Ildar Khalidov1, Tian Liu1,
Xiaoyue Chen2, Moonso Jin2, Ali S. Arbab3,
Quan Jiang3, Martin Prince1, Yi Wang1
1Radiology, Weill Cornell Medical
College, NYC, NY, United States; 2Biomedical Engineering, Cornell
University, Ithaca, NY, United States; 3Neurology, Henry Ford
Hospital, Detroit, MI, United States
Quantitative
susceptibility mapping (QSM) is a technique that uses phase data from an MRI
image to estimate the susceptibility distribution in the object. It has been
demonstrated that QSM is able to correctly estimate the magnetic moment of
specimen differing in susceptibility to the surrounding tissue [1]. We would
like to exploit this ability to perform quantitative imaging of biomarkers in
animal imaging. However, animal imaging presents additional challenges: the
need for higher resolution suggests lower SNR; mixes of several tissues can
create significant artifacts that impede quantification. In this work, we
estimated the susceptibility change induced by SPIO nanoparticles that are
targeted to specific cells. In experiment (1), we scan a rat brain after
stroke injected with neural progenitor cells (NPCs) incubated in a solution
containing a suspension of ferumoxide-protamine sulfate. In experiment (2),
we image a mouse injected with SPIO nanoparticles that target the
intercellular adhesion molecule ICAM-1, which is induced in response to
inflammation. We use total-variation based regularization to circumvent the
problems with low SNR and the streaking artifacts.
Keywords