Hemodialysis access fistula: MR angiography vs echo color Doppler evaluation

Purpose: To verify the diagnostic role of MRA in the evaluation of suspected stenosis in hemodialisys access fistula in the forearm, as the diagnostic tool of choice and an alternative to DSA in pre-surgical assessment. Material and Methods: 23 patients underwent MR examination of the autogenous hemodialysis fistula of the forearm, using a 1.5 T Unit (Philips Intera). The MR examination was performed using 3D PC technique before and after i.v. gadolinium administration, and 3D CE MR angiography, with a knee coil. All patient underwent dialysis after MR examination. Echo color Doppler examination was previously performed in all cases. The degree of stenosis was evaluated semi-quantitatively (3 point scale from 1=mild to 3=severe) by two blinded experts. Results: We observed a good correlation between MRA and echo color Doppler findings (R= 0.95). MRA showed in all cases the entire dialysis fistula, allowing an excellent morphological evaluation of the stenotic tract; in one case MRA showed an overestimation of the stenosis. CE-MRA was more useful than PC-MRA to evaluate smaller collateral vessels. Conclusion: CE-MRA provided a good evaluation of the hemodialysis fistula of the forearm and it provides a good alternative to DSA. It also gives useful information before percutaneous angioplasty or surgical revascularization procedure