title: Advantage of sampling density weighted apodization over postacquisition filtering apodization for sodium MRI of the human brain.
abstract: For sodium imaging of the human brain, Gibbs' ringing can degrade image appearance and confound image analysis; k-space filtering is generally required. In this work, the signal to noise ratio (SNR) advantage of sampling density weighted apodization (SDWA) over uniform k-space sampling with postacquisition filtering apodization (UPFA) is quantified for sodium three-dimensional (3D) twisted projection imaging (TPI) of the human brain. A direct comparison was conducted with the creation of two TPI projection data sets (each with an equal number of projections of equal length): one generating uniform sampling density, and the other a "generalized Hamming" sampling density that conformed to 3D-TPI constraints for full k-space sampling. In this work it is shown theoretically, and then experimentally with sodium imaging of the human brain, that an SNR advantage of 17% is associated with the use of SDWA over UPFA for the filter presented, along with a significant noise-coloring benefit.
authors.affiliation: Department of Biomedical Engineering, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Robert
authors.initials: R
authors.lastname: Stobbe
authors.forename: Christian
authors.initials: C
authors.lastname: Beaulieu
mesh_terms: D000465:Algorithms; D001921:Brain / Q000033:anatomy & histology* / Q000378:metabolism*; D003198:Computer Simulation; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods*; D008954:Models, Biological; D015233:Models, Statistical; D019047:Phantoms, Imaging; D011522:Protons; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D012964:Sodium / Q000032:analysis*
chemical_list: D011522:Protons; D012964:Sodium