TY - JOUR
T1 - Altered structural connectome in temporal lobe epilepsy
AU - DeSalvo, Matthew N
AU - Douw, Linda
AU - Tanaka, Naoaki
AU - Reinsberger, Claus
AU - Stufflebeam, Steven M
PY - 2014/3
Y1 - 2014/3
N2 - PURPOSE: To study differences in the whole-brain structural connectomes of patients with left temporal lobe epilepsy (TLE) and healthy control subjects.MATERIALS AND METHODS: This study was approved by the institutional review board, and all individuals gave signed informed consent. Sixty-direction diffusion-tensor imaging and magnetization-prepared rapid acquisition gradient-echo (MP-RAGE) magnetic resonance imaging volumes were analyzed in 24 patients with left TLE and in 24 healthy control subjects. MP-RAGE volumes were segmented into 1015 regions of interest (ROIs) spanning the entire brain. Deterministic white matter tractography was performed after voxelwise tensor calculation. Weighted structural connectivity matrices were generated by using the pairwise density of connecting fibers between ROIs. Graph theoretical measures of connectivity networks were compared between groups by using linear models with permutation testing.RESULTS: Patients with TLE had 22%-45% reduced (P < .01) distant connectivity in the medial orbitofrontal cortex, temporal cortex, posterior cingulate cortex, and precuneus, compared with that in healthy subjects. However, local connectivity, as measured by means of network efficiency, was increased by 85%-270% (P < .01) in the medial and lateral frontal cortices, insular cortex, posterior cingulate cortex, precuneus, and occipital cortex in patients with TLE as compared with healthy subjects.CONCLUSION: This study suggests that TLE involves altered structural connectivity in a network that reaches beyond the temporal lobe, especially in the default mode network.
AB - PURPOSE: To study differences in the whole-brain structural connectomes of patients with left temporal lobe epilepsy (TLE) and healthy control subjects.MATERIALS AND METHODS: This study was approved by the institutional review board, and all individuals gave signed informed consent. Sixty-direction diffusion-tensor imaging and magnetization-prepared rapid acquisition gradient-echo (MP-RAGE) magnetic resonance imaging volumes were analyzed in 24 patients with left TLE and in 24 healthy control subjects. MP-RAGE volumes were segmented into 1015 regions of interest (ROIs) spanning the entire brain. Deterministic white matter tractography was performed after voxelwise tensor calculation. Weighted structural connectivity matrices were generated by using the pairwise density of connecting fibers between ROIs. Graph theoretical measures of connectivity networks were compared between groups by using linear models with permutation testing.RESULTS: Patients with TLE had 22%-45% reduced (P < .01) distant connectivity in the medial orbitofrontal cortex, temporal cortex, posterior cingulate cortex, and precuneus, compared with that in healthy subjects. However, local connectivity, as measured by means of network efficiency, was increased by 85%-270% (P < .01) in the medial and lateral frontal cortices, insular cortex, posterior cingulate cortex, precuneus, and occipital cortex in patients with TLE as compared with healthy subjects.CONCLUSION: This study suggests that TLE involves altered structural connectivity in a network that reaches beyond the temporal lobe, especially in the default mode network.
KW - Adolescent
KW - Adult
KW - Algorithms
KW - Brain Mapping/methods
KW - Case-Control Studies
KW - Child
KW - Diffusion Tensor Imaging
KW - Electroencephalography
KW - Epilepsy, Temporal Lobe/pathology
KW - Humans
KW - Magnetic Resonance Imaging/methods
KW - Magnetoencephalography
KW - Middle Aged
KW - Positron-Emission Tomography
KW - Retrospective Studies
KW - Tomography, Emission-Computed, Single-Photon
U2 - 10.1148/radiol.13131044
DO - 10.1148/radiol.13131044
M3 - Article
C2 - 24475828
VL - 270
SP - 842
EP - 848
JO - Radiology Now
JF - Radiology Now
SN - 0033-8419
IS - 3
ER -