title: Assessment of the posterior brain at 11-14 weeks for the prediction of open neural tube defects.
abstract: OBJECTIVE
  To evaluate the routine midsagittal view of the posterior brain at the 11-13 weeks' ultrasound examination, for predicting open neural tube defects.
  
  
  METHODS
  Posterior brain was examined midsagittally for normality of the four-line view (upper and lower border of the brain stem, the choroid plexus of the fourth ventricle and the occipital bone). Intracranial translucency and cisterna magna (CM) were measured.
  
  
  RESULTS
  The posterior brain was assessed in 1330 cases. The four-line view was normal in all but one case. In the two cases of open spina bifida contained in the study population, intracranial translucency was within normal range. The CM and the four-line view were normal in the first case, whereas in the second case, the four-line view was abnormal, and CM was obliterated and impossible to measure. No other cases of abnormal four-line view were observed in the study population.
  
  
  CONCLUSIONS
  Obliteration of the CM appears to be the most consistent early sign of open neural tube defects. Attention should focus on either measuring the cisterna magna or simply observing the presence of four lines in the midsagittal view of the posterior brain. However, these early signs of brain herniation are not present in all abnormal cases.
authors.affiliation: Department of Obstetrics and Gynecology, Rhodos General Hospital, Rhodes, Greece.
authors.forename: Ioannis
authors.initials: I
authors.lastname: Kavalakis
authors.forename: Athena P
authors.initials: AP
authors.lastname: Souka
authors.forename: Athanasios
authors.initials: A
authors.lastname: Pilalis
authors.forename: Ioannis
authors.initials: I
authors.lastname: Papastefanou
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Kassanos
mesh_terms: D001921:Brain / Q000196:embryology / Q000473:pathology; D002946:Cisterna Magna / Q000000981:diagnostic imaging; D018568:Crown-Rump Length; D004453:Echoencephalography / Q000379:methods; D005260:Female; D020546:Fourth Ventricle / Q000000981:diagnostic imaging; D005865:Gestational Age; D006801:Humans; D009436:Neural Tube Defects / Q000000981:diagnostic imaging*; D011247:Pregnancy; D011256:Pregnancy Outcome; D011261:Pregnancy Trimester, First / Q000502:physiology; D011379:Prognosis; D012189:Retrospective Studies; D016137:Spina Bifida Cystica / Q000000981:diagnostic imaging; D016216:Ultrasonography, Prenatal / Q000379:methods