Cognitive impairment in early onset epilepsy is associated with reduced left thalamic volume

Epilepsy Behav. 2018 Mar;80:266-271. doi: 10.1016/j.yebeh.2018.01.018.


Objective: The objective of this study was to investigate whether reduction of thalamic volumes in children with early onset epilepsy (CWEOE) is associated with cognitive impairment.

Methods: This is a nested case-control study including a prospectively recruited cohort of 76 children with newly-diagnosed early onset epilepsy (onset <5years age) and 14 healthy controls presenting to hospitals within NHS Lothian and Fife. Quantitative volumetric analysis of subcortical structures was performed using volumetric T1-weighted magnetic resonance imaging (MRI) and correlated with the results of formal neurocognitive and clinical assessment. False discovery rate was used to correct for multiple comparisons as appropriate with q<0.05 used to define statistical significance.

Results: Age, gender, and intracranial volume (ICV)-adjusted left thalamic volumes were significantly reduced in CWEOE with cognitive impairment compared to CWEOE without impairment (5295mm3 vs 6418mm3, q=0.008) or healthy controls (5295mm3 vs 6410mm3, q<0.001). The differences in left thalamic volume remained if gray matter or cortical/cerebellar volumes were used as covariates rather than ICV (q<0.05). The degree of volume reduction correlated with the severity of cognitive impairment (q=0.048).

Significance: Reduced left thalamic volume may be a biomarker for cognitive impairment in CWEOE and could help inform the need for further formal cognitive evaluations and interventions.

Keywords: Cognitive impairment; Epilepsy; Preschool; Thalamus; Volumetric MRI.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Brain / pathology*
  • Case-Control Studies
  • Child
  • Cognition*
  • Cognitive Dysfunction / diagnostic imaging*
  • Cognitive Dysfunction / psychology
  • Epilepsy / diagnostic imaging*
  • Epilepsy / pathology
  • Female
  • Humans
  • Magnetic Resonance Imaging* / methods
  • Male
  • Thalamus / diagnostic imaging*