RT Book, Section
A1 Pooh, Ritsuko K.
A1 Degani, Shimon
A2 Timor-Tritsch, Ilan E.
A2 Monteagudo, Ana
A2 Pilu, Gianluigi
A2 Malinger, Gustavo
SR Print(0)
ID 1138380813
T1 FETAL CEREBRAL CIRCULATION
T2 Ultrasonography of the Prenatal Brain, 3e
YR 2017
FD 2017
PB McGraw-Hill Education
PP New York, NY
SN 9780071613064
LK obgyn.mhmedical.com/content.aspx?aid=1138380813
RD 2024/12/11
AB KEY  POINTSData  collected  from  Doppler  velocity  recordings  using  both  spectral  and  color  Doppler  mode  confirm  the  fundamental  aspects  of  the  fetoplacental  circulation.  Changes  in  placental  vascular  resistance,  cardiac  contractibility,  vessel  compliance,  and  blood  viscosity  alter  the  normal  dynamics  of  fetal  cerebral  circulation.Reference  values  have  been  established  for  the  main  cerebral  vessels.  During  the  last  trimester  of  normal  pregnancies,  the  values  of  Doppler  waveform  indices  decrease  in  all  main  cerebral  vessels.  After  birth,  vascular  resistance  decreases,  and  later  stabilizes.  Cerebral  autoregulation  persists  from  fetal  to  postnatal  life,  with  low  waveform  indices  in  cerebral  vessels  of  growth-retarded  fetuses  and  neonates.  The  low  indices  indicate  decreased  cerebrovascular  resistance,  representing  the  redistribution  of  flow,  or  the  brain-sparing  effect.Combined  parameters  recorded  from  different  vascular  beds  may  provide  support  for  the  diagnosis  of  significant  hemodynamic  changes  and  are  of  prognostic  value  in  predicting  fetal  outcome  such  as  fetal  IUFGR  and  Rh  disease.As  far  as  imaging  of  the  vascularization  (arterial  and  venous)  of  the  prenatal  brain,  it  should  be  clear  that  no  brain  scan  should  be  considered  complete  without  looking  at  its  main  vessels  or  at  least  at  the  pericallosal  artery  on  a  median  section.  Should  such  a  protocol  be  too  complicated  to  achieve  in  all  anomaly  scans,  it  is  important  to  scrutinize  brain  vascularization  in  each  and  every  case  of  suspected  brain  anomaly.Three-dimensional  power  Doppler  US  technology,  especially  combined  with  high-frequency  TVS,  as  described  in  this  and  other  chapters,  is  the  most  preferable  noninvasive  and  reproducible  imaging  method  to  be  used.  The  accurate  information  about  deviant  brain  vascularity  may  help  to  render  proper  obstetric,  neurologic,  and  neurosurgical  management.