How small can the epileptogenic region be? A case in point

Neurology. 2017 May 23;88(21):2017-2019. doi: 10.1212/WNL.0000000000003962. Epub 2017 Apr 26.

Abstract

Objective: To present a case that demonstrates that seizures and interictal disturbances can be driven by a small area of functionally abnormal cortex.

Methods: Two novel functional MRI network analysis methods were used to supplement conventional seizure and lesion localization methods: (1) regional homogeneity to quantify local connectivity, or synchrony, with a resolution of less than 1 cm3 of cortex; and (2) small-worldness to combine information about whole brain network segregation and integration.

Results: After a small corticectomy in the dominant supramarginal gyrus (13 × 7 × 6 mm) limited to the area of abnormal local connectivity, and smaller than the PET and SPECT abnormalities, the patient has been seizure-free for 3 years with no language deficit. Whole brain network characteristics normalized (small-worldness) to that of healthy controls.

Conclusions: This case demonstrates that small areas of cortex may be highly epileptogenic, drive intractable epilepsy, and disrupt large-scale networks likely to be involved in core cognitive functions.

Publication types

  • Case Reports

MeSH terms

  • Adolescent
  • Brain Mapping
  • Epilepsies, Partial / diagnostic imaging*
  • Epilepsies, Partial / drug therapy
  • Epilepsies, Partial / physiopathology*
  • Epilepsies, Partial / surgery
  • Female
  • Humans
  • Magnetic Resonance Imaging
  • Neural Pathways / diagnostic imaging
  • Neural Pathways / physiopathology
  • Neural Pathways / surgery
  • Neuronal Plasticity
  • Parietal Lobe / diagnostic imaging*
  • Parietal Lobe / physiopathology*
  • Parietal Lobe / surgery
  • Treatment Outcome