Determination of filtration fraction using the gamma scintillation camera

A simple technique for determining effective renal plasma flow, filtration fraction and filtration rate is described. The determination depends upon the use of 131iodine labeled hippuran and 99mtechnetium labeled iron ascorbate or Sn diethylenetriaminepentaacetic acid. The filtration fraction is determined by dividing the corrected uptake for the technetium compound by the corrected uptake for radiohippuran. The uptake is simply determined by the 1 to 2-minute count over the kidneys with background subtraction and taking into account the amount injected. The technique is simple, quick and appears to be a useful clinical tool.