Mitra S C, Venkataseshan V S, von Hagen S, Barton P T, Delshad G, Gil J
Department of Obstetrics and Gynecology, Jamaica Hospital, New York, USA.
Obstet Gynecol. 1997 Feb;89(2):238-41. doi: 10.1016/S0029-7844(96)00501-7.
To determine the changes in the vessel-wall thickness and the radius of the lumen in tertiary-stem villi of the placenta with advancing gestational duration and their relationship to umbilical artery Doppler flow studies.
Placentas from 63 miscarriages and preterm and term deliveries (between 19 and 40 weeks) were used for morphometric study of the tertiary-stem villi vessels. Each woman had undergone Doppler flow study of the umbilical artery. The resistance index (RI) was determined from the Doppler flow velocity waveform. Placental paraffin sections of 4-micron thickness were stained with hematoxylin and eosin and with periodic acid-Schiff reagents. The tertiary-stem villi and their vessels were examined microscopically and assessed morphometrically using a personal computer with math co-processor and a touch-sensitive screen overlying a video monitor. The monitor received microscopic images from a video camera that was mounted on a microscope. We determined vessel-wall thickness by tracing the outer and inner circumferences of digitized vessel-wall images.
Wall thickness, but not lumen size, of the tertiary-stem villi vessels decreased significantly overall at a rate of 0.63micron/week (P < .001). The rate of decrease was 0.64micron/week (P < .001) during the second trimester and 0.50micron/week (P < .001) during the third trimester. There was a significant correlation between the decrease in thickness and in RI (r = 0.83 [P < .001], r = 0.78 [P < .001] in the second and third trimesters, respectively). Resistance indices were all within normal limits.
Placental tertiary-stem villi vessel-wall thickness decreases with advancing gestational age. There is a correlation between the changes in RI of the umbilical artery Doppler flow and the changes in mean wall thickness of the placental vessels.
确定随着孕周增加胎盘三级绒毛干血管壁厚度和管腔半径的变化及其与脐动脉多普勒血流研究的关系。
选取63例流产、早产及足月分娩（孕周在19至40周之间）的胎盘用于三级绒毛干血管的形态计量学研究。每位孕妇均接受了脐动脉多普勒血流研究。根据多普勒血流速度波形确定阻力指数（RI）。将4微米厚的胎盘石蜡切片用苏木精和伊红以及过碘酸希夫试剂染色。在配备数学协处理器和覆盖视频监视器的触摸屏的个人计算机上，对三级绒毛干及其血管进行显微镜检查并进行形态计量学评估。监视器接收安装在显微镜上的摄像机拍摄的显微图像。通过描绘数字化血管壁图像的外周和内周来确定血管壁厚度。
三级绒毛干血管壁厚度总体上以0.63微米/周的速率显著降低（P <.001），而管腔大小无明显变化。孕中期降低速率为0.64微米/周（P <.001），孕晚期为0.50微米/周（P <.001）。厚度降低与RI降低之间存在显著相关性（孕中期r = 0.83 [P <.001]，孕晚期r = 0.78 [P <.001]）。阻力指数均在正常范围内。
胎盘三级绒毛干血管壁厚度随孕周增加而降低。脐动脉多普勒血流RI的变化与胎盘血管平均壁厚度的变化之间存在相关性。
