RADIOISOTOPE RENOGRAPHY IN CHILDREN. I. THE RENOGRAM IN CHILDREN WITHOUT RENAL DISEASE

Isotope renograms (ortho-iodohippurate-I were obtained from 30 children who had no evidence of renal disease. Determinations were made by a standardized technique with the subjects in a state of relative dehydration; in 15 children the renogram was repeated under conditions of hydration (14 children) or further dehydration (1 child). Values for the point of initial peak (point A), point of maximal radioactivity (point B), and the differences between these points (B-A) were calculated. These values were plotted arithmetically against surface area to obtain regression lines and estimates of the variability of the observations about the line. The time from appearance of radioactivity to peak radioactivity was calculated and found to fall into a relatively narrow range. Similar attempts to correlate mathematically the height of timed segments of the decreasing slope of the renogram with surface area were successful in children with a body surface area of 1.15 m2 or greater. The state of hydration appeared to influence the excretory slope of the renogram; this effect was most pronounced in children whose total body surface area was less than 1.15 m2.