[Comparison of iopamidol 150 and 370 with the same iodine dosage (37 g) in urography]

Two different volumes of iopamidol (250 and 100 ml, respectively) containing 37.5 and 37 g of iodine in different concentrations (150 mgI/ml and 370 mgI/ml) were injected in the same time (10 minutes) with varying injection rates, to compare diagnostic effectiveness, image quality, distension of the collecting system, and influence of the better iodine concentration. Sixty patients of both sexes were randomly subdivided into two groups. Their renal function, blood pressure and pulse rate were normal. Their weight ranged 55-85 kg, not to change the distribution volume of the contrast medium. None of them had been given iodine compounds recently. Radiographs were taken 2, 5, 15, 25, and 30 minutes after the end of the injection. The image quality of nephrograms, pyelograms, bladder views and the degree of collecting system filling were evaluated by a blind study, using grading scores (0 to 3). In both groups image quality and degree of filling were satisfying; the volume of injected iopamidol had poor significance. The clinical findings confirm that, with a nonionic contrast medium, iodine concentration in the collecting system is the most important factor for image quality.