PubMed · 13445885
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M E MARSHAK. 1957. [Flat thermoelectrode].. https://pubmed.ncbi.nlm.nih.gov/13445885/
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INTRODUCTION: Out of the three fetal circulatory shunts, namely the ductus venosus, the foramen ovale and the ductus arteriosus, the ductus venosus is the most important from the point of view of prenatal sonographic diagnosis. This short vessel channels blood from umbilical vein into the left atrium of the fetal heart. Thereafter, the blood, flowing through the left ventricle, supplies the myocardium and the central nervous system. AIM: The purpose of this investigation was to evaluate the feasibility of assessing fetal well being on the basis of sonographic measurement of the pulsatility index and the blood flow velocity waveforms. MATERIAL AND METHODS: Using color Doppler ultrasound instrument, in the course of routine antenatal examinations, the author investigated the blood flow velocity waveforms in the ductus venosus in 102 normal and 14 growth retarded fetuses. RESULTS: The blood flow velocity waveforms in the ductus venosus display two distinguishable peaks. The higher from them is seen during ventricular systole. The smaller peak reflects the blood flow during the passive filling caused by ventricular diastole and the ensuing minimal velocity, or perhaps a negative component with the next atrial contraction. CONCLUSIONS: Evaluation of the blood flow in the ductus venosus provides insight into physiologic and pathologic processes in the fetal organism. This technique is capable of identifying fetuses predisposed to or endangered by newborn diseases.
BACKGROUND: In head and neck reconstruction, the pectoralis major myocutaneous flap, located adjacent to the area of reconstruction, is a very useful and easy-to-prepare flap. However, it is reported to have an unstable blood circulation that could result in partial necrosis of the skin island. The current study investigated the detailed three-dimensional vascular network in the flap to establish a method of preparation with a stable circulation. METHODS: The pectoralis major muscle and the anterior chest skin on 12 sides of eight fresh cadavers were subjected to angiographic procedures in which contrast medium was injected selectively to the internal thoracic artery and the thoracoacromial artery. On another fresh cadaver, resin was injected in the same manner, and a clear specimen of the pectoralis major myocutaneous flap was prepared. RESULTS: The pectoralis major muscle consists of two anatomical vascular territories that the choke vessels in the muscle at the level of the fourth costal cartilage divide into cranial and caudal sides. The chest skin area on the caudal side where the skin island of the flap is prepared receives its blood supply from a dense anastomotic network formed by the fourth, fifth, and sixth intercostal perforating branches. CONCLUSIONS: The blood flow in the pectoral branch of the thoracoacromial artery runs through the choke vessels that dilate at the elevation of the pectoralis major myocutaneous flap, first into the fourth intercostal perforating branches; then to the anastomotic vascular network of the fourth, fifth, and sixth intercostal perforating branches; and finally to reach the periphery of the skin island.
The first known descriptions regarding the basic aspects of circulation was probably in 500 B.C., by the Greek thinker Alcmaeon of Croton who observed arteries and veins to be dissimilar in animal dissection, and this was followed by the description of the human heart as a three chambered organ by Aristotle in 350 B.C. Herophilus of Chalcedon, a Greek anatomist, confirmed the findings of dissimilarity between arteries and veins in human cadaver dissections in 300 B.C., and determines that arteries were thicker than veins and contained blood. The advancement by far in the learning of human circulation was made possible first by significant contribution of Galen followed by observations of Ibn al-Nafis, Servetus, Colombo, Cesalpino, Vesalius and Fabricius. In 17th century William Harvey, an English physician, made important advancements into the understanding of this important area of medicine, advancements that continued with the observations of Malpighi.