Comparison of MR lymphangiography with a G6 macromolecular contrast agent obtained at 1.5T and 3.0T Systems
Kobayashi H, Bernardo M, Regino C, Koyama Y, Hama Y, Brechbiel M, Choyke P
Since most of macro-molecular contrast agents show decreased R1 and increased R2 relaxivities in a high magnetic field, T1 contrast induced by macromolecular contrast agents can be compromised on 3T compared with 1.5T. We consecutively performed MR lymphangiograpy in mice with a G6 dendrimer-based nano-sized contrast agent both on 3T and 1.5T to evaluate the effect of high magnetic field on a macromolecular contrast agent. The lymph node-to-fat contrast was compromised with both 3D-fastSPGR and 3D-FIESTA-C on the 3T system compared with the 1.5T system probably because of decreased R1 relaxivity of G6 agent and possible T2 and T2* effects.