title: Comparison of Doppler parameters of central versus intraparenchymal renal arteries in physiologically normal newborns.
abstract: BACKGROUND
  Changes in renal arterial Doppler flow may identify parenchymal disease, but in newborns knowledge of normal physiological parameters is a prerequisite for correct interpretation.
  
  
  OBJECTIVE
  To evaluate renal blood flow in healthy newborns by means of Doppler US.
  
  
  METHODS
  On the fourth day of life we examined 100 normal term newborn infants (200 kidneys). Blood flow in the central renal arteries was compared with that in the intraparenchymal arteries. Maximum systolic velocity ( V(max)), end-diastolic velocity ( V(ed)), mean flow velocity ( V(mean)), resistive index (RI) and pulsatility index (PI) were assessed.
  
  
  RESULTS
  All parameters were significantly higher in the central renal arteries than in the intraparenchymal arteries (RI 0.78+/-0.07 vs 0.62+/-0.05, P<0.0001; PI 1.84+/-0.52 vs 1.09+/-0.18, P<0.0001).
  
  
  CONCLUSIONS
  Physiological data are presented that are necessary for the correct interpretation of neonatal Doppler US.
authors.affiliation: Neonatology Clinic, Jessenius Faculty of Medicine, Kollarova 2, 036 59 Martin, Slovak Republic. stavel@lefa.sk
authors.forename: Miroslav
authors.initials: M
authors.lastname: Stavel
authors.forename: Mirko
authors.initials: M
authors.lastname: Zibolen
authors.forename: Hana
authors.initials: H
authors.lastname: Kolarovszka
authors.forename: Dalibor
authors.initials: D
authors.lastname: Murgas
mesh_terms: D001783:Blood Flow Velocity; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D012016:Reference Values; D012077:Renal Artery / Q000000981:diagnostic imaging* / Q000502:physiology; D012079:Renal Circulation / Q000502:physiology*; D018608:Ultrasonography, Doppler; D014655:Vascular Resistance