Abstract #1692

Gd-Albumin Relaxivity in the Rat Thalamus In Vivo at 11.1 T

Garrett William Astary¹, Svetlana Kantorovich², Paul Richard Carney^1,3, Malisa Sarntinoranont⁴, Thomas Harold Mareci⁵

¹Biomedical Engineering, University of Florida, Gainesville, FL, United States; ²Neuroscience, University of Florida; ³Division of Pediatric Neurology, University of Florida; ⁴Mechanical & Aerospace Engineering, University of Florida; ⁵Biochemistry & Molecular Biology, University of Florida

A priori knowledge of contrast agent (CA) relaxivity (R₁ and R₂), which parameterizes how a CA alters neighboring water proton relaxation times (T₁ and T₂), can be used to determine the CA concentration in tissue, using pre- and post-contrast T₁-weighted scans and knowledge of inherent tissue T₁ values. The relaxivity of the CA gadolinium-labeled albumin (Gd-albumin) was measured in rat thalamus in vivo at 11.1 T and compared to the relaxivity of this CA measured in solution. R₁ and R₂ values in tissue were found to be reduced by 78% and 32%, respectively relative to solution values.