Kurzfassung

Introduction: Status epilepticus (SE), representing the maximum expression of seizures, may be associated with enduring consequences. Peri-ictal MRI abnormalities (PMA) encompass a spectrum of alterations that manifest around the time of SE in select patients, observable across diverse MRI sequences. However, who will develop PMA remains unclear, and the specificity of these alterations has yet to be systematically investigated. Furthermore, a suitable time window for PMA appearance is uncertain. PMA, as an early sign of cerebral brain damage, may serve as a prognostic biomarker for predicting outcomes in SE. These abnormalities are expected to exhibit SE-specificity when compared to other neurological aberrations. Additionally, we anticipated that PMA may play a dual role: aiding the diagnosis of SE in ambiguous cases and being potentially predictable through electro-clinical data. Furthermore, we expect higher frequency and severity of MRI lesions in refractory-SE (RSE) or long-duration cases.

Methods: A prospective recruitment of patients with SE was conducted between February 2019 and April 2023, focusing on those who underwent MRI within 48 hours after SE and follow-up after SE. PMA locations were compared to lesion sites in the control group comprising individuals with other neurological conditions. Electro-clinical features were analyzed to characterize PMA development, and a study of irreversible lesions following SE was conducted. Outcome variables were compared between patients with and without PMA.
Results: PMA were observed in 105/204 (51%) of the patient cohort, with peri-ictal hyperperfusion documented in 48%, diffusion-restricted lesions in 29%, and hyperintense signal in fluid-attenuated inversion recovery (FLAIR) 26%. Most patients who underwent MRI follow-up-42/62 (84%) had reversible lesions, while 10/62 (16%) patients developed irreversible lesions. Specific PMA locations, such as the hippocampus and pulvinar of the thalamus, exhibited high specificity when contrasted with the control group. Factors linked to a higher likelihood of PMA occurrence included prolonged SE duration, refractoriness, a decreased level of consciousness, and lateralized electro-clinical features. PMA can be employed as a prognostic biomarker, as it correlates with increased mortality rates, ICU admission, and higher scores in the validated clinical outcome scores. Patients with ictal-interictal continuum (IIC) mirrored definitive-SE, presenting similar neuroimaging findings.

Conclusions: Beyond its use in etiological studies for SE, MRI is pivotal in managing SE patients. It serves as an outcome biomarker, helps delineate irreversible lesions, and aids in cases of ambiguous presentations.