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Network Analysis of the Default Mode Network Using Functional Connectivity MRI in Temporal Lobe Epilepsy
12:09

Network Analysis of the Default Mode Network Using Functional Connectivity MRI in Temporal Lobe Epilepsy

Published on: August 5, 2014

[Pathophysiology of medial temporal lobe epilepsy: role of cerebral dysgenesis]

Takato Morioka1, Tadao Kawamura, Kimiko Fukui

  • 1Laboratory of Dynamic Neuropathophysiology, Department of Neurosurgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.

No to Shinkei = Brain and Nerve
|May 8, 2002
PubMed

Insights

Cerebral dysgenetic lesions (CD) were found in operated medial temporal lobe epilepsy (MTLE) patients with hippocampal sclerosis. Microscopic cerebral dysgenesis was prevalent, suggesting congenital factors contribute to MTLE development.

Area of Science:

  • Neurology
  • Neuroscience
  • Epileptology

Background:

  • Medial temporal lobe epilepsy (MTLE) with hippocampal sclerosis is a common epilepsy syndrome.
  • The etiology of MTLE is not fully understood, with potential contributions from both acquired and congenital factors.

Observation:

  • This study investigated the incidence of macroscopic cerebral dysgenetic lesions (CD) in 39 operated MTLE patients with hippocampal sclerosis.
  • Four patients exhibited distinct CD, including meningocele, schizencephaly, focal cortical dysplasia, and periventricular nodular heterotopia.
  • Histological examination of resected temporal lobes from 29 MTLE patients revealed microscopic cerebral dysgenesis (microdysgenesis) in 28 patients.

Findings:

  • Microdysgenesis manifested as heterotopic white matter neurons, molecular layer neurons, oligodendroglial cell clusters, and dilated perivascular spaces.
  • The high prevalence of microdysgenesis (96.5%) in MTLE patients with hippocampal sclerosis is a significant finding.

Implications:

  • Congenital factors, alongside hippocampal sclerosis, appear to play a crucial role in the pathogenesis of MTLE.
  • These findings may inform diagnostic approaches and therapeutic strategies for MTLE, particularly in identifying patients with underlying dysgenetic conditions.

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