title: Low-grade intraventricular hemorrhage disrupts cerebellar white matter in preterm infants: evidence from diffusion tensor imaging.
abstract: BACKGROUND
  Recent diffusion tensor imaging (DTI) studies have demonstrated that leakage of hemosiderin into cerebrospinal fluid (CSF), which is caused by high-grade intraventricular hemorrhage (IVH), can affect cerebellar development in preterm born infants. However, a direct effect of low-grade IVH on cerebellar development is unknown. Thus, we evaluated the cerebellar and cerebral white matter (WM) of preterm infants with low-grade IVH.
  
  
  METHODS
  Using DTI tractography performed at term-equivalent age, we analyzed 42 infants who were born less than 30 weeks gestational age (GA) at birth (22 with low-grade IVH, 20 without). These infants were divided into two birth groups depending on GA, and we then compared the presence and absence of IVH which was diagnosed by cerebral ultrasound (CUS) within 10 days after birth or conventional magnetic resonance imaging (MRI) at term-equivalent age in each group. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) at the superior cerebellar peduncle (SCP), middle cerebellar peduncle (MCP), motor tract, and sensory tract were measured.
  
  
  RESULTS
  In the SCP, preterm born infants with IVH had lower FA values compared with infants without IVH. In particular, younger preterm birth with IVH had lower FA values in the SCP and motor tract and higher ADC values in the MCP.
  
  
  CONCLUSIONS
  Low-grade IVH impaired cerebellar and cerebral WM, especially in the SCP. Moreover, younger preterm infants exhibited greater disruptions to cerebellar WM and the motor tract than infants of older preterm birth.
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.forename: Masafumi
authors.initials: M
authors.lastname: Morimoto
authors.forename: Kei
authors.initials: K
authors.lastname: Yamada
authors.forename: Tatsuji
authors.initials: T
authors.lastname: Hasegawa
authors.forename: Shigemi
authors.initials: S
authors.lastname: Morioka
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kidowaki
authors.forename: Masaharu
authors.initials: M
authors.lastname: Moroto
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yamashita
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Maeda
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Chiyonobu
authors.forename: Sachiko
authors.initials: S
authors.lastname: Tokuda
authors.forename: Hajime
authors.initials: H
authors.lastname: Hosoi
mesh_terms: D002531:Cerebellum / Q000473:pathology*; D002543:Cerebral Hemorrhage / Q000175:diagnosis*; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007235:Infant, Premature, Diseases / Q000175:diagnosis*; D008297:Male; D012720:Severity of Illness Index; D066127:White Matter / Q000473:pathology*