The aim of the study was to determine if the fetal basilar artery demonstrated flow redistribution in the presence of fetal hypoxia in the same manner as has been demonstrated in the middle cerebral artery. 252 measurements of the fetal basilar artery pulsatility index were recorded from appropriately grown fetuses with normal umbilical and middle cerebral artery Doppler measurements between 27 and 40 weeks gestation. From these a nomogram with a 90% reference interval was constructed. The fetal basilar artery pulsatility index was also measured in 14 fetuses with intrauterine growth restriction that showed evidence of the 'brain-sparing effect' via a low middle cerebral artery pulsatility index. These values, when plotted on the basilar artery nomogram, were uniformly reduced from the expected values for gestational age in a similar distribution to the middle cerebral artery pulsatility index values. This indicates reduced vascular impedance in the fetal basilar artery in the presence of hypoxia. Doppler measurement of the fetal basilar artery can be used to demonstrate the 'brain-sparing effect' and can be particularly useful in the situation of a persistently face-down fetus when spectral Doppler trace of the middle cerebral artery cannot be achieved.
|Number of pages||5|
|Publication status||Published - 2008|