Abstract:
PURPOSE:To optimize and investigate the influence of bipolar gradients for flow suppression in metabolic quantification of hyperpolarized 13 C chemical shift imaging (CSI) of mouse liver at 9.4 T. METHODS:The trade-off between the amount of flow suppression using bipolar gradients and T2* effect from static spins was simulated. A free induction decay CSI sequence with alternations between the flow-suppressed and non-flow-suppressed acquisitions for each repetition time was developed and was applied to liver tumor-bearing mice via injection of hyperpolarized [1-13 C] pyruvate. RESULTS:The in vivo results from flow suppression using the velocity-optimized bipolar gradient were comparable with the simulation results. The vascular signal was adequately suppressed and signal loss in stationary tissue was minimized. Application of the velocity-optimized bipolar gradient to tumor-bearing mice showed reduction in the vessel-derived pyruvate signal contamination, and the average lactate/pyruvate ratio increased by 0.095 (P < 0.05) in the tumor region after flow suppression. CONCLUSION:Optimization of the bipolar gradient is essential because of the short 13 C T2* and high signal in venous flow in the mouse liver. The proposed velocity-optimized bipolar gradient can suppress the vascular signal, minimizing T2*-related signal loss in stationary tissues at 9.4 T. Magn Reson Med 78:1674-1682, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Lee H,Lee J,Joe E,Yang S,Song JE,Choi YS,Wang E,Joo CG,Song HT,Kim DHdoi
10.1002/mrm.26578subject
Has Abstractpub_date
2017-11-01 00:00:00pages
1674-1682issue
5eissn
0740-3194issn
1522-2594journal_volume
78pub_type
杂志文章abstract:PURPOSE:Myocardial effective relaxation time T2* is commonly regarded as a surrogate for myocardial tissue oxygenation. However, it is legitimate to assume that there are multiple factors that influence T2*. To this end, this study investigates the relationship between T2* and cardiac macromorphology given by left vent...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
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journal_title:Magnetic resonance in medicine
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