Improving Spatial Normalization of Brain Diffusion MRI to Measure Longitudinal Changes of Tissue Microstructure in the Cortex and White Matter

JACOBACCI, FLORENCIA; AMARO, EDSON; DELLA MAGGIORE, VALERIA; LERNER, GONZALO; DOYON, JULIEN; LERNER, GONZALO; DOYON, JULIEN; JOVICICH, JORGE; ARMONY, JORGE L.; JOVICICH, JORGE; ARMONY, JORGE L.; JACOBACCI, FLORENCIA; AMARO, EDSON; DELLA MAGGIORE, VALERIA

JMRI - JOURNAL MAGNETIC RESONANCE IMAGING

JOHN WILEY & SONS INC

Año: 2020

1053-1807

Background: Fractional anisotropy (FA) and mean diffusivity (MD) are frequently used to evaluate longitudinal changes in white matter (WM) microstructure. Recently, there has been a growing interest in identifying experience-dependent plasticity in gray matter using MD. Improving registration has thus become a major goal to enhance the detection of subtle longitudinal changes in cortical microstructure.Purpose: To optimize normalization of diffusion tensor images (DTI) to improve registration in gray matter and reduce variability associated with multisession registrations.Study type: Prospective longitudinal study.Subjects: Twenty-one healthy subjects (18-31 years old) underwent nine MRI scanning sessions each.Field strength/sequence: 3.0T, diffusion-weighted multiband-accelerated sequence, MP2RAGE sequence.Assessment: Diffusion-weighted images were registered to standard space using different pipelines that varied in the features used for normalization, namely, the nonlinear registration algorithm (FSL vs. ANTs), the registration target (FA-based vs. T1 -based templates), and the use of intermediate individual (FA-based or T1 -based) targets. We compared the across-session test-retest reproducibility error of these normalization approaches for FA and MD in white and gray matter.Statistical tests: Reproducibility errors were compared using a repeated-measures analysis of variance with pipeline as the within-subject factor.Results: The registration of FA data to the FMRIB58 FA atlas using ANTs yielded lower reproducibility errors in white matter (P < 0.0001) with respect to FSL. Moreover, using the MNI152 T1 template as the target of registration resulted in lower reproducibility errors for MD (P < 0.0001), whereas the FMRIB58 FA template performed better for FA (P < 0.0001). Finally, the use of an intermediate individual template improved reproducibility when registration of the FA images to the MNI152 T1 was carried out within modality (FA-FA) (P < 0.05), but not via a T1 -based individual template.Data conclusion: A normalization approach using ANTs to register FA images to the MNI152 T1 template via an individual FA template minimized test-retest reproducibility errors both for gray and white matter.