Figure 2: Changes of concentration and viscosity of solutions of six different contrast media (four LOCM depicted in blue: iopromide 300, iohexol 300, ioversol 300, and iomeprol 300; two IOCM depicted in red: iodixanol 320 and iosimenol 350) caused by in vitro dialysis to emulate the renal tubular concentration process. Iodine concentration (a) and viscosity (b) of the respective contrast agent solutions as marketed/formulated for clinical use (marked as CA) and after dialysis with PEG solutions with osmolalities of 290, 400, 500, 700, and 1000 mosm/kg H2O. Data are mean ± SEM. Please note that the viscosity of both IOCM solutions after the dialysis at 700 and 1000 mosm/kg H2O was so high that it even exceeded the upper measurement limit of the viscometer. Redrawn from data in [34].