[Sequence-CT: early enhancement--curves of the healthy kidney]

Ten healthy kidneys were studied by sequence-scans every 15 seconds following i. v. bolus-injection of metrizoate. Enhancement of renal cortex, medulla and the abdominal aorta was measured separately. The curves of the renal parenchyma are summations of three functions: perfusion, diffusion of contrast agent to the interstitial fluid, and accumulation of the enhanced urine and its excretion. The enhancement-curves of the aorta and of the renal cortex show two peaks due to recirculation and high perfusion. The curve of the renal medulla is characterized by a slow rise and lower and wider single peak. Knowledge of the normal enhancement-curves is essential for the evaluation of altered renal perfusion.