“…1,5 In these figures, the ejection volume was defined as the bottom of the downward trace caused by the tiptoe movement, while the residual volume was defined as the starting point of refilling, which corresponds to the bottom of the downward bowl-shaped trace following the tiptoe movement in the current study. In other reports 6,7 and the textbook, 4 however, the ejection volume and residual volume were both defined as the bottom of each trace caused by tiptoe movement(s). These differences would result in large differences in the parameters, as demonstrated in the current study, and affect the interpretation of venous hemodynamics.…”