title: Isolating chemical exchange saturation transfer contrast from magnetization transfer asymmetry under two-frequency rf irradiation.
abstract: Chemical exchange saturation transfer (CEST), arising from mobile groups, and magnetization transfer (MT) contrast arising from immobile protons, have enjoyed wide popularity recently in MRI applications. It is often difficult to separate genuine CEST signatures from MT effects, which are asymmetric with respect to the water resonance. A two-pool model for magnetization transfer (MT) is established based on Provotorov's theory of saturation, and then extended to the situation of simultaneous two-frequency rf irradiation. Numerical simulations and experimental results demonstrate that two-frequency rf irradiation can flatten out MT asymmetry when both frequency components lie within the spectrum of an MT pool. Based on this result, we propose a strategy to isolate chemical exchange saturation transfer (CEST) contrast from MT asymmetry contrast by using the two-frequency rf irradiation technique.
authors.affiliation: Quantitative Multinuclear Musculoskeletal Imaging Group, Center for Biomedical Imaging, Department of Radiology, New York University, Langone Medical Center, New York, NY 10016, USA.
authors.forename: Jae-Seung
authors.initials: JS
authors.lastname: Lee
authors.forename: Ravinder R
authors.initials: RR
authors.lastname: Regatte
authors.forename: Alexej
authors.initials: A
authors.lastname: Jerschow
mesh_terms: D000465:Algorithms; D000818:Animals; D002358:Cartilage, Articular / Q000033:anatomy & histology / Q000737:chemistry; D002417:Cattle; D002809:Chondroitin Sulfates / Q000737:chemistry; D004574:Electromagnetic Fields; D005780:Gelatin / Q000737:chemistry; D008279:Magnetic Resonance Imaging / Q000379:methods*; D015233:Models, Statistical; D019047:Phantoms, Imaging; D011522:Protons; D011846:Radio Waves; D013816:Thermodynamics
chemical_list: D011522:Protons; D005780:Gelatin; D002809:Chondroitin Sulfates