A simple catheter-vessel model for MR assessment of drug distribution in arteries and optimization of catheter design for intraarterial infusion therapy

Purpose: To investigate the efficacy of a new catheter-vessel model for MRI to evaluate drug distribution and to optimize catheter design for intraarterial infusion therapy Materials and Methods: The model consisted of a hepatic artery simulant tube through which blood simulant water flowed continuously and a water cistern. Catheters were inserted into the tube and a gadolinium contrast medium was injected at rates suitable for angiographic or computed tomographic evaluation and commensurate with the clinical drug infusion rate. Axial images of the tube were obtained with a 0.2-T scanner and gradient echo technique. Preliminary studies and catheter tests were conducted. The points at which drug and water were completely mixed were defined as the site with uniform enhancement nearest the catheter tip. Results: Flip angle and gadolinium concentrations were optimized at 90 degrees, and at 62.5 and 500 mM for the high and low infusion rates, respectively. Drug distribution near the catheter tips was clearly visualized. The drug was mixed in shorter distances via the slit side-hole than the end- or side-hole catheters, and the smaller diametrical than the larger at either rate. Conclusion: This model appeared to be effective for evaluation of drug distribution and optimization of catheter design.