الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 151 |  |  |
| | | from | 151 | | |
Abstract
Preeclampsia is a pregnancy specific syndrome of reduced organ perfusion secondary to vasospasm and endothelial activation. characterized by hypertension with proteinuria and/or oedema occuring in the second half of pregnancy presenting after 20 weeks of gestation in a previously healthy women. Some women may have atypical preeclampsia with all aspects of the syndrome, but without hypertension or proteinuria, or both.
The main pathologic feature of preeclampsia is vasospasm, which leads to impairment of blood flow to various organs particularly the uterus and placenta.
These placental blood flow abnormalities give rise to interference with fetal oxygenation and growth. It is now thought that uteroplacental ischaemia is responsible for preeclampsia.
Abnormal umbilical artery Doppler velocimetry was found to be associated with more frequent growth retardation and fetal distress. Angle-independent indices differ among the different cerebral arteries. The middle cerebral artery is the most studied cerebral artery because it is easy to sample; it provides information on the cerebral blood flow; and it can be sampled at an angle of 0° between the ultrasound beam and the direction of the blood flow. Therefore, for the middle cerebral artery, angle-independent indices (the most used is the pulsatility index) and the real velocity of blood flow are determined.