Structural brain abnormalities in epilepsy with myoclonic atonic seizures

Solange Denervaud; Christian Korff; Joël Fluss; Judith Kalser; Eliane Roulet-Perez; Patric Hagmann; Sébastien Lebon

doi:10.1016/j.eplepsyres.2021.106771

Structural brain abnormalities in epilepsy with myoclonic atonic seizures

Epilepsy Res. 2021 Nov:177:106771. doi: 10.1016/j.eplepsyres.2021.106771. Epub 2021 Sep 21.

Authors

Solange Denervaud¹, Christian Korff², Joël Fluss², Judith Kalser³, Eliane Roulet-Perez³, Patric Hagmann⁴, Sébastien Lebon⁵

Affiliations

¹ Radiology Department, Lausanne University Hospital and University of Lausanne (CHUV-UNIL), Lausanne, Switzerland.
² Pediatric Neurology Unit, Geneva Children's Hospital, Geneva, Switzerland.
³ Pediatric Neurology and Neurorehabilitation Unit, Woman-Mother-Child Department, Lausanne University Hospital and University of Lausanne (CHUV-UNIL), Lausanne, Switzerland.
⁴ Radiology Department, Lausanne University Hospital and University of Lausanne (CHUV-UNIL), Lausanne, Switzerland; Connectomics Lab, Department of Radiology, Lausanne University Hospital and University of Lausanne (CHUV-UNIL), Lausanne, Switzerland.
⁵ Pediatric Neurology and Neurorehabilitation Unit, Woman-Mother-Child Department, Lausanne University Hospital and University of Lausanne (CHUV-UNIL), Lausanne, Switzerland. Electronic address: Sebastien.lebon@chuv.ch.

PMID: 34562678
DOI: 10.1016/j.eplepsyres.2021.106771

Abstract

Objective: Epilepsy with myoclonic atonic seizure (EMAS) occurs in young children with previously normal to subnormal development. The outcome ranges from seizure freedom with preserved cognitive abilities to refractory epilepsy with intellectual disability (ID). Routine brain imaging typically shows no abnormalities. We aimed to compare the brain morphometry of EMAS patients with healthy subjects several years after epilepsy onset, and to correlate it to epilepsy severity and cognitive findings.

Methods: Fourteen EMAS patients (4 females, 5-14 years) and 14 matched healthy controls were included. Patients were classified into three outcome groups (good, intermediate, poor) according to seizure control and cognitive and behavioral functioning. Individual anatomical data (T1-weighted sequence) were processed using the FreeSurfer pipeline. Cortical volume (CV), cortical thickness (CT), local gyrification index (LGI), and subcortical volumes were used for group-comparison and linear regression analyses.

Results: Morphometric comparison between EMAS patients and healthy controls revealed that patients have 1) reduced CV in frontal, temporal and parietal lobes (p = <.001; 0.009 and 0.024 respectively); 2) reduced CT and LGI in frontal lobes (p = 0.036 and 0.032 respectively); and 3) a neat cerebellar volume reduction (p = 0.011). Neither the number of anti-seizure medication nor the duration of epilepsy was related to cerebellar volume (both p > 0.62). Poor outcome group was associated with lower LGI. Patients in good and intermediate outcome groups had a comparable LGI to their matched healthy controls (p > 0.27 for all lobes).

Conclusions: Structural brain differences were detectable in our sample of children with EMAS, mainly located in the frontal lobes and cerebellum. These findings are similar to those found in patients with genetic/idiopathic generalized epilepsies. Outcome groups correlated best with LGI. Whether these anatomical changes reflect genetically determined abnormal neuronal networks or a consequence of sustained epilepsy remains to be solved with prospective longitudinal studies.

Keywords: Epilepsy with myoclonic atonic seizures (Doose syndrome); Local gyrification index; MRI.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Brain / diagnostic imaging
Child
Child, Preschool
Electroencephalography*
Epilepsy* / complications
Female
Humans
Magnetic Resonance Imaging
Prospective Studies
Seizures / complications
Seizures / diagnostic imaging