Characterizing chapeau de gendarme in pediatric epilepsy through systematic video-EEG evaluation

Area of Science:

• Pediatric Neurology
• Epileptology
• Clinical Neurophysiology

Background:

• Chapeau de gendarme (CdG) is an understudied semiology in pediatric epilepsy.
• Previous research focused on its localizing value in limited surgical cohorts.

Purpose of the Study:

• To systematically characterize the frequency and clinical features of CdG in children.
• To analyze CdG semiology across the pediatric age spectrum.

Main Methods:

• Retrospective analysis of video-electroencephalography (EEG) monitoring in 264 children (0-17 years).
• Definition of CdG: symmetrical mouth corner and chin contraction lasting ≥5 seconds.
• Assessment of CdG characteristics, co-occurring semiologies, and EEG patterns.

Main Results:

• CdG identified in 10.6% of patients, predominantly in focal epilepsies (p=.009).
• Median age of onset was 12.3 years, with increased frequency in older children.
• CdG seizures often occurred during sleep (p<.001), with frequent hyperkinetic behavior and progression to bilateral tonic-clonic seizures.

Conclusions:

• CdG is present in a significant proportion of pediatric epilepsy patients across all ages.
• Findings suggest a tendency for higher occurrence in older children.
• This study provides a basis for further research into CdG mechanisms.