Feasibility and reproducibility of whole brain myelin water mapping in 4 minutes using fast acquisition with spiral trajectory and adiabatic T2prep (FAST‐T2) at 3T. Issue 2 (29th August 2015)

• Record Type: Journal Article
• Authors: Nguyen, Thanh D.; Deh, Kofi; Monohan, Elizabeth; Pandya, Sneha; Spincemaille, Pascal; Raj, Ashish; Wang, Yi; Gauthier, Susan A.
• Is Part Of: Magnetic resonance in medicine. Volume 76:Issue 2(2016)
• Page Start: 456
• Page End: 465
• Publication Date: 2015-08-29
• Subjects: T2 relaxometry -- BIR‐4 -- myelin water fraction -- spiral sampling -- 3T; Nuclear magnetic resonance -- Periodicals; Electron paramagnetic resonance -- Periodicals; 616.07548
• DOI: 10.1002/mrm.25877
• Languages: English
• ISSNs: 0740-3194

Abstract

Abstract : Purpose: To develop and measure the reproducibility of 4‐min whole brain myelin water fraction (MWF) mapping using fast acquisition with spiral trajectory and T2prep (FAST‐T2) sequence at 3T. Methods: Experiments were performed on phantoms, 13 volunteers, and 16 patients with multiple sclerosis. MWF maps were extracted using a spatially constrained non‐linear algorithm. The proposed adiabatic modified BIR‐4 (mBIR‐4) T2prep was compared with the conventional composite T2prep (COMP). The effect of reducing the number of echo times (TEs) from 15 to 6 (reducing scan time from 10 to 4 min) was evaluated. Reproducibility was assessed using correlation analysis, coefficient of variation (COV), and Bland–Altman plots. Results: Compared with COMP, mBIR‐4 provided more accurate T2 in phantoms and better MWF maps in human brains. Reducing the number of TEs had a negligible effect on MWF map quality, with a regional MWF difference of <0.8%. Regional MWFs obtained by repeated scans showed excellent correlation (R = 0.99), low COV (1.3%–2.4%), and negligible bias within ±1% limits of agreement. On a voxel‐wise basis, the agreement remained strong (correlation R = 0.89 ± 0.03, bias = 0.01% ± 0.29%, limits of agreement = [−3.35% ± 0.73%, 3.33% ± 0.61%]). Conclusion: Whole brain MWF mapping with adiabatic FAST‐T2 is feasible in 4 min and provides good intrasite reproducibility. Magn Reson Med 76:456–465, 2016. © 2015 Wiley Periodicals, Inc.