1. From the Saint Vincent Hospital, Department of Internal Medicine, Worcester, MA (Z.H.)
2. University of Pennsylvania Perelman School of Medicine, Center for Magnetic Resonance and Optical Imaging, Philadelphia (J.L., S.G., G.O., I.V., J.A.C.)
3. Hospital of the University of Pennsylvania, Philadelphia (J.L., S.G., B.A., G.O., A.M., J.A.C.)
4. Corporal Michael J. Crescenz VAMC, Philadelphia, PA (S.G., G.O., K.J., I.V., S.A.).