Along-Tract Statistical Mapping of Microstructural Abnormalities in Bipolar Disorder: A Pilot Study

Nabulsi, L.; Chandio, B. Q.; Dhinagar, N.; Laltoo, E.; McPhilemy, G.; Martyn, F. M.; Hallahan, B.; McDonald, C.; Thompson, P. M.; Cannon, D. M.

doi:10.1101/2023.03.07.531585

bioRxiv · 10.1101/2023.03.07.531585

Along-Tract Statistical Mapping of Microstructural Abnormalities in Bipolar Disorder: A Pilot Study

Nabulsi, L.·Chandio, B. Q.·Dhinagar, N.·Laltoo, E.·McPhilemy, G.·Martyn, F. M.·Hallahan, B.·McDonald, C.·Thompson, P. M.·Cannon, D. M.

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Abstract

Investigating brain circuitry involved in bipolar disorder (BD) is key to discovering brain biomarkers for genetic and interventional studies of the disorder. Even so, prior research has not provided a fine-scale spatial mapping of brain microstructural differences in BD. In this pilot diffusion MRI dataset, we used BUndle ANalytics (BUAN), a recently developed analytic approach for tractography, to extract, map, and visualize the profile of microstructural abnormalities on a 3D model of fiber tracts in people with BD (N=38) and healthy controls (N=49), and investigate along-tract white matter (WM) microstructural differences between these groups. Using the BUAN pipeline, BD was associated with lower mean Fractional Anisotropy (FA) in fronto-limbic and interhemispheric pathways and higher mean FA in posterior bundles relative to controls. BUAN combines tractography and anatomical information to capture distinct along-tract effects on WM microstructure that may aid in classifying diseases based on anatomical differences.

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Nabulsi, L., Chandio, B. Q., Dhinagar, N., Laltoo, E., McPhilemy, G., Martyn, F. M., Hallahan, B., McDonald, C., Thompson, P. M., Cannon, D. M.. 2023-03-10. Along-Tract Statistical Mapping of Microstructural Abnormalities in Bipolar Disorder: A Pilot Study. https://doi.org/10.1101/2023.03.07.531585

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