Kidney position and the measurement of relative uptake of 131-I Hippuran in renography.

The distribution of kidney position in the sitting posture has been determined in a series of patients presenting for renography, using radiographic and ultrasonic techniques. Both the craniocaudal distribution of kidney centre positions and the distribution of the differences in depth below the posterior skin surface of the two kidney centres have been found to have a significant standard deviation. The effect of these distributions on the measurement of relative effective renal plasma flow by 131-I Hippuran probe renography has been calculated for the situation in which no kidney localizing techniques are used. The resulting error distribution has an SD of 21.7 per cent in the case of equally divided function.