title: Periventricular nodular heterotopia is related to severity of the hindbrain deformity in Chiari II malformation.
abstract: BACKGROUND
  Knowledge of the occurrence of malformations of cortical development (MCDs) and its relationship to hindbrain deformity in Chiari II malformation (CIIM) is limited.
  
  
  OBJECTIVE
  To assess malformations of cortical development and its relationship to hindbrain deformity regarding Chiari II malformation.
  
  
  METHODS
  Brain and cervical spinal MRI from 66 children (age range, 1-256 days; mean age, 22.3 days) with Chiari II malformation were retrospectively reviewed. If present, the type, number and location of malformations of cortical development were recorded. Hindbrain deformity was assessed for the level of the medullary kink, the descent of the pons and the shape of the fourth ventricle; these parameters were compared in children with and without malformations of cortical development.
  
  
  RESULTS
  Twenty children with malformations of cortical development were identified. Only periventricular nodular heterotopia was noted. The median level of the medullary kink was significantly lower in children with malformations of cortical development compared with children without it (P = 0.037). A low pontomesencephalic junction was identified more frequently in children with malformations of cortical development (65.0%), relative to children without malformations of cortical development (34.8%) (P = 0.045). The fourth ventricular shape was not significantly different in children with or without malformations of cortical development (P = 0.684).
  
  
  CONCLUSIONS
  Periventricular nodular heterotopia was seen in a relatively high proportion of children with Chiari II malformation, suggesting that it may be associated with severe hindbrain deformity.
authors.affiliation: Department of Radiology, Kanagawa Children's Medical Center, Yokohama, Japan.
authors.forename: Ayako
authors.initials: A
authors.lastname: Hino-Shishikura
authors.forename: Tetsu
authors.initials: T
authors.lastname: Niwa
authors.forename: Noriko
authors.initials: N
authors.lastname: Aida
authors.forename: Tetsuhiko
authors.initials: T
authors.lastname: Okabe
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Nagaoka
authors.forename: Jun
authors.initials: J
authors.lastname: Shibasaki
mesh_terms: D001139:Arnold-Chiari Malformation / Q000150:complications* / Q000473:pathology*; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D054091:Periventricular Nodular Heterotopia / Q000150:complications* / Q000473:pathology*; D012249:Rhombencephalon / Q000002:abnormalities*