Jamu K. Alford1, A. Gregory Sorensen1, Thomas Benner1, Blaine A. Chronik2, William Bradfield Handler2, Timothy J. Scholl3, Gunjan Madan4, Peter Caravan1
1Radiology, A. A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; 2Physics & Astronomy, The University of Western Ontario, London, ON, Canada; 3Department of Medical Biophysics, The University of Western Ontario, London, ON, Canada; 4Siemens Medical Solutions Inc., Malvern, PA, USA
The first direct protein imaging in a human volunteer is presented here. Delta relaxation enhanced MR, (dreMR) exploits the strong magnetic field dependence of slowly tumbling (e.g. bound) paramagnetic contrast agent. A volunteer with a broken finger was imaged after injection of the albumin-targeted contrast agent MS-325. A 1.5T, clinical MRI system outfitted with an electromagnetic insert (dreMR insert) was used acquire T1-weighted images at relaxation fields of 1.35 and 1.65T. The difference between the images shows contrast exclusive to the protein-bound contrast agent and demonstrated increased contrast in the inflamed tissue about the finger fracture.