Black blood magnetic resonance angiography with Dy-DTPA polymer: Effect onarterial intraluminal signal intensity, lumen diameter, and wall thickness

Four rabbits in which atherosclerotic disease was induced by diet and ballo on angioplasty underwent conventional angiography and MR angiography (MRA) using a black blood pulse sequence before and 10 minutes after the iv injec tion of a macromolecular contrast agent, NC 100283 (1.0 mmol/kg), a dyspros ium diethylenetriaminepentaacetic acid hexamethylenediamine copolymer (Dy-D TPA polymer), Intraluminal signal intensity, apparent wall thickness, and l umen size measurements of the aorta and proximal common iliac arteries on p recontrast MRA images were compared with postcontrast images, Aortic lumen diameter measurements on the precontrast and postcontrast MRA studies were compared with lumen diameters from conventional angiograms, Intraluminal si gnal intensity decreased on postcontrast MRA. images compared with precontr ast images, with an average loss of signal equal to 29% (P < .05), Apparent wall thickness decreased by 24% (P < .05), Lumen diameter and area were ge nerally larger (average of 15% and 33%, respectively) on postcontrast MRA i mages than on precontrast images, Aortic lumen diameter measurements from p ostcontrast MRA agreed closely (95% confidence interval of the mean differe nce was -.2 to .3 mm), and precontrast MRA images tended to underestimate a ortic lumen diameter (95% confidence interval of the mean difference was .3 to .8 mm) compared with conventional angiography. Postcontrast MRA with NC 100283, a macromolecular Dy-DTPA contrast agent, provides more accurate as sessment of aortic lumen diameter than precontrast MRA, using conventional angiography as the standard reference.