Multi-Shell Hybrid Diffusion Imaging (HYDI) at 7 Tesla in TgF344-AD Transgenic Alzheimer Rats
Year: 2015
Type: article
Abstract: Diffusion weighted imaging (DWI) is widely used to study microstructural characteristics of the brain. Diffusion tensor imaging (DTI) and high-angular resolution imaging (HARDI) are frequently used in radiology and neuroscience research but can be limited in describing the signal behavior in composite nerve fiber structures. Here, we developed and assessed the benefit of a comprehensive diffusion encoding scheme, known as hybrid diffusion imaging (HYDI), composed of 300 DWI volumes acquired at 7-Tesla with diffusion weightings at b = 1000, 3000, 4000, 8000 and 12000 s/mm2 and applied it in transgenic Alzheimer rats (line TgF344-AD) that model the full clinico-pathological spectrum of the human disease. We studied and visualized the effects of the multiple concentric "shells" when computing three distinct anisotropy maps-fractional anisotropy (FA), generalized fractional anisotropy (GFA) and normalized quantitative anisotropy (NQA). We tested the added value of the multi-shell q-space sampling scheme, when reconstructing neural pathways using mathematical frameworks from DTI and q-ball imaging (QBI). We show a range of properties of HYDI, including lower apparent anisotropy when using high b-value shells in DTI-based reconstructions, and increases in apparent anisotropy in QBI-based reconstructions. Regardless of the reconstruction scheme, HYDI improves FA-, GFA- and NQA-aided tractography. HYDI may be valuable in human connectome projects and clinical research, as well as magnetic resonance research in experimental animals.
Source: PLoS ONE
Language: English
Subfield: Radiology, Nuclear Medicine and Imaging
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $2,382
Funders: California Institute of Technology, National Institutes of Health, Beckman Institute, California Institute of Technology, National Institute on Aging, National Institute of Mental Health, National Institute of Neurological Disorders and Stroke, National Institute of Biomedical Imaging and Bioengineering, U.S. National Library of Medicine
Awards: G130320643, G1757829149, G2533166933, G3495954047, G3510044943, HARDI Mapping of Disease Effects on the Brain, G3642348494, UCLA Alzheimer's Disease Research Center, G4519566690, A Multidimensional Alzheimer's Disease Brain Atlas, Alzheimer's disease risk analyzed using population imaging genomics, G4741411087, Empowering Personalized Medicine: Integrating Imaging, Genetics, and Biomarkers, A Multidimensional Alzheimer's Disease Brain Atlas, Multidisciplinary Study of Social Behavior and Emotion in Frontotemporal Dementia, Multimodal microPET and microMRI Imaging Instrumentation, Peripheral TGF-beta Pathway Inhibitor Therapy in Alzheimer's Rats, ENIGMA Center for Worldwide Medicine, Imaging & Genomics, G6423720423, Growth factors, neuroinflammation, exercise, and brain integrity, Laboratory of Neuro Imaging Resource (LONIR), G9000210308
OpenAlex ID: W2201113688