Relaxivity Tissue Differentiation Among Gd-Based Contrast Agents in Ex-Vivo Mouse Embryo Imaging

Michael David Wong¹, X Josette Chen¹, R Mark Henkelman¹

The role of MRI in developmental biology, specifically in mouse embryo organogenesis and phenotyping, is significantly increasing due to technologies that allow for high image resolution and throughput. The majority of ex-vivo MRI mouse embryo studies improve image contrast and SNR by immersing the sample into some concentration of Gd-based contrast agent. It is widely believed that all gadolinium-based contrast agents have identical tissue interactions and provide similar MRI images despite the differences in Gd-chelates. Here, relaxivity (r1) variation amongst mouse embryo organs is observed for one class of contrast agents, while homogeneity is seen throughout the embryo for another.