Optimization for parameters of 5.0T pseudo continuous arterial spin labeling MRI of whole brain
Objective To explore the optimization for parameters of 5.0T pseudo continuous arterial spin labeling(pCASL)MRI of whole brain.Methods Nine healthy adults were prospectively enrolled,and single-delay pCASL scanning was performed based on a 5.0T MR scanner with 3 sets of labeling gradients:Group A,average gradient(Gavg)=1 mT/m and the ratio of maximum gradient(Gmax)to Gavg(Gratio)=10,group B,Gavg=0.6 mT/m and Gratio=10,group C,Gavg=0.3 mT/m and Gratio=9.The labeling efficiency and cerebral blood flow(CBF)of 3 groups were compared to screen the best labeling gradient group.Results When the marked average blood flow velocity was 40 cm/s,the gradient field tolerance of group C was better than that of group A and B at the situation of reduced B1+and larger B0 offset frequency range.Under the gradient field of group C,the level of labeled artery B1 ranged from 54.19％to 75.36％,with an average of 64.71％.The labeling efficiencies of group C were all ≥85％,and all ≥90％at the average B1 level(64.71％).In the whole gray matter and almost all brain regions,CBF on pCASL under gradient field of group C was significantly higher than that of group A and B(all P＜0.05).Conclusion Low Gavg and low Gmax were the optimal parameters for 5.0T whole brain pCASL MRI.
万方数据
维普
