title: Flip angle profile correction for T₁ and T₂ quantification with look-locker inversion recovery 2D steady-state free precession imaging.
abstract: Fast methods using balanced steady-state free precession have been developed to reduce the scan time of T₁ and T₂ mapping. However, flip angle (FA) profiles created by the short radiofrequency pulses used in steady-state free precession deviate substantially from the ideal rectangular profile, causing T₁ and T₂ mapping errors. The purpose of this study was to develop a FA profile correction for T₁ and T₂ mapping with Look-Locker 2D inversion recovery steady-state free precession and to validate this method using 2D spin echo as a reference standard. Phantom studies showed consistent improvement in T₁ and T₂ accuracy using profile correction at multiple FAs. Over six human calves, profile correction provided muscle T₁ estimates with mean error ranging from excellent (-0.6%) at repetition time/FA = 18 ms/60° to acceptable (6.8%) at repetition time/FA = 4.9 ms/30°, while muscle T₂ estimates were less accurate with mean errors of 31.2% and 47.9%, respectively.
authors.affiliation: Department of Biomedical Engineering, Cornell University, Ithaca, New York, USA.
authors.forename: Mitchell A
authors.initials: MA
authors.lastname: Cooper
authors.forename: Thanh D
authors.initials: TD
authors.lastname: Nguyen
authors.forename: Pascal
authors.initials: P
authors.lastname: Spincemaille
authors.forename: Martin R
authors.initials: MR
authors.lastname: Prince
authors.forename: Jonathan W
authors.initials: JW
authors.lastname: Weinsaft
authors.forename: Yi
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000465:Algorithms; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D018482:Muscle, Skeletal / Q000033:anatomy & histology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity