First-pass renal perfusion imaging using MS-325, an albumin-targeted MRI contrast agent

RATIONALE AND OBJECTIVES. MR angiography is proving to be a useful clinical study for the diagnosis of vascular disorders of renal arteries. However, its utility in terms of stenosis characterization is still limited, Renal p erfusion could provide supplemental information that could allow for a comp rehensive evaluation of renal artery stenosis by MR imaging. METHODS. MS-325 is a small-molecule blood pool agent that reversibly binds with serum albumin and hence leads to higher relaxivity and longer residenc e times in the blood. In this study, the authors evaluated the use of MS-32 5 to perform first-pass perfusion imaging and contrast-enhanced AIR angiogr aphy in the characterization of renal artery stenosis in an animal model. RESULTS. Quantitative perfusion estimates were obtained in the renal cortex (258 +/- 19.8 mL/min/100 g) and are comparable to microsphere measurements (198 +/- 12.2 mL/min/100 g), given the practical constraints, Based on the se measurements, perfusion showed minimal changes even when the diameter re ductions reached 75%. CONCLUSIONS. MS-325 could provide quantitative perfusion estimates that whe n combined with MR angiography may lead to comprehensive evaluation of rena l artery stenosis.