[Experimental study of flow rates in microcatheters using various kinds of contrast materials: comparison of imaging capability by iodine delivery rates].

In order to establish the optimal injection technique for abdominal digital subtraction angiography (DSA), flow rate measurement was performed under various combinations of all the currently available iodinated contrast materials with two types of coaxial microcatheters. In vitro study was done utilizing a plastic model of the abdominal aorta with the tip of the catheter positioned at the presumed proper hepatic artery. A total of 20ml of contrast material was injected by a pressure injector at a rate of 3 ml/sec at 300 or 600 psi, and actual flow volume was measured. Imaging capability was evaluated by calculating iodine delivery rates (IDRs). IDRs were highest in iopamidol 300 mgI/ml and iomeperol 300 mgI/ml, nonionic monomeric contrast materials of medium concentration. The results suggest that the best quality DSA images with injection to the proper hepatic artery using a coaxial microcatheter can be obtained with nonionic monomeric contrast materials of medium concentration.