Characterisation of deep arterio-venous anastomoses within monochorionic placentae by vascular casting
| Autor: | Myles J.O. Taylor, L. Y. Wee, N. Watkins, Nicholas M. Fisk, V. Franke, Kim H. Parker |
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| Rok vydání: | 2005 |
| Předmět: |
Adult
Acid digestion Placenta Biology Anastomosis Corrosion Casting Chorionic plate Pregnancy medicine Humans Arterio venous anastomoses Vein reproductive and urinary physiology Arteriovenous Anastomosis Laser treatment food and beverages Obstetrics and Gynecology Vascular casting Chorion Fetofetal Transfusion Twins Monozygotic Anatomy medicine.anatomical_structure Reproductive Medicine embryonic structures Female Developmental Biology Artery |
| Zdroj: | Placenta. 26:19-24 |
| ISSN: | 0143-4004 |
| DOI: | 10.1016/j.placenta.2004.04.007 |
| Popis: | Objective To characterise arterio-venous anastomoses (AVA) in monochorionic (MC) placentae and determine (i) whether shared cotyledons lie beneath the co-termination of an artery from one twin and a vein to the contralateral twin and (ii) whether all AVA can be detected by visual inspection of the chorionic plate. Methods Vascular casts were made of 15 MC placentae. The number of typical AVAs suspected visually before digestion was compared with the number of AVAs identified after acid digestion. Results Thirty-three of 67 (49%) suspected typical AVAs were confirmed as typical after casting. There were five false positives and no false negatives. The remainder were classified as atypical AVAs, found in ≥90% of MC placentae. Type I (small vascular connections between two apparently normal cotyledons not seen before casting) and Type II (shared cotyledons arising within larger apparently normal cotyledons) atypical AVAs were found in 53% and 73% of placentae, respectively. Conclusions Only half the shared cotyledons in MC placentae are characterised by co-termination of an artery and vein on the chorionic plate. We report the existence of deep anastomoses beneath the chorionic plate that cannot be visualised by chorionic plate inspection. These findings have implications for laser treatment of twin–twin transfusion syndrome. |
| Databáze: | OpenAIRE |
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