Isolating quantum coherences in structural imaging using intermolecular double-quantum coherence MRI.
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.
Chin
Chih-Liang
CL
Department of Radiology, University of Pennsylvania Medical Center, Philadelphia, PA 19104-4283, USA.
Tang
Xiaoping
X
Bouchard
Louis-S
LS
Saha
Punam K
PK
Warren
Warren S
WS
Wehrli
Felix W
FW
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