Bilateral cingulum fiber reductions in temporal lobe epilepsy with unilateral hippocampal sclerosis

Eur J Radiol. 2017 Sep:94:53-57. doi: 10.1016/j.ejrad.2017.07.015. Epub 2017 Jul 23.


Purpose: To evaluate whether white matter tracts within the Papez circuit are altered in patients with unilateral hippocampal sclerosis (HS).

Methods: Twenty patients with histologically proven unilateral HS and 20 age-matched controls were studied with a 3T Epilepsy-dedicated MRI protocol including a MPRAGE sequence for hippocampus volumetry and a diffusion tensor imaging (DTI) sequence (61 diffusion-encoding directions, 2×2×2mm3 voxels) for diffusion tensor tractography (DTT). An energy-based global tracking algorithm was used to calculate streamline counts (SC) and fractional anisotropy (FA) of cingulate, fornix, and mammillo-thalamic tracts, respectively.

Results: Sclerotic hippocampi were significantly smaller compared to the contralateral side and to age-matched controls. Cingulum SC but not FA were reduced on the hippocampal sclerosis (258+81.0) and contralateral side (271+85.6) compared to age-matched controls (447+138).

Conclusion: Focusing on white matter tracts of the Papez circuit we showed that in patients with intractable temporal lobe epilepsy unilateral hippocampal sclerosis is associated with a bilateral reduction of cingulum association fibers projecting from the cingulate gyrus to the parahippocampal gyrus.

Keywords: Diffusiontensor imaging; Diffusiontensor tractography; Hippocampal sclerosis; MRI; Mesial temporal lobe epilepsy.

MeSH terms

  • Adult
  • Epilepsy, Temporal Lobe / diagnostic imaging*
  • Epilepsy, Temporal Lobe / pathology*
  • Female
  • Gyrus Cinguli / diagnostic imaging*
  • Gyrus Cinguli / pathology
  • Hippocampus / diagnostic imaging*
  • Hippocampus / pathology
  • Humans
  • Magnetic Resonance Imaging / methods*
  • Male
  • Sclerosis / diagnostic imaging
  • Sclerosis / pathology