title: Middle cerebral artery velocimetry: different clinical relevance depending on umbilical velocimetry.
abstract: OBJECTIVE
  To evaluate the role of cerebral velocimetry as a predictor of perinatal outcome in high-risk pregnancies.
  
  
  METHODS
  Middle cerebral artery pulsatility index was measured in 576 high-risk pregnancies undergoing umbilical velocimetry. The results of both tests were evaluated with respect to the birth of small for gestational age (SGA) infants and adverse perinatal outcome, defined as perinatal death, cesarean delivery for fetal distress, or low Apgar score.
  
  
  RESULTS
  Once umbilical velocimetry was taken into account, cerebral velocimetry did not improve the prediction of fetal growth restriction or adverse perinatal outcome. Neither test was able to predict adverse perinatal outcome in normally grown fetuses. As for SGA fetuses with adverse perinatal outcome, the simultaneous assessment of both umbilical and cerebral velocimetry did not improve diagnostic accuracy (kappa index 0.37 versus 0.41 for umbilical velocimetry only). However, within the group of high-risk pregnancies with abnormal umbilical velocimetry, the risk of being SGA and having an adverse perinatal outcome was doubled (relative risk 2.1, 95% confidence interval 1.1, 4.3) if cerebral velocimetry also was abnormal.
  
  
  CONCLUSIONS
  The routine use of cerebral velocimetry in high-risk pregnancies adds little information beyond that obtained from umbilical velocimetry; however, it is useful in predicting SGA infants with adverse perinatal outcome when umbilical velocimetry is abnormal.
authors.affiliation: Department of Gynecology and Obstetrics, University of Pisa, Italy.
authors.forename: F A
authors.initials: FA
authors.lastname: Strigini
authors.forename: G
authors.initials: G
authors.lastname: De Luca
authors.forename: G
authors.initials: G
authors.lastname: Lencioni
authors.forename: P
authors.initials: P
authors.lastname: Scida
authors.forename: G
authors.initials: G
authors.lastname: Giusti
authors.forename: A R
authors.initials: AR
authors.lastname: Genazzani
mesh_terms: D001783:Blood Flow Velocity; D002536:Cerebral Arteries / Q000000981:diagnostic imaging*; D003430:Cross-Sectional Studies; D005260:Female; D005317:Fetal Growth Retardation / Q000000981:diagnostic imaging*; D006801:Humans; D007236:Infant, Small for Gestational Age; D017078:Laser-Doppler Flowmetry / Q000592:standards*; D011247:Pregnancy; D011256:Pregnancy Outcome; D018566:Pregnancy, High-Risk; D011673:Pulsatile Flow; D015203:Reproducibility of Results; D012306:Risk; D012680:Sensitivity and Specificity; D016216:Ultrasonography, Prenatal / Q000592:standards*; D014469:Umbilical Arteries / Q000000981:diagnostic imaging*