences: Diffusion weighted image (DWI), Fluid attenuated inversion recovery (FLAIR), T1-weighted image with and without contrast application, Arterial Spin Labelling (ASL). We developed an experimental score for evaluating PMA based on three axes: 1) location; 2) size; and 3) distribution. Location for neocortex was defined at the lobar level (e.g. frontal, temporal, insular, etc.). Alterations in different MRI sequences (DWI, FLAIR, ASL; T1-weighted image with contrast substance, etc.) were considered as separate lesions (e.g., alterations in DWI and FLAIR in the same location were considered as two lesions, each lesion was given one point). Any structure other than neocortex (including hippocampus, cerebellum, etc.) was considered as “subcortical.”

The longitudinal size of the lesion was assessed: It was considered large if it was bigger than 35 mm for neocortex and 15 mm for subcortical structures.

Two independent reviewers blinded for EEG and clinical data assessed an MRI score. In case of discrepancies a third reviewer was involved.

An MRI score was correlated with the outcome data: admission to intensive care unit (ICU), days spent in ICU, 30-day mortality as well as clinical outcome scores (STESS, mSTESS, EMSE amd END-IT).

Results: The median MRI score was 1.0 (IQR 9.0, min. 0.0, max. 73.0). There was a substantial agreement between the two raters (Cohen Kappa Coefficient 0.69). Admission to ICU was required for 66/137 (48%) patients, in whom there was a weak positive correlation between days spent in ICU and an MRI score (Spearman correlation 0.39). There were moderate positive correlations between MRI score and two clinical outcome scores – EMSE and END-IT (Spearman correlation 0.66 and 0.57, respectively). There were no correlations between MRI score and STESS or mSTESS (Spearman correlation 0.07 and 0.14, respectively). The median MRI score in those patients who died was much higher as compared to that in survivors (10.5, IQR 7.5 vs. 0.0 IQR 9.0), however, due to a difference in sample sizes (16 non-survivors vs. 121 survivors), the statistical difference was not calculated.

Conclusions: An experimental MRI score in patients with SE reflects its clinical severity and may predict its outcome, however, a validation in other cohorts is needed.



Funding: The study was supported by FWF (Fonds zur Förderung der wissenschaftlichen Forschung), Austrian Science Fund; Project number KLI 969-B.



Neuro Imaging