Elena Kaye1,2, Kim Butts Pauly1
1Radiology, Stanford University, Palo
Alto, CA, United States; 2Electrical Engineering, Stanford University,
Palo Alto, CA, United States
MRgFUS
is of interest in the treatment of various brain pathologies, such as tumors
and neuropathic pain. One way to visualize the focal spot prior to the
treatment relies on MR acoustic radiation force imaging. A recent
implementation of MR-ARFI used a diffusion-weighted 2DFT sequence with a low
b-value. The goal of this work was to find the optimum b-value for the
displacement sensitizing gradient in MR-ARFI, relevant to in vivo human
imaging. The optimal b-value of 33 s/mm2 was found to minimize the ghosting
artifacts in vivo human brain images, and maximize displacement in the focal
spot of ex vivo porcine brain, while keeping ultrasound energy minimal.