Yong Wu1, Zhen Yao1, Gareth Kafka1,
David Farrell1, Mark Griswold2, Robert Brown1
1Department of Physics, Case Western
Reserve University, Cleveland, OH, United States; 2Department of
Radiology, Case Western Reserve University, Cleveland, OH, United States
Magnetic
particle imaging (MPI) is a new tomographic technique that allows fast,
inexpensive imaging of MRI contrast ferrofluid agents with submillimeter
resolution. Selection fields combined
with oscillating driving fields can move unsaturated field-free-points so as
to cover the field of view. In
previous studies, the average magnetization is assumed to respond
instantaneously to changes in the applied field. Realistically, however, a finite relaxation
time slows the magnetic response. The
present simulation demonstrates that, for contrast agents of interest, the
choice of an optimal particle size is strongly dependent on this effect. A trade-off thus exists between sensitivity
and resolution.
Keywords