Fat-Constrained QSM for Abdominal Applications

Debra E. Horng¹, ², Diego Hernando¹, Samir D. Sharma¹, Scott B. Reeder¹, ²

Quantitative Susceptibility Mapping (QSM), which has been employed in brain applications to measure iron, also has the potential to quantify liver iron overload. However, unlike in the brain, the presence of abdominal fat provides a unique opportunity to constrain the ill-posed QSM estimation problem. In this work, we constrain the QSM estimation by assuming that the magnetic susceptibility of fat (and air) is constant in the presence of iron overload. Comparison of a conventional QSM constraint (ℓ1-regularization) to the proposed fat/air-constraint shows that the latter is more accurate even in the presence of background field variation and noise.