[Objectives] This study was conducted to better understand the characteristics of the fetal blood circulation. [Methods] The cardiac opening of the inferior vena cava was observed in goat fetuses. There are two cardia...[Objectives] This study was conducted to better understand the characteristics of the fetal blood circulation. [Methods] The cardiac opening of the inferior vena cava was observed in goat fetuses. There are two cardiac openings of the inferior vena cava, namely, the foramen ovale with the valves and the right atrium opening of the inferior vena cava. The blood from the inferior vena cava moves easily into the right atrium via the right atrium opening because the right atrium opening without the valves is located in the lower right of the foramen ovale, and is bigger than the interatrial foramen. [Results] The blood may flow into the left atrium through the foramen ovale when the blood volume into the right atrium exceeds the limit of the right atrium. The fetal inferior vena cava compared with after birth receives oxygenated blood in the umbilical vein from the placenta besides the normal blood. Accordingly the blood volume into the right atrium exceeds the limit of the right atrium. Extra oxygenated blood is diverted directly into the left atrium through the foramen ovale. [Conclusions] This study provides a reference for studying the blood circulation of fetuses and even adults.展开更多
The cerebral arterial circle (circle of Willis) plays an important role in the redistribution of the blood flow between the anterior and posterior territories and maintains the plasticity of the cerebral blood circula...The cerebral arterial circle (circle of Willis) plays an important role in the redistribution of the blood flow between the anterior and posterior territories and maintains the plasticity of the cerebral blood circulation. The anatomical variability of the vascular circle often alters the cerebral hemodynamics and determines the outcomes of acute and chronic cerebrovascular disease. The heritability and prevalence of certain variants of the circle of Willis in different ethnic and racial groups are frequently disputed by authors. Our cross-sectional retrospective study aims to compare the patterns of the cerebral arterial circle in 64 Caucasian cadavers with 64 Arabic living individuals, by methods of anatomic dissection and magnetic resonance angiography, respectively. The typical structure of the circle of Willis was revealed in 8.3% of the Caucasian study group, and in 22.2% of the Arabic one. The anterior part of the circle of Willis was incomplete in 6 out of 64 of the Caucasian specimens, where the anterior communicating artery was hypoplastic (6.3%) or absent (3.1%). The posterior part of the circle of Willis had hypoplastic or absent posterior communicating artery on one side in 20, and on both sides in 12 out of 64 Caucasian specimens. In the Arabic cohort, the posterior part of the circle of Willis was incomplete in 17 out of 64 specimens, with absence of the posterior communicating artery unilaterally (in 11 cases) or bilaterally (in 6 cases). The present study reveals that the configuration of the cerebral arterial circle and distribution of the blood flow between the anterior and posterior territories have certain differences in the Caucasian study group versus the Arabic one.展开更多
基金Supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)Scientific Research Fund of Nanjing General Hospital of Nanjing Military Command,China(2016033)
文摘[Objectives] This study was conducted to better understand the characteristics of the fetal blood circulation. [Methods] The cardiac opening of the inferior vena cava was observed in goat fetuses. There are two cardiac openings of the inferior vena cava, namely, the foramen ovale with the valves and the right atrium opening of the inferior vena cava. The blood from the inferior vena cava moves easily into the right atrium via the right atrium opening because the right atrium opening without the valves is located in the lower right of the foramen ovale, and is bigger than the interatrial foramen. [Results] The blood may flow into the left atrium through the foramen ovale when the blood volume into the right atrium exceeds the limit of the right atrium. The fetal inferior vena cava compared with after birth receives oxygenated blood in the umbilical vein from the placenta besides the normal blood. Accordingly the blood volume into the right atrium exceeds the limit of the right atrium. Extra oxygenated blood is diverted directly into the left atrium through the foramen ovale. [Conclusions] This study provides a reference for studying the blood circulation of fetuses and even adults.
文摘The cerebral arterial circle (circle of Willis) plays an important role in the redistribution of the blood flow between the anterior and posterior territories and maintains the plasticity of the cerebral blood circulation. The anatomical variability of the vascular circle often alters the cerebral hemodynamics and determines the outcomes of acute and chronic cerebrovascular disease. The heritability and prevalence of certain variants of the circle of Willis in different ethnic and racial groups are frequently disputed by authors. Our cross-sectional retrospective study aims to compare the patterns of the cerebral arterial circle in 64 Caucasian cadavers with 64 Arabic living individuals, by methods of anatomic dissection and magnetic resonance angiography, respectively. The typical structure of the circle of Willis was revealed in 8.3% of the Caucasian study group, and in 22.2% of the Arabic one. The anterior part of the circle of Willis was incomplete in 6 out of 64 of the Caucasian specimens, where the anterior communicating artery was hypoplastic (6.3%) or absent (3.1%). The posterior part of the circle of Willis had hypoplastic or absent posterior communicating artery on one side in 20, and on both sides in 12 out of 64 Caucasian specimens. In the Arabic cohort, the posterior part of the circle of Willis was incomplete in 17 out of 64 specimens, with absence of the posterior communicating artery unilaterally (in 11 cases) or bilaterally (in 6 cases). The present study reveals that the configuration of the cerebral arterial circle and distribution of the blood flow between the anterior and posterior territories have certain differences in the Caucasian study group versus the Arabic one.
