[Quantitative analysis of the development and age-related anatomy of the inferior vena cava in human ontogeny]

Periods of intensive changes and phases of a relative stabilization are observed in the inferior vena cava development. By the 4th month of the prenatal period of ontogenesis the inferior vena cava is completely formed and further its general plan of development has no any principle differences. In fetuses and children there is an essential increase of the lumen, length and angle in the inferior vena cava formation. An intensive growth of the transversal section area of the inferior vena cava initial portion in infants is connected with transition to vertical position and an increasing hydrodynamic loading in the mentineed portio of the inferior vena cava. In fetuses, newborns and children up to 12 years of age the inferior vena cava has a high level of formation, that corresponds to position of III--IV lumbar vertebrae. A statistically significant increase in the inferior vena cava parameters is noted in the adolescent period, which result from a general intensive development of the human organism ad its vascular system, in particular. At this age the level of the inferior vena cava formation descends up to the area of the IV--V lumbar vertebrae. Intensive changes in the inferior vena cava size is completed by the end sexual maturation. In the first and second mature ages a phase of a relative stabilization in the inferior vena cava development is noted. In elderly and old ages certain vasodilatation and elongation of the inferior vena cava is observed. Its formation area descends to the level of V lumbar -- I sacral vertebrae. Correlative analysis has proved the main stages in the development of the vessel studied, and the regression equations obtained can be used as an additional method for defining age of the corpse when a forensic medical examination is performed.