Directional sensitivity of anomalous diffusion in human brain assessed by tensorial fractional motion model |
| |
| Institution: | 1. Beijing City Key Lab for Medical Physics and Engineering, Institute of Heavy Ion Physics, School of Physics, Peking University, Beijing, China;2. Center for MRI Research, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China;3. State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China;4. MR Research China, GE Healthcare, Beijing, China;5. McGovern Institute for Brain Research, Peking University, Beijing, China;6. Shenzhen Institute of Neuroscience, Shenzhen, China;1. Department of Radiology, The Ohio State University Wexner Medical Center, Columbus, OH, United States;2. Department of Mechanical Engineering, The Ohio State University, Columbus, OH, United States;3. Center for Biostatistics, Department of Biomedical Informatics, The Ohio State University, Columbus, OH, United States;4. Division of Gastroenterology, Hepatology, and Nutrition, The Ohio State University Wexner Medical Center, Columbus, OH, United States;5. Department of Internal Medicine-Division of Cardiovascular Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, United States;1. Department of Radiology, Division of Neonatology, University of Groningen and University Medical Center Groningen, Hanzeplein 1, 9713 GZ, The Netherlands;2. Department of Pediatrics, Division of Neonatology, University of Groningen and University Medical Center Groningen, Hanzeplein 1, 9713 GZ, The Netherlands;1. Department of Mathematics, University of Bergen, Bergen, Norway;2. Christian Michelsen Research, Bergen, Norway;3. Faculty of Health and Social Sciences, Western Norway University of Applied Sciences, Bergen, Norway;4. Department of Radiology, Haukeland University Hospital, Bergen, Norway;5. Department of Biomedicine, University of Bergen, Bergen, Norway;6. Department of Clinical Engineering, Haukeland University Hospital, Bergen, Norway;7. Department of Clinical Medicine, University of Bergen, Bergen, Norway;8. MedViz Research Cluster, University of Bergen, Bergen, Norway;1. Vanderbilt University Institute of Imaging Science, Nashville, TN, United States;2. Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States;3. Department of Physics and Astronomy, Vanderbilt University, Nashville, TN, United States;4. Department of Medical Physics in Radiology, German Cancer Research Center, Germany;5. Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, United States;6. Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, United States |
| |
| Abstract: | Anisotropic diffusion in the nervous system is most commonly modeled by apparent diffusion tensor, which is based on regular diffusion theory. However, the departure of diffusion-induced signal attenuation from a mono-exponential form implies that there is anomalous diffusion. Recently, a novel diffusion NMR theory based on the fractional motion (FM) model, which is an anomalous diffusion model, has been proposed. While the FM model has been applied to both healthy subjects and tumor patients, its anisotropy in the nervous system remains elusive. In this study, this issue was addressed by measuring the FM-related parameters in 12 non-collinear directions. A metric to quantify the directional deviation was derived. Furthermore, the FM-related parameters were modeled as tensors and analyzed in analogy with the conventional diffusion tensor imaging (DTI). Experimental results, which were obtained for 15 healthy subjects at 3T, exhibited pronounced anisotropy of the FM-related parameters, although the effects were smaller than the apparent diffusion coefficient (ADC). The tensorial nature for α, which is the Noah exponent in the FM model, showed behavior similar to the ADC, especially the principal eigenvector for α aligned with the dominant white matter fiber directions. The Hurst exponent H in the FM model, however, showed no correlation with the major fiber directions. The anisotropy of the FM model may provide complementary information to DTI and may have potential for tractography and detecting brain abnormalities. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
