title: Turboprop+: enhanced Turboprop diffusion-weighted imaging with a new phase correction.
abstract: Faster periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) diffusion-weighted imaging acquisitions, such as Turboprop and X-prop, remain subject to phase errors inherent to a gradient echo readout, which ultimately limits the applied turbo factor (number of gradient echoes between each pair of radiofrequency refocusing pulses) and, thus, scan time reductions. This study introduces a new phase correction to Turboprop, called Turboprop+. This technique employs calibration blades, which generate 2-D phase error maps and are rotated in accordance with the data blades, to correct phase errors arising from off-resonance and system imperfections. The results demonstrate that with a small increase in scan time for collecting calibration blades, Turboprop+ had a superior immunity to the off-resonance-related artifacts when compared to standard Turboprop and recently proposed X-prop with the high turbo factor (turbo factor = 7). Thus, low specific absorption rate and short scan time can be achieved in Turboprop+ using a high turbo factor, whereas off-resonance related artifacts are minimized.
authors.affiliation: School of Electrical, Computer, and Energy Engineering, Ira A, Fulton School of Engineering, Arizona State University, Tempe, Arizona, USA.
authors.forename: Chu-Yu
authors.initials: CY
authors.lastname: Lee
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Li
authors.forename: James G
authors.initials: JG
authors.lastname: Pipe
authors.forename: Josef P
authors.initials: JP
authors.lastname: Debbins
mesh_terms: D000465:Algorithms; D016477:Artifacts; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted