Gadofosveset-based biomarker of tissue albumin concentration: Technical validation in vitro and feasibility in vivo

• Published in: Magnetic resonance in medicine Vol. 73; no. 1; pp. 244 - 253
• Main Authors: Richardson, Owen C., Bane, Octavia, Scott, Marietta L.J., Tanner, Steven F., Waterton, John C., Sourbron, Steven P., Carroll, Timothy J., Buckley, David L.
• Format: Journal Article
• Language: English
• Published: United States Blackwell Publishing Ltd 01.01.2015; Wiley Subscription Services, Inc; BlackWell Publishing Ltd
• Subjects: Adult; albumin; Albumins - metabolism; binding; biomarker; Biomarkers - metabolism; Computer Simulation; Contrast Media - pharmacokinetics; Feasibility Studies; Female; gadofosveset; Gadolinium - pharmacokinetics; Heart - anatomy & histology; Humans; Image Interpretation, Computer-Assisted - methods; Imaging Methodology—Full Papers; Magnetic Resonance Imaging - methods; Male; Models, Biological; Molecular Imaging - methods; Myocardium - metabolism; Organometallic Compounds - pharmacokinetics; relaxivity; Reproducibility of Results; Sensitivity and Specificity; Tissue Distribution; binding; relaxivity; gadofosveset; biomarker; albumin
• ISSN: 0740-3194; 1522-2594
• DOI: 10.1002/mrm.25128

Purpose There is currently no adequate method of mapping physiologic and pathophysiologic tissue albumin concentrations in human subjects. The objective of this study was to devise and evaluate a biomarker of regional albumin concentration using gadofosveset‐enhanced MRI. Theory and Methods A binding and relaxation model was devised and evaluated in vitro in solutions of albumin at 3.0 Tesla (T) and 4.7T. The method was evaluated in the heart in seven volunteers at 3.0T. Results MRI‐derived estimates of albumin concentration were in good agreement with true values over the range 0.1–1.0 mM (Pearson correlation coefficients of 0.85 and 0.88 for 3.0T and 4.7T, respectively). The mean calculated albumin concentration in the myocardium for the volunteers was 0.02 mM (range, 0.01–0.03 mM). Conclusion Accurate estimates of albumin concentration in vitro suggest this may be a viable noninvasive alternative to existing techniques. In the myocardium the MRI‐derived estimates of albumin concentration indicate the practical feasibility of the technique but were below expected values. Gadofosveset‐enhanced MR relaxometry has potential in providing biomarkers of regional albumin concentration; further evaluation is required before it can be used reliably in vivo. Magn Reson Med 73:244–253, 2015. © 2014 Wiley Periodicals, Inc.