title: Embryology of neural tube defects: information provided by associated malformations.
abstract: OBJECTIVE
  To get information about embryologic mechanisms of neural tube defects (NTD), by studying the associated malformations.
  
  
  METHODS
  Eighty three cases of NTD, seen at the prenatal diagnosis unit of Rennes University Hospital (France) between May 1999 and December 2002, were retrospectively studied. Cases with chromosomal anomalies (5/83), cases without available karyotype or pathologic examination were excluded. 24 spina bifida, and 27 cephalic forms (anencephalies, exencephalies, and encephaloceles) were thus analyzed.
  
  
  RESULTS
  Only 22/51 cases (43%) were strictly isolated NTD. Anomalies of tissues arising from neural crests were noted in 8/51 fetuses (16%), midline or lateralization anomalies in 12/51 (24%), and anomalies of mesoblastic tissues in 17/51 (33%). An already known syndrome was found in 4/51 cases (8%).
  
  
  CONCLUSIONS
  NDT are more extensive congenital damages that would suggest the restrictive terminology. That prompts to assess cautiously prenatal diagnosis of NTD, and to get detailed pathological examination after termination of pregnancy.
authors.affiliation: Department of obstetrics and gynecology, University Hospital, Rennes, France. ascabaret@yahoo.fr
authors.forename: A S
authors.initials: AS
authors.lastname: Cabaret
authors.forename: P
authors.initials: P
authors.lastname: Loget
authors.forename: L
authors.initials: L
authors.lastname: Loeuillet
authors.forename: S
authors.initials: S
authors.lastname: Odent
authors.forename: P
authors.initials: P
authors.lastname: Poulain
mesh_terms: D000015:Abnormalities, Multiple / Q000196:embryology* / Q000473:pathology; D000328:Adult; D000757:Anencephaly / Q000196:embryology / Q000473:pathology; D005260:Female; D006801:Humans; D009436:Neural Tube Defects / Q000196:embryology* / Q000473:pathology; D011247:Pregnancy; D011296:Prenatal Diagnosis; D012189:Retrospective Studies; D016135:Spinal Dysraphism / Q000196:embryology / Q000473:pathology