Impact of Motion on T1 Mapping Acquired With Inversion Recovery Fast Spin Echo and Rapid Spoiled Gradient Recalled-Echo Pulse Sequences for Delayed Gadolinium-Enhanced MRI of Cartilage (dGEMRIC) in Volunteers

Purpose: To evaluate the impact of motion on T1 values acquired by using either inversion-recovery fast spin echo (IR-FSE) or three-dimensional (3D) spoiled gradient recalled echo (SPGR) sequences for delayed gadolinium enhanced magnetic resonance imaging of cartilage (dGEMRIC) in volunteers. Materials and Methods: Single-slice IR-FSE and 3D SPGR sequences were applied to perform dGEMRIC in five healthy volunteers. A mutual information-based approach was used to correct for image misregistration. Displacements were expressed as averaged Euclidean distances and angles. Averages of differences in goodness of fit (Delta chi(2)) tests and averages of relative differences in T1 values (Delta T1) before and after motion correction were computed. Results: Maximum Euclidean distance was 3.5 mm and 1.2 mm for IR-FSE and SPGR respectively. Mean +/- SD of Delta chi(2) were 10.18 +/- 8.4 for IR-FSE and -1.37 +/- 5.5 for SPGR. Mean +/- SD of Delta T1 were 0.008 +/- 0.0048 for IR-FSE and -0.002 +/- 0.019 for FSPGR. Pairwise comparison of Delta chi(2) values showed a significant difference for IR-FSE, but not for 3D-SPGR. Significantly greater variability in T1 values was also noted for IR-FSE than for 3D-SPGR. Conclusion: Involuntary motion has a significant influence on Ti values acquired with IR-FSE, but not with 3D-SPGR in healthy volunteers.