Radioactive isotope renography has been a useful clinical procedure but, with only qualitative interpretation of the renogram, it is subject to diagnostic error. A statistical analysis of an approach to quantitation using the criteria of Tmax and T½ has been performed. With upper limits of normal set at 4 min and 7 min, respectively, for these criteria, 2 of 22 normal subjects showed false-positive results and 18 of 114 patients with proved renal disease had false-negative results. The analysis indicated that this simple and rapid quantitative approach led to a reasonable degree of accuracy.
Brown FA, Gelber RH, Youkeles LH, Bennett LR. Quantitative Approach to the I131 Renogram. JAMA. 1963;186(3):211–214. doi:10.1001/jama.1963.03710030051008