Erik Holt Clayton1, Joel R. Garbow2,
Philip V. Bayly1,3
1Mechanical Aerospace & Structural
Engineering, Washington University in St. Louis, Saint Louis, MO, United
States; 2Biomedical MR Laboratory, Mallinckrodt Institute of
Radiology, Washington University School of Medicine, Saint Louis, MO, United
States; 3Biomedical Engineering, Washington University in St.
Louis, Saint Louis, MO, United States
Multifrequency
MR elastography (MRE) has been used to measure mechanical stiffness of human
brain tissue. The development of cancer treatment protocols may benefit from
similar studies in rodent models. Here the viscoelastic material properties
of mouse brain were determined by MRE over a range of driving frequencies
(600 - 1800 Hz). A novel non-invasive brain actuator was devised to introduce
propagating shear waves. Wave motion was imaged with a phase-locked spin echo
pulse sequence. Displacement data were inverted in a least-squares manner to
obtain complex modulus estimates. Results suggest the frequency response of
brain tissue may provide diagnostic value.