title: Longitudinal change in white matter in preterm infants without magnetic resonance imaging abnormalities: Assessment of serial diffusion tensor imaging and their relationship to neurodevelopmental outcomes.
abstract: OBJECTIVE
  We used diffusion tensor imaging (DTI) to evaluate longitudinal changes in fractional anisotropy (FA) of white matter tracts in preterm infants without abnormal magnetic resonance imaging (MRI) findings. Imaging was conducted at term equivalent age (TEA) and 1year of corrected age. Furthermore, we assessed correlations between FA and neurodevelopmental outcomes at 3years of corrected age to investigate brain prematurity of preterm infants without MRI abnormalities.
  
  
  METHODS
  Preterm infants underwent serial MRI at TEA and 1year of corrected age. Of these, 13 infants entered a retrospective study, undergoing neurodevelopmental assessment at 3years of corrected age. These infants were divided into two groups depending on gestational age (GA): <26weeks and ⩾26weeks. DTI-based tractography was performed to obtain the FA of the motor tract, sensory tract, superior cerebellar peduncle, middle cerebellar peduncle, and corpus callosum. FA was compared between two groups, and correlations between FA and neurodevelopmental outcomes were assessed.
  
  
  RESULTS
  FA of the splenium at TEA was significantly different between the two groups divided according to GA. However, this difference was no longer observed at 1year of corrected age. There was no correlation between FA of the splenium at TEA and neurodevelopmental assessment scores at 3years of corrected age.
  
  
  CONCLUSIONS
  At TEA, FA of the splenium was lower in younger GA infants without MRI abnormalities, but this may not affect subsequent neurodevelopmental outcomes.
authors.affiliation: Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kajii-cho Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kidowaki
authors.affiliation: Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kajii-cho Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan. Electronic address: morimoto@koto.kpu-m.ac.jp.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Morimoto
authors.affiliation: Department of Radiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Kei
authors.initials: K
authors.lastname: Yamada
authors.affiliation: Department of Radiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Sakai
authors.affiliation: Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kajii-cho Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Zuiki
authors.affiliation: Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kajii-cho Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Maeda
authors.affiliation: Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kajii-cho Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yamashita
authors.affiliation: Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kajii-cho Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Morita
authors.affiliation: Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kajii-cho Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.
authors.forename: Tatsuji
authors.initials: T
authors.lastname: Hasegawa
authors.affiliation: Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kajii-cho Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Chiyonobu
authors.affiliation: Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kajii-cho Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.
authors.forename: Sachiko
authors.initials: S
authors.lastname: Tokuda
authors.affiliation: Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kajii-cho Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Hosoi
mesh_terms: D001921:Brain / Q000000981:diagnostic imaging* / Q000254:growth & development*; D002657:Child Development; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D007223:Infant; D007234:Infant, Premature / Q000254:growth & development*; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D009434:Neural Pathways / Q000000981:diagnostic imaging / Q000254:growth & development; D066127:White Matter / Q000000981:diagnostic imaging* / Q000254:growth & development*
keywords: Diffusion tensor imaging (DTI); Fractional anisotropy (FA); Kyoto Scale of Psychological Development (KSPD); Splenium