The work performed from the beginning to the end of the period are as follows:
A) Establishing a focal MS rodent model
We injected lysolecithin (LPC) to induce focal demyelination in the white and deep grey matter of the rodent’s brains. Then we used myelin-sensitive bound pool fraction mapping to evaluate the myelin loss in the focal lesions. Our results confirm that LPC treatment induces focal demyelination in WM and DGM CPu and not in the saline-injected hemisphere.
B) Evaluating the MS model by multi-modal MRI
We combined multi-modal MRI approaches (advanced diffusion MRI (dMRI), quantitative MRI (qMRI), and MR spectroscopy (MRS)) to track microstructural changes caused by focal demyelination in cerebral white matter and deep grey matter.
Publication 1: Yi He (The fellow), Susana Aznar, Hartwig R. Siebner, Tim B. Dyrby, In vivo tensor-valued diffusion MRI of focal demyelination in white and deep grey matter of rodents, NeuroImage: Clinical, Volume 30, 2021,
https://doi.org/10.1016/j.nicl.2021.102675(se abrirá en una nueva ventana).
C) Setting up an acquisition pipeline of small animal fMRI
we established an acquisition pipeline of small animal fMRI, including invasive blood gas analysis, ventilator, and real-time fMRI, and then acquired high-quality fMRI in rodents.
D) Validation (Synchrotron imaging and Histology)
We have performed 2D histology and 3D synchrotron imaging in the focal demyelinating lesions to validate the microstructural imaging of MRI.
The overview of the results and their exploitation and dissemination:
During the LinkFM project, we combined in vivo tensor-valued diffusion MRI, MRS, and quantitative myelin-sensitive MRI in MS rodent models. We found that tensor-valued dMRI bears considerable potential for microstructural imaging in MS, suggesting a regional microscopic fractional anisotropy decrease may be a promising biomarker of both white and deep gray matter lesions, whereas isotropic mean kurtosis may be particularly suited in detecting gray matter lesions in MS. We published the main results in the journal NeuroImage: Clinical and disseminated the research findings through Twitter. Moreover, we presented the tensor-valued dMRI method in the 2020 ISMRM annual meeting and achieved the ISMRM awards Summa cum laude Awards (Top 5% Abstract).
