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bioRxiv · 10.1101/590521

Improving spatial normalization of brain diffusion MRI to measure longitudinal changes of tissue microstructure in human cortex and white matter.

Jacobacci, F.·Jovicich, J.·Lerner, G.·Amaro, E.·Armony, J.·Doyon, J.·Della-Maggiore, V.
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Abstract

BackgroundFractional anisotropy (FA) and mean diffusivity (MD) are frequently used to evaluate longitudinal changes in white matter 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. PurposeTo optimize normalization to improve registration in gray matter and reduce variability associated with multi-session registrations. Study TypeProspective longitudinal study SubjectsTwenty-one healthy subjects (18-31 years old) underwent 9 magnetic resonance imaging (MRI) scanning sessions each. Field Strength/Sequence3.0T, diffusion-weighted multiband-accelerated sequence, MP2RAGE sequence. AssessmentDiffusion-weighted images were registered to standard space using different pipelines that varied in the features used for normalization, namely the non-linear 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 from these normalization approaches for FA and MD in white and gray matters. Statistical TestsReproducibility errors were compared using a repeated-measures analysis of variance with pipeline as within-subject factor. ResultsThe 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 ConclusionA 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.

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Jacobacci, F., Jovicich, J., Lerner, G., Amaro, E., Armony, J., Doyon, J., Della-Maggiore, V.. 2019-03-28. Improving spatial normalization of brain diffusion MRI to measure longitudinal changes of tissue microstructure in human cortex and white matter.. https://doi.org/10.1101/590521

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