Semi-Automated Correction of Phase Errors in Optimized Pseudo-Continuous Arterial Spin Labeling

David D. Shin¹, Youngkyoo Jung¹, Ajit Shankaranarayanan², Khaled Restom¹, Jia Guo¹, Wen-Ming Luh³, Peter Bandettini³, Eric C. Wong¹, Thomas T. Liu¹

The optimized pseudo-continuous arterial spin labeling (Opt-PCASL) is a variant of the PCASL method that provides higher tagging efficiency through estimation and correction of phase errors. The original implementation required extensive user-intervention, including subjective definition of vascular territories and manual input of scan parameters. A new automated optimization procedure incorporates vascular territory imaging for objective measure of vessel territory maps and a scan process that requires minimal user intervention. In three healthy subjects, the phase errors were reduced below 15 after one calibration step. The approach is expected to facilitate the use of the Opt-PCASL technique for quantitative fMRI studies.