title: Network specific change in white matter integrity in mesial temporal lobe epilepsy.
abstract: OBJECTIVE
  To identify the specific change of white matter integrity that occurs in the brain network related to epileptic activity in patients with mesial temporal lobe epilepsy (MTLE).
  
  
  METHODS
  We recruited 18 patients with MTLE and 18 healthy subjects. In MTLE patients, the remote functional-deficit zone was delineated using fluorodeoxyglucose positron emission tomography as an extratemporal region showing glucose hypometabolism. Using diffusion magnetic resonance imaging tractography, we defined a seizure propagation tract (PT) as a white matter pathway that connects the focus with a remote functional deficit zone. We also used the corticospinal tract (CST) and inferior longitudinal fasciculus (ILF) as control tracts in the hemisphere ipsilateral to the focus. Fractional anisotropy (FA), mean diffusivity (MD), and volume of the tracts were compared among PT, CST, and ILF.
  
  
  RESULTS
  Tractographic analysis identified the uncinate fasciculus, arcuate fasciculus, and fornix as PTs. A decrease in FA was found in MTLE patients compared with healthy subjects in all tracts, but PTs showed a more significant decrease in FA than did the two control tracts. Although the change in MD was also found in MTLE patients compared with healthy controls, a tract-specific change was not observed. Although white-matter damage was observed in all candidate tracts examined, the integrity of white matter was most significantly decreased in PTs in MTLE.
  
  
  CONCLUSIONS
  The change in white matter integrity occurs specifically in the pathways that connect the focus and remote functional deficit zones in patients with MTLE, i.e., the pathways that are assume to be associated with seizure propagation.
authors.affiliation: Department of Neurology, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: imamurah@kuhp.kyoto-u.ac.jp.
authors.forename: Hisaji
authors.initials: H
authors.lastname: Imamura
authors.affiliation: Department of Epilepsy, Movement Disorders and Physiology, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: matsumot@kuhp.kyoto-u.ac.jp.
authors.forename: Riki
authors.initials: R
authors.lastname: Matsumoto
authors.affiliation: Human Brain Research Center, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan; Radioisotope Research Center, Kyoto University, Kyoto 606-8315, Japan; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129, USA. Electronic address: shig.t@kuhp.kyoto-u.ac.jp.
authors.forename: Shigetoshi
authors.initials: S
authors.lastname: Takaya
authors.affiliation: Department of Neurology, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: tnakaga@kuhp.kyoto-u.ac.jp.
authors.forename: Tomokazu
authors.initials: T
authors.lastname: Nakagawa
authors.affiliation: Department of Neurology, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: smtk@kuhp.kyoto-u.ac.jp.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Shimotake
authors.affiliation: Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: tkik@kuhp.kyoto-u.ac.jp.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Kikuchi
authors.affiliation: Department of Neurology, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: sawa@kuhp.kyoto-u.ac.jp.
authors.forename: Nobukatsu
authors.initials: N
authors.lastname: Sawamoto
authors.affiliation: Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: kuny@kuhp.kyoto-u.ac.jp.
authors.forename: Takeharu
authors.initials: T
authors.lastname: Kunieda
authors.affiliation: Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan; Department of Neurosurgery, Sapporo Medical University, S1 W17, Chuo-ku, Sapporo 060-8556, Japan. Electronic address: mikunin@sapmed.ac.jp.
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Mikuni
authors.affiliation: Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: miy@kuhp.kyoto-u.ac.jp.
authors.forename: Susumu
authors.initials: S
authors.lastname: Miyamoto
authors.affiliation: Human Brain Research Center, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: fukuyama@kuhp.kyoto-u.ac.jp.
authors.forename: Hidenao
authors.initials: H
authors.lastname: Fukuyama
authors.affiliation: Department of Neurology, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: ryosuket@kuhp.kyoto-u.ac.jp.
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Takahashi
authors.affiliation: Department of Epilepsy, Movement Disorders and Physiology, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: akio@kuhp.kyoto-u.ac.jp.
authors.forename: Akio
authors.initials: A
authors.lastname: Ikeda
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology*; D038524:Diffusion Magnetic Resonance Imaging; D004833:Epilepsy, Temporal Lobe / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology*; D005260:Female; D019788:Fluorodeoxyglucose F18; D005947:Glucose / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D009434:Neural Pathways / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D012640:Seizures / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology; D066127:White Matter / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology*; D055815:Young Adult
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D005947:Glucose
keywords: Diffusion tractography; Epileptic activity; FDG-PET; Mesial temporal lobe epilepsy; Seizure propagation