Rapid and robust variable flip angle T1mapping using interleaved two-dimensional multislice spoiled gradient echo imaging.
Conventional T1mapping using three-dimensional (3D) radiofrequency (RF) spoiled gradient echo (SPGR) imaging with short repetition times (TR) is adversely affected by incomplete spoiling (i.e. residual T2dependency). In this work, an optimized interleaved 2D multislice SPGR sequence scheme and an adapted postprocessing procedure are evaluated for highly T2-insensitive T1quantification of human brain tissues.



An efficient 2D multislice SPGR protocol including a relatively long TR of 200 ms is investigated with careful consideration of cross talk and magnetization transfer effects. Based on the derived scan protocol, T1is quantified from the signal ratio of two SPGR datasets acquired at different flip angles. The effect of nonideal RF excitation profiles is incorporated into the SPGR signal model by performing Bloch simulations.



Simulations showed that the parameters of the SPGR protocol (such as TR and the spoiler gradient moments) guarantee virtually complete spoiling. This result was confirmed by T1measurements both in vitro using a 2% agar probe doped with 0.1 mM Gd (Gadovist) and in vivo in the human brain.



The derived 2D multislice SPGR protocol offers efficient, highly reproducible, and in particular T2-insensitive T1quantification of human brain tissues. Magn Reson Med 77:1606-1611, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
Division of Radiological Physics, Department of Radiology, University of Basel Hospital, Basel, Switzerland.|Department of Biomedical Engineering, University of Basel, Basel, Switzerland.
Rahel
R
Heule
Division of Radiological Physics, Department of Radiology, University of Basel Hospital, Basel, Switzerland.|Department of Biomedical Engineering, University of Basel, Basel, Switzerland.
Oliver
O
Bieri
D000465:Algorithms; D001921:Brain / Q000033:anatomy & histology*; D003198:Computer Simulation; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D015233:Models, Statistical; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted
T1 mapping; fast imaging; human brain tissues; interleaved 2D multislice sequence; spoiled gradient echo (SPGR)