David Dongsuk Shin1, Ho-Ling Liu2, Ajit Shankaranarayanan3, Thomas T. Liu1
1Center for Functional MRI, University of California, San Diego, La Jolla, CA, United States; 2Department of Medical Imaging & Radiological Sciences, Chang Gung University, Taiwan; 3GE Healthcare, Waukesha, WI, United States
In PCASL, accurate and reliable CBF estimates can be complicated by variations in tagging efficiency (α) caused by phase tracking errors. We present a new technique named α-corrected PCASL, which compensates for tagging efficiency variations on a per voxel basis. The key component of this technique is the accurate estimation of the phase errors and the associated tagging efficiency map. In a healthy subject, CBF estimates obtained with OptPCASL and α-corrected PCASL were similar (87.7 vs. 86.0 ml/100ml-min), while conventional PCASL estimates were lower (78.4 ml/100ml-min). For phase tracking errors < 30 degrees, CBF quantification error is less than 2.85%.