title: Isolating quantum coherences in structural imaging using intermolecular double-quantum coherence MRI.
abstract: Intermolecular multiple-quantum coherence (iMQC) MR imaging provides a fundamentally different contrast mechanism. It allows probing tissue microstructure by tuning the direction and strength of the correlation gradient. However, iMQC images of a specific quantum-coherence can easily be contaminated by leakage signals from undesired quantum coherences (zero, single, and triple quantum coherence in this work). Using a modified double-quantum CRAZED imaging sequence, we show that signals originating from various coherence orders (M=0, 1, 2, 3) can be predicted in k-space and effectively isolated by means of a four-step phase cycling scheme and judicious choice of flip angles. Finally, preliminary data suggest the method to be able to provide information on trabecular bone architecture such as regional mean trabecular plate separation.
authors.affiliation: Department of Radiology, University of Pennsylvania Medical Center, Philadelphia, PA 19104-4283, USA.
authors.forename: Chih-Liang
authors.initials: CL
authors.lastname: Chin
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Tang
authors.forename: Louis-S
authors.initials: LS
authors.lastname: Bouchard
authors.forename: Punam K
authors.initials: PK
authors.lastname: Saha
authors.forename: Warren S
authors.initials: WS
authors.lastname: Warren
authors.forename: Felix W
authors.initials: FW
authors.lastname: Wehrli
mesh_terms: D000465:Algorithms; D003461:Crystallography / Q000379:methods*; D005240:Feasibility Studies; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D011789:Quantum Theory; D011884:Radius / Q000033:anatomy & histology*; D012815:Signal Processing, Computer-Assisted; D025321:Surgery, Computer-Assisted