Establish New Formulas for the Calculation of Renal Depth in Both XXXX and Adults.

@entity1 @entity8
OBJECTIVE: This study was performed to develop a new formula to estimate the @entity8 in both @entity1 and adults; then compare the new formula with previously published formulas. METHODS: Renal depth and total thickness (T, cm) of the body at the level of the kidneys were measured by CT in 113 @entity1 and 246 adults. Their sex, age, height (H, cm), and weight (W, kg) were recorded. Multiple stepwise linear regression analysis were conducted, using data from @entity1 and adults together. The 359 cases were divided into 2 random groups, of which, the first group was used to derive a regressive formula, and the second was used to verify the formula and compare the formula with previously published formulas in different groups. RESULTS: Multiple stepwise linear regression analysis showed that the important variable in estimating the depth of each kidney was the ratio of body weight (W, kg) to body height (H, cm) and the total thickness (T, cm) of the body at the level of the kidneys. The new formula was as follows: for right @entity8 (cm) = 0.22 * T + 7.714 * W/H-0.331 (r = 0.95), and for @entity8 (cm) = 0.238 * T + 6.553 * W/H-0.618 (r = 0.95). It is better than the other four formulas in different groups, especially in @entity1 and W/H  <= 0.30 (in adults) groups. CONCLUSIONS: We first introduced T into @entity8 estimation formula and established the new formula. It has a better performance than the other four formulas in different groups. The new formula provided reliable and accurate @entity8 and may contribute to improving the methods used to estimate renal function from radionuclide renography.
