This study will test how well a new contrast agent (dye) used in magnetic resonance imaging
(MRI) can help visualize totally blocked arteries that normally supply blood to the neck,
arms or legs. Currently used agents work well in visualizing normal or partly blocked
arteries (arteries that have some blood flowing through them), but only poorly in totally
blocked arteries. This study will see if a contrast agent called gadofosveset can better
brighten images of completely blocked arteries. Gadofosveset is approved in Europe for use in
MRI scans, but is still considered experimental in the United States.
People 18 years of age or older with known or suspected total blockage of an artery to the
neck, arm or leg may be eligible for this study.
Participants undergo MRI scanning with gadofosveset contrast dye. MRI uses a magnetic field
and radio waves to produce images of body tissues and organs. For this procedure, the subject
lies on a table that can slide in and out of the tubular scanner, wearing earplugs to muffle
loud noises that occur during the scanning process. The procedure lasts about 1.5 to 2 hours,
during which the subject may be asked to hold his or her breath several times for as long as
5 to 20 seconds. During the procedure, gadofosveset is injected and several kinds of MRI
pictures are taken to understand better how the new agent works. Subjects may be asked to
undergo a second scan using conventional MRI contrast dye