[Renal kinetics of contrast media in unilateral diseased kidney (author's transl)].

In order to utilize excretory urography for urological diagnosis as optimal as possible renal physiology and pathophysiology as well as urodynamics have to be fully considered. Experimental and clinical data of various degrees of bilateral renal insufficiency, unilateral renal impairment and unilateral hydronephrosis were used to compute plasma and urinary concentrations of contrast media in the diseased and contralateral kidney. The results can be summarized as follows: 1. In bilateral renal insufficiency without hydronephrosis delayed exposures do not improve the diagnostic findings. Increased administration of contrast media increases naturally the urinary concentration.--2. In unilateral renal impairment only high degrees of impairment are of clinical significance. The excretory urography therefore is not suitable for split function tests. In high degrees of impairment diagnostic results can be improved by delayed exposures up to 6 hours.--3. In general, delayed exposures improve the diagnostic results in hydronephrosis. In chronic hydronephrosis with high degrees of renal impairment the obstruction often can still be localized by use of continuous infusion urography. This investigation method is tolerated well, if the contraindications of highly osmotic substances and high fluid intake are considered.