Reducing false positives in tractography with microstructural and anatomical priors

Schiavi, S.; Barakovic, M.; Ocampo Pineda, M.; Descoteaux, M.; Thiran, J.-P.; Daducci, A.

doi:10.1101/608349

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bioRxiv · 10.1101/608349

Reducing false positives in tractography with microstructural and anatomical priors

Schiavi, S.·Barakovic, M.·Ocampo Pineda, M.·Descoteaux, M.·Thiran, J.-P.·Daducci, A.

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Abstract

Tractography is a family of algorithms that use diffusion-weighted magnetic resonance imaging data to reconstruct the white matter pathways of the brain. Although it has been proven to be particularly effective for studying non-invasively the neuronal architecture of the brain, recent studies have highlighted that the large incidence of false positive connections retrieved by these techniques can significantly bias any connectivity analysis. Some solutions have been proposed to overcome this issue and the ones relying on convex optimization framework showed a significant improvement. Here we propose an evolution of the Convex Optimization Modeling for Microstructure Informed Tractography (COMMIT) framework, that combines basic prior knowledge about brain anatomy with group-sparsity regularization into the optimization problem. We show that the new formulation dramatically reduces the incidence of false positives in synthetic DW-MRI data.

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Schiavi, S., Barakovic, M., Ocampo Pineda, M., Descoteaux, M., Thiran, J.-P., Daducci, A.. 2019-04-14. Reducing false positives in tractography with microstructural and anatomical priors. https://doi.org/10.1101/608349

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