Enhancement of respiratory navigator-gated three-dimensional spoiled gradient-recalled echo sequence with variable flip angle scheme.

摘要: Purpose To develop and demonstrate the feasibility of a new technique for respiratory-gated, fat-suppressed, three-dimensional spoiled gradient-recalled echo (3D-SPGR) with navigator gating more accurate robust motion detection. Methods A navigator-gated 3D-SPGR was modified to include wait period immediately prior sequence magnetization recovery. Furthermore, variable flip angle scheme realized by combination ramp-up, ramp-down, attenuation strategies optimizing point spread functions. Phantom human experiments were conducted our on 1.5T scanners. Results Using method, T1-weighted 3D images improved signal homogeneity acquired maximum 30° in phantom tests. Also, compared conventional 3D-SPGR, respiratory detection free-breathing subjects provided, leading reduced artifacts. Conclusion The insertion method both accuracy image study. Magn Reson Med 72:172–177, 2014. © 2013 Wiley Periodicals, Inc.