Decrease in pulsatile flow in the internal carotid artery in fetal hydrocephalus.

The effect of ventriculomegaly on pulsatile flow in the internal carotid arteries has been studied by Doppler ultrasound in four hydrocephalic fetuses. The pulsatility index showed progressive elevation proportional to the developing ventriculomegaly and thus may be a valuable index for the study of the mechanism of brain injury and for the determination of optimal timing of intervention.