title: Correction for B(1) and B(0) variations in quantitative T(2) measurements using MRI.
abstract: A new method is described for compensating for the bias introduced by variations in radiofrequency (RF) field strength and main magnetic field strength when making quantitative T(2) measurements using MRI. Field measurements made during the MRI study are used in combination with a signal model for off-resonance and imperfect RF pulses to correct the estimated T(2) value at every voxel. Applicable to both multicomponent and conventional single-component T(2) studies, the method has been validated experimentally using paramagnetic salt solutions in a multicompartment phantom. Studies of the human head are used to demonstrate the method in practice.
authors.affiliation: McConnell Brain Imaging Centre, Montréal Neurological Institute, McGill University, Montréal, Québec, Canada. jgsled@bic.mni.mcgill.ca
authors.forename: J G
authors.initials: JG
authors.lastname: Sled
authors.forename: G B
authors.initials: GB
authors.lastname: Pike
mesh_terms: D016477:Artifacts; D001921:Brain / Q000473:pathology; D001931:Brain Mapping; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D016018:Least-Squares Analysis; D008279:Magnetic Resonance Imaging / Q000379:methods*; D017711:Nonlinear Dynamics; D012680:Sensitivity and Specificity