Detection of Postmortem Human Cerebellar Cortex and White Matter Pathways Using High Angular Resolution Diffusion Tractography: A feasibility study.

Division of Newborn Medicine, Department of Medicine, Children's Hospital Boston, Harvard Medical School, Boston MA, USA
NeuroImage (Impact Factor: 6.36). 12/2012; 68. DOI: 10.1016/j.neuroimage.2012.11.042
Source: PubMed


Imaging three-dimensional cerebellar connectivity using diffusion tractography is challenging because of the ubiquitous features of crossing axonal pathways within a folium as well as intersecting pathways from neighboring folia. We applied high-angular resolution diffusion imaging (HARDI) tractography to intact postmortem adult brainstem and cerebellum to examine the 3-dimensional white matter and local gray matter pathways. The middle cerebellar peduncles conveyed fibers from the rostral pons to the lateral and caudal aspects of the cerebellar hemisphere, and from the caudal pons to medial and rostral parts of the cerebellar hemisphere. In the cerebellar cortex, tractography detected tangential coherence superficially in the cerebellar cortex and revealed fibers coursing parallel to the long axis of the folia. These fibers were consistent with the location and direction of parallel fibers in the molecular layer. Crossing with these parallel fibers were tangential fibers running perpendicular to the long axis of the folia, consistent with axons othe cortical interneurons - stellate cells and basket cells. These tangential fibers within the cerebellar cortex were distinct from fibers linking the cerebellar cortex with the deep cerebellar nuclei and the brainstem. Our results show the potential for HARDI tractography to resolve axonal pathways from different neuronal elements within the cerebellar cortex, and improve our understanding of adult cerebellar neural circuitry and connectivity in both white and gray matter.

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Available from: Jeremy D Schmahmann, Oct 14, 2015
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    • "The second step would comprise a comparison between in vivo and postmortem tractography in nonhuman species followed by in vivo tractography studies in multiple subjects to address the question of inter-individual anatomical variation. In this respect, Takahashi et al. already demonstrated the ability to reconstruct the superior cerebellar peduncle in postmortem high angular resolution diffusion imaging datasets in both adults (Takahashi et al. 2013) and during developmental stages (Takahashi et al. 2014). Further, the DRTT was studied in 15 healthy subjects and was successfully reconstructed with tractography in all subjects using a 1.5 T MRI scanner (Kwon et al. 2011). "
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