Three-dimensional flow-independent peripheral angiography.
A magnetization-prepared sequence, T2-Prep-IR, exploits T1, T2, and chemical shift differences to suppress background tissues relative to arterial blood. The resulting flow-independent angiograms depict vessels with any orientation and flow velocity. No extrinsic contrast agent is required. Muscle is the dominant source of background signal in normal volunteers. However, long-T2 deep venous blood and nonvascular fluids such as edema also contribute background signal in some patients. Three sets of imaging parameters are described to address patient-specific contrast requirements. A rapid, spiral-based, three-dimensional readout is utilized to generate high-resolution angiograms of the lower extremities. Comparisons with x-ray angiography and two-dimensional time-of-flight angiography indicate that this flow-independent technique has unique capabilities to accurately depict stenoses and to visualize slow flow and in-plane vessels.
Brittain
J H
JH
Department of Electrical Engineering, Stanford University, California, USA.
Olcott
E W
EW
Szuba
A
A
Gold
G E
GE
Wright
G A
GA
Irarrazaval
P
P
Nishimura
D G
DG
D000792:Angiography / Q000379:methods; D001783:Blood Flow Velocity; D001808:Blood Vessels / Q000502:physiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007866:Leg / Q000098:blood supply; D018810:Magnetic Resonance Angiography / Q000379:methods*; D016491:Peripheral Vascular Diseases / Q000175:diagnosis; D012680:Sensitivity and Specificity