Comparison of image quality and portal vein visualization in IADSP using iopamidol, 76% urografin, and 38% urografin.

The image quality of intra-arterial digital subtraction portography (IADSP) was studied in 50 randomly assigned patients using one of three contrast agents: iopamidol, (IOP, 20 cases), 76% Na-meglumine diatrizoate (76% UG, 20 cases), and 38% Na-meglumine diatrizoate (38% UG, 10 cases). Sharpness and contrast of images, and portal vein visualization were evaluated in these groups. IOP provided better image quality and portal vein visualization than 76% UG. There was no significant difference between them in terms of side effects, such as contrast medium-induced pain and feeling of warmth, or changes in physiological parameters like blood pressure and heart rate. When a low osmolar contrast agent like IOP passes through the mesentery capillary bed, the eflux of the contrast agent into the interstitial space and the influx of water into the capillary may be less, resulting in less dilution of the contrast agent in the superior mesenteric vein. This might explain the better image quality and portal vein visualization of IOP.