Comprehensive evaluation of the ischemic leg

Institution:	Stanford University
Investigator(s):	Dwight Nishimura, Ph.D.
Award Cycle:	2000 (Cycle 9)	Grant #: 9RT-0024	Award: $672,390
Subject Area:	General Biomedical Science
Award Type:	Research Project Awards

Abstracts

Initial Award Abstract

Smoking is the most important risk factor for diseases of arteries in the leg. Seventy to ninety percent of these patients are smokers. These diseases can substantially reduce the amount of blood flow into the calf and foot. As a result, this disease can lead to severe pain while walking (or even at rest), gangrene, and the need for amputation.

The number of cigarettes smoked is directly related to the severity of the disease. Among patients with more severe disease, surgery to restore blood flow to the lower leg is known to provide relief. However, this treatment remains effective for only about 50-70% of such patients after 5 years, with smokers suffering from an even poorer rate. Recently, a new form of treatment using angiogenic agents has attracted interest because these agents have been shown to cause growth of new blood vessels in the leg.

To take advantage of these established and new treatments, more accurate and lower risk ways of measuring the blood flow and the narrowing of the arteries in the leg are needed.

Therefore the main goal of this research project is to develop several methods involving magnetic resonance technology to perform a comprehensive evaluation of blood vessel disease in the leg. For such evaluation, these magnetic resonance methods will produce the following information: 1) pictures showing the state of the main blood vessels in the leg; 2) numbers indicating how much blood is flowing into the lower leg; and 3) pictures of the leg showing which regions are receiving and not receiving blood. Magnetic resonance, which uses only magnets to produce pictures of the body, poses no health risk to the patient.

These methods will be a significant improvement over existing noninvasive methods because such a comprehensive set of information cannot be produced by the other methods. The research plan includes development and optimization of the magnetic resonance methods followed by a study on patients with severe disease to test the effectiveness of the new methods.

Publications

Characterization and reduction of the transient response in steady-state MR imaging
Periodical: Magnetic Resonance in Medicine			Index Medicus:
Authors: Hargreaves BA, Vasanawala S, Pauly JM, Nishimura DG				ART
Yr: 2001	Vol: 46	Nbr:	Abs:	Pg: 149 - 158

Oscillating dual-equilibrium steady-state angiography
Periodical: Magnetic Resonance in Medicine			Index Medicus:
Authors: Overall WR, Nishimura DG, and Hu BS				ART
Yr: 2002	Vol: 47	Nbr:	Abs:	Pg: 513 - 522

Fat suppressed steady-state free precession imaging using phase detection
Periodical: Magnetic Resonance in Medicine			Index Medicus:
Authors: Hargreaves B, Vasanawala S, Nayak K, Hu B, Nishimura D				ART
Yr: 2003	Vol: 50	Nbr: 1	Abs:	Pg: 210-213

Rapid measurement of time-averaged blood flow using ungated spiral phase-contrast
Periodical: Magnetic Resonance in Medicine			Index Medicus:
Authors: Park J, Olcott E, Nishimura D				ART
Yr: 2003	Vol: 49	Nbr: 2	Abs:	Pg: 322-328

Fast phase-contrast velocity measurement in the steady state.
Periodical: Magnetic Resonance in Medicine			Index Medicus:
Authors: Overall WR, Nishimura DG, Hu BS				ART
Yr: 2002	Vol: 48	Nbr: 5	Abs:	Pg: 890-899

First-pass perfusion imaging of the lower limb.
Periodical: Journal of Cardiovasc. Magn. Reson.			Index Medicus:
Authors: Lee JH, Hu BS, Nishimura DG				ART
Yr: 2004	Vol: 6	Nbr:	Abs:	Pg: 381-383

Characterization and reduction of the transient response in steady-state MR imaging
Periodical: Magnetic Resonance in Medicine			Index Medicus:
Authors: Hargreaves BA, Vasanawala S, Pauly JM, Nishimura DG				ART
Yr: 2001	Vol: 46	Nbr:	Abs:	Pg: 149 - 158

Oscillating dual-equilibrium steady-state angiography
Periodical: Magnetic Resonance in Medicine			Index Medicus:
Authors: Overall WR, Nishimura DG, and Hu BS				ART
Yr: 2002	Vol: 47	Nbr:	Abs:	Pg: 513 - 522

Fat suppressed steady-state free precession imaging using phase detection
Periodical: Magnetic Resonance in Medicine			Index Medicus:
Authors: Hargreaves B, Vasanawala S, Nayak K, Hu B, Nishimura D				ART
Yr: 2003	Vol: 50	Nbr: 1	Abs:	Pg: 210-213

Rapid measurement of time-averaged blood flow using ungated spiral phase-contrast
Periodical: Magnetic Resonance in Medicine			Index Medicus:
Authors: Park J, Olcott E, Nishimura D				ART
Yr: 2003	Vol: 49	Nbr: 2	Abs:	Pg: 322-328

Fast phase-contrast velocity measurement in the steady state.
Periodical: Magnetic Resonance in Medicine			Index Medicus:
Authors: Overall WR, Nishimura DG, Hu BS				ART
Yr: 2002	Vol: 48	Nbr: 5	Abs:	Pg: 890-899

First-pass perfusion imaging of the lower limb.
Periodical: Journal of Cardiovasc. Magn. Reson.			Index Medicus:
Authors: Lee JH, Hu BS, Nishimura DG				ART
Yr: 2004	Vol: 6	Nbr:	Abs:	Pg: 381-383