title: The dynamic fetal brain.
abstract: OBJECTIVE
  To evaluate fetuses with normal intracranial anatomy in the second trimester that became abnormal in the third trimester.
  
  
  METHODS
  We sonographically examined 6 fetuses with a normal second-trimester head sonogram that presented later in pregnancy with an abnormal head sonogram.
  
  
  RESULTS
  Four categories of intracranial pathology were depicted: obstructive hydrocephalus, intraventricular intracranial hemorrhage, non-intraventricular intracranial hemorrhage, and porencephaly.
  
  
  CONCLUSIONS
  Despite a normal midtrimester intracranial examination, evaluation of the fetal intracranial contents should be undertaken in subsequent sonographic examinations, because significant pathology can develop spontaneously.
authors.affiliation: Department of OB/GYN, University of California Davis Medical Center, 4860 Y Street, Sacramento, CA 95817, USA.
authors.forename: Dena
authors.initials: D
authors.lastname: Towner
authors.forename: John
authors.initials: J
authors.lastname: McGahan
authors.forename: Laila
authors.initials: L
authors.lastname: Rhee-Morris
authors.forename: Eugenio
authors.initials: E
authors.lastname: Gerscovich
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000002:abnormalities* / Q000473:pathology; D002535:Cerebral Aqueduct / Q000000981:diagnostic imaging / Q000473:pathology; D002543:Cerebral Hemorrhage / Q000000981:diagnostic imaging*; D003251:Constriction, Pathologic / Q000000981:diagnostic imaging / Q000473:pathology; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D005865:Gestational Age; D006801:Humans; D009421:Nervous System Malformations / Q000000981:diagnostic imaging*; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011263:Pregnancy Trimester, Third; D012016:Reference Values; D016216:Ultrasonography, Prenatal