title: Lateral ventricles in fetuses with aneuploidies at 11-13 weeks' gestation.
abstract: OBJECTIVE
  To examine the possible association between aneuploidies and fetal lateral cerebral ventriculomegaly in the first trimester of pregnancy.
  
  
  METHODS
  Three-dimensional brain volumes were acquired by transvaginal ultrasound examination at 11-13 weeks' gestation in 410 euploid fetuses and 63 fetuses with trisomy 21, 34 with trisomy 18 and seven with trisomy 13. Lateral ventricles were assessed in a transverse view, just above the roof of the third ventricle and measurements of the areas of the lateral ventricles and choroid plexuses were obtained. The ratio between choroid plexus and lateral ventricle areas (CLR) was calculated. Measurements in aneuploid fetuses were compared to those in euploid fetuses.
  
  
  RESULTS
  In euploid fetuses the lateral ventricle and choroid plexus areas increased, whereas the CLR decreased with fetal biparietal diameter. In fetuses with trisomy 21, lateral ventricle and choroid plexus areas were smaller but CLR was not significantly different from that in euploid fetuses. In trisomy 18 and 13 fetuses, CLR was significantly smaller than in euploid fetuses. The CLR was below the 5(th) centile of normal range in 11 (32.4%) fetuses with trisomy 18 and in six (85.7%) with trisomy 13.
  
  
  CONCLUSIONS
  There is evidence of ventriculomegaly at 11-13 weeks' gestation in most fetuses with trisomy 13 and one third of fetuses with trisomy 18.
authors.affiliation: Department of Obstetrics and Gynecology, S. João Hospital, Medical School, University of Porto, Porto, Portugal. tereloureiro@yahoo.com.br
authors.forename: T
authors.initials: T
authors.lastname: Loureiro
authors.forename: F
authors.initials: F
authors.lastname: Ushakov
authors.forename: N
authors.initials: N
authors.lastname: Maiz
authors.forename: N
authors.initials: N
authors.lastname: Montenegro
authors.forename: K H
authors.initials: KH
authors.lastname: Nicolaides
mesh_terms: D000328:Adult; D000782:Aneuploidy; D002831:Choroid Plexus; D025063:Chromosome Disorders / Q000000981:diagnostic imaging*; D002882:Chromosomes, Human, Pair 13 / Q000000981:diagnostic imaging; D002887:Chromosomes, Human, Pair 18; D004314:Down Syndrome / Q000000981:diagnostic imaging; D005260:Female; D005333:Fetus; D005865:Gestational Age; D006801:Humans; D006849:Hydrocephalus / Q000000981:diagnostic imaging* / Q000235:genetics; D020547:Lateral Ventricles / Q000002:abnormalities* / Q000000981:diagnostic imaging; D008875:Middle Aged; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D014314:Trisomy; D000073839:Trisomy 13 Syndrome; D016216:Ultrasonography, Prenatal / Q000379:methods*; D055815:Young Adult