MRA of hemodialysis access grafts and fistulae using selective contrast injection and flow interruption.
MR is a potentially attractive modality for evaluating hemodialysis access anatomy and function. However, the wide range of flow rates in the hemodialysis access complicates interpretation of phase contrast, time-of-flight, and even contrast-enhanced MR angiograms. At high flow rates, signal voids may easily arise at mild narrowings or sharp-angled anastomoses. A method is proposed which visualizes hemodialysis accesses without flow artifacts. Diluted Gd-DTPA is hand-injected directly into the access, while a cuff is used to reduce and subsequently interrupt access flow. Filling of the access is monitored using a fast projection technique with complex subtraction. When filling is satisfactory, a 3D acquisition is started. The feasibility of this selective contrast-enhanced MR angiography technique is demonstrated in four Cimino-fistulae and four PTFE grafts. Magn Reson Med 45:557-561, 2001.
Bos
C
C
Department of Radiology, Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands. clemens@isi.uu.nl
Smits
J H
JH
Zijlstra
J J
JJ
van Der Mark
W A
WA
Blankestijn
P J
PJ
Bakker
C J
CJ
Viergever
M A
MA
Mali
W P
WP
D001166:Arteriovenous Shunt, Surgical; D016477:Artifacts; D003287:Contrast Media / Q000008:administration & dosage*; D019786:Gadolinium DTPA; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods*; D006435:Renal Dialysis
D003287:Contrast Media; D019786:Gadolinium DTPA