Cyril POUPON (NeuroSpin/BAOBAB) will give a talk on Zoom on June 21st.
Short abstract:
The limitations of the spatial-angular resolution of diffusion-weighted MRI data available today on most high-field MRI systems are an impediment to developing a reliable model of the human structural connectome.
While the emergence of extreme field MRI systems is a promising way to increase the signal-to-noise ratio and thus spatial resolution, it is not sufficient and must be accompanied by a significant increase in the capabilities of the gradient system to jointly increase the angular resolution of the diffusion propagator and its ability to transform MRI into a virtual biopsy tool.
In the framework of the FibrAtlas project, conducted in close collaboration with the INSERM iBRAIN unit, and the Human Brain Project, conducted in close collaboration with the Institute of Neuroscience and Medicine of the Forschungszentrum Jülich, the BAOBAB/Ginkgo team of NeuroSpin has embarked on the acquisition of a unique MRI dataset by scanning a post-mortem anatomical specimen on NeuroSpin's preclinical imaging platform, which is the only one that currently fulfils the above-mentioned conditions.
During this presentation, we will show that after an acquisition campaign that lasted more than two years, the team was able to reconstruct a dataset with a spatial resolution ranging from 100 micrometers for the anatomical data to 200 micrometers for the diffusion and relaxometric data, and with an angular resolution that is out of all proportion to that conventionally obtained on a clinical imager.
The extraordinary size of the obtained big data, reaching almost a TeraByte, required a thorough review of the analysis pipelines in order to make extensive use of code parallelization techniques.
The result is now up to expectations and opens the way to mesoscopic exploration of the anatomy and connectivity of the finest brain structures inaccessible at lower resolutions. The richness of the acquired dataset also allows us to understand the cyto- and myelo-architecture of brain tissues. We will show how the reconstructed connection maps allow us to better capture the pathways of axonal fibres within the cortical ribbon or the hippocampus, allowing a more robust construction of the structural connectome in humans.