Abstract #1469

Point-Spread-Functions for RF Imaging with TRASE: Implications for Phase Gradient Coil Design and Flip Angle Calibration

Jonathan C. Sharp¹, Donghui Yin², Boguslaw Tomanek¹, Scott B. King²

¹Institute for Biodiagnostics (West), National Research Council of Canada, Calgary, AB, Canada; ²Institute for Biodiagnostics, National Research Council of Canada, Winnipeg, MB, Canada

Imaging without B0-gradients by the TRASE method is based on echo trains with refocusing pulses produced by RF phase gradient fields. K-space evolution occurs between successive echoes. The use of phase gradients means that pulse phases vary spatially. Also |B1| inhomogeneity, causing flip-angle errors, is always present. Both effects combine to result in each location in the sample experiencing a different pulse sequence, which results in a position-dependent point-spread-function (PSF). We examine how the relationships between sequence design, coil design and flip angle calibration can be used to maximize the sample volume offering a good PSF.