Chiari 1 Malformation and Epilepsy in Children: A Missing Relationship

Area of Science:

• Neurology
• Pediatric Neurosurgery
• Clinical Neuroscience

Background:

• The association between Chiari 1 malformation (CM1) and epilepsy is debated, with some considering it coincidental due to lack of clear links.
• Increasing CM1 diagnoses in children with seizures prompt re-evaluation of this association.
• Limited specific research exists on CM1 and pediatric epilepsy.

Purpose of the Study:

• To update current knowledge on the relationship between Chiari 1 malformation and epilepsy in children.
• To analyze a cohort of pediatric patients diagnosed with both CM1 and epilepsy.
• To compare these patients with those presenting CM1 symptoms without epilepsy.

Main Methods:

• Retrospective analysis of children diagnosed with CM1 and epilepsy (Group 1) versus CM1 symptoms +/- syringomyelia (Group 2) between 2015-2020.
• Exclusion of syndromic, tumoral, or other intracranial lesions.
• Complete preoperative work-up including MRI and EEG; surgical intervention for symptomatic CM1/syringomyelia patients; literature review.

Main Results:

• Group 1: 29 children (mean age 6.2 yrs) with CM1 and epilepsy; 27% had syringomyelia. Surgery in 31%, 62% seizure-free post-treatment.
• Group 2: 77 children (mean age 8.9 yrs) with CM1 symptoms (75%) and/or syringomyelia (39%). Mean tonsillar ectopia 11.8 mm.
• No significant differences in syringomyelia outcomes or CM1/syringomyelia regression between groups; no correlation between seizure freedom and PF decompression.

Conclusions:

• Findings do not support a clinical correlation between Chiari 1 malformation and epilepsy.
• Epilepsy course in CM1 patients is influenced by antiepileptic drugs, not surgical decompression.
• Literature review and study results suggest the association between seizures and CM1 is likely random.