title: Sequential morphological change of Chiari malformation type II following surgical repair of myelomeningocele.
abstract: OBJECTIVE
  To document long-term morphological changes of Chiari type II malformation (CM-II) following closure of spina bifida manifesta (SBM).
  
  
  METHODS
  We retrospectively evaluated postnatal magnetic resonance images of the CM-II and posterior fossa (PF) in 28 consecutive cases. We measured changes in vertebral level and length of the cerebellar peg (CP), cerebrospinal fluid (CSF) spaces anterior and posterior to the cerebrospinal junction, PF area, and the anteroposterior diameters of the foramen magnum (FM) and C1 vertebra. We examined the morphological differences between the cases with and without ventriculoperitoneal (VP) shunting and derived predicted means by nonlinear mixed-effect modeling.
  
  
  RESULTS
  At birth, there were significant differences in CP length, PF area, and FM and C1 diameters between those who underwent VP shunting and those who did not. In cases with a CP below C1, VP shunting was required in every case but one. In those with visible CSF space at birth, VP shunts were not required. In 17 of 18 cases with a CP below C1, the vertebral level ascended by mean two vertebral levels (range 0-5 levels) within 4-6 months of delivery. In the remaining case, slowly progressive hydrocephalus and delayed CP descent required VP shunting at 8 months. Predicted mean CP length and FM and C1 diameters were greater in those who underwent VP shunting, but there was no difference in predicted mean PF area.
  
  
  CONCLUSIONS
  The morphology of CM-II and the presence of hydrocephalus influence each other in children who have undergone postnatal SBM repair.
authors.affiliation: Department of Neurosurgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan. khash@med.kyushu-u.ac.jp.
authors.forename: Kimiaki
authors.initials: K
authors.lastname: Hashiguchi
authors.affiliation: Department of Neurosurgery, Fukuoka Children's Hospital, Fukuoka, Japan.
authors.forename: Takato
authors.initials: T
authors.lastname: Morioka
authors.affiliation: Department of Neurosurgery, Iizuka Hospital, Iizuka, Japan.
authors.forename: Nobuya
authors.initials: N
authors.lastname: Murakami
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Togao
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Hiwatashi
authors.affiliation: Department of Pediatrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Ochiai
authors.affiliation: Data Center, Center for Clinical and Translational Research, Kyushu University, Fukuoka, Japan.
authors.forename: Goki
authors.initials: G
authors.lastname: Eriguchi
authors.affiliation: Department of Research and Development of Next Generation Medicine, Faculty of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Junji
authors.initials: J
authors.lastname: Kishimoto
authors.affiliation: Department of Neurosurgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Iihara
mesh_terms: D001139:Arnold-Chiari Malformation / Q000209:etiology* / Q000473:pathology*; D002531:Cerebellum / Q000473:pathology / Q000601:surgery; D015331:Cohort Studies; D003388:Cranial Fossa, Posterior; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging; D008297:Male; D008591:Meningomyelocele / Q000601:surgery*; D015233:Models, Statistical; D019635:Neurosurgical Procedures / Q000009:adverse effects*; D011183:Postoperative Complications / Q000503:physiopathology*; D012189:Retrospective Studies; D016137:Spina Bifida Cystica / Q000601:surgery
keywords: Hydrocephalus; MRI; Morphology; Myelomeningocele Chiari malformation