Mild encephalopathy with reversible splenial lesion: Description of nine cases and review of the literature

Lina Grosset; Hassan Hosseini; Blanche Bapst; Jérôme Hodel; Laurent Cleret De Langavant; Frédéric Faugeras; Anne-Catherine Bachoud-Lévi; Lilia Seddik

doi:10.1016/j.seizure.2021.03.032

Mild encephalopathy with reversible splenial lesion: Description of nine cases and review of the literature

Seizure. 2021 May:88:83-86. doi: 10.1016/j.seizure.2021.03.032. Epub 2021 Apr 3.

Authors

Lina Grosset¹, Hassan Hosseini², Blanche Bapst³, Jérôme Hodel⁴, Laurent Cleret De Langavant⁵, Frédéric Faugeras⁶, Anne-Catherine Bachoud-Lévi⁷, Lilia Seddik⁸

Affiliations

¹ Department of Neurology, Henri Mondor Hospital, Public Hospitals of Paris Organisation, Paris, France. Electronic address: lina.grosset@aphp.fr.
² Department of Neurology, Henri Mondor Hospital, Public Hospitals of Paris Organisation, Paris, France; Medical School, University of Paris XII, Créteil, France. Electronic address: hassan.hosseini@aphp.fr.
³ Department of Neuroradiology, Henri Mondor Hospital, Public Hospitals of Paris Organisation, Paris, France. Electronic address: blanche.bapst@aphp.fr.
⁴ Department of Neuroradiology, Henri Mondor Hospital, Public Hospitals of Paris Organisation, Paris, France.
⁵ Department of Neurology, Henri Mondor Hospital, Public Hospitals of Paris Organisation, Paris, France; Medical School, University of Paris XII, Créteil, France; Department of Cognitive Science, The Ecole Normale Supérieure, Paris, France; Mondor Institute for Biomedical Research, Inserm, Créteil, France. Electronic address: laurent.cleretdelangavant@aphp.fr.
⁶ Department of Neurology, Henri Mondor Hospital, Public Hospitals of Paris Organisation, Paris, France; Department of Cognitive Science, The Ecole Normale Supérieure, Paris, France; Mondor Institute for Biomedical Research, Inserm, Créteil, France. Electronic address: frederic.faugeras@aphp.fr.
⁷ Department of Neurology, Henri Mondor Hospital, Public Hospitals of Paris Organisation, Paris, France; Medical School, University of Paris XII, Créteil, France; Department of Cognitive Science, The Ecole Normale Supérieure, Paris, France; Mondor Institute for Biomedical Research, Inserm, Créteil, France.
⁸ Department of Neurology, Henri Mondor Hospital, Public Hospitals of Paris Organisation, Paris, France. Electronic address: lilia.seddik@aphp.fr.

PMID: 33839562
DOI: 10.1016/j.seizure.2021.03.032

Abstract

Mild encephalopathy/encephalitis with reversible splenial lesion (MERS) is a transient clinico-radiological syndrome characterized by non-specific encephalopathy and specific magnetic resonance imaging (MRI) pattern. MRI shows an ovoid lesion in the mid-splenium of the corpus callosum (SCC), with signal-intensity anomaly similar to stroke but vanishing within few weeks. Although there are a lot of child MERS cases descriptions, there are just a few adult-onset reported. Our goal is to provide a better clinical and radiological description of this entity. We reported nine adult-onset cases of MERS managed in our stroke unit between 2017 and 2019. The study of our adult series suggests that epilepsy and the context of an infection are very common in MERS. Adult cases show frequent focal neurological deficits and few encephalopathies compared to children. The measurement of very low ADC values in SCC lesion is a new radiological feature of MERS that should be systematically assessed in suspected cases to differentiate this complex syndrome from SCC strokes.

Keywords: Apparent diffusion coefficient; Encephalitis; Encephalopathy; Epilepsy; MERS.

Publication types

Review

MeSH terms

Adult
Brain Diseases* / complications
Brain Diseases* / diagnostic imaging
Child
Corpus Callosum / diagnostic imaging
Encephalitis* / complications
Encephalitis* / diagnostic imaging
Humans
Magnetic Resonance Imaging
Stroke* / complications
Stroke* / diagnostic imaging
Syndrome