OBJECTIVE: To estimate the in vivo dimensions of the fetal villous tree of the normal term placenta. METHODS: Dual-circuit perfusion-fixation of a cotyledon from eight normal term placentas was performed with random intra-cotyledon tissue sampling. Stereologic methods were used to derive estimates of villous (intermediate and terminal) surface area and volume, and star volume (a measure of villous volume). RESULTS: Villous surface area (mean 20.9 m2 [standard deviation 1.8]), capillary surface area (12.8 m2 [1.5]), villous volume (469 mL [40]), and capillary volume (80 mL [10]) values were all approximately 50% higher than reported previously. Star volume estimates ranged from 480 to 1350 microns 3. CONCLUSION: Tissue perfusion-fixation more accurately reconstructs the in vivo state, resulting in higher reference values than previously thought for the fetal villous tree dimensions. Up to one-quarter of fetoplacental blood volume is likely to be accommodated within the placenta at term.
OBJECTIVE: To estimate the in vivo dimensions of the fetal villous tree of the normal term placenta. METHODS: Dual-circuit perfusion-fixation of a cotyledon from eight normal term placentas was performed with random intra-cotyledon tissue sampling. Stereologic methods were used to derive estimates of villous (intermediate and terminal) surface area and volume, and star volume (a measure of villous volume). RESULTS: Villous surface area (mean 20.9 m2 [standard deviation 1.8]), capillary surface area (12.8 m2 [1.5]), villous volume (469 mL [40]), and capillary volume (80 mL [10]) values were all approximately 50% higher than reported previously. Star volume estimates ranged from 480 to 1350 microns 3. CONCLUSION: Tissue perfusion-fixation more accurately reconstructs the in vivo state, resulting in higher reference values than previously thought for the fetal villous tree dimensions. Up to one-quarter of fetoplacental blood volume is likely to be accommodated within the placenta at term.
Authors: Terry K Morgan; Jorge E Tolosa; Lisa Mele; Ronald J Wapner; Catherine Y Spong; Yoram Sorokin; Donald J Dudley; Alan M Peaceman; Brian M Mercer; John M Thorp; Mary Jo O'Sullivan; Susan M Ramin; Dwight J Rouse; Baha Sibai Journal: J Matern Fetal Neonatal Med Date: 2012-12-12
Authors: Gareth A Nye; Emma Ingram; Edward D Johnstone; Oliver E Jensen; Henning Schneider; Rohan M Lewis; Igor L Chernyavsky; Paul Brownbill Journal: J Physiol Date: 2018-02-25 Impact factor: 5.182