Jensen Laboratory

Formula showing that the fiber orientation density function is proportional to the inverse Funk transform of the diffusion MRI signal.
 

Dr. Jensen’s research relates to developing and applying MRI technology. A major focus is employing diffusion MRI to characterize brain microstructure. For example, the Jensen lab has proposed a diffusion MRI method known as fiber ball imaging for measuring the distribution of axon orientations in vivo. As a part of several ongoing collaborations, this method and others are being used in the study of a variety of diseases including Alzheimer’s, stroke, and addiction.



Jensen research
Research 

The Jensen Lab develops novel MRI methods and applies them to the study of neuropathologies. In particular, diffusion MRI (dMRI) is used in a variety of ways to assess and quantify microstructural properties of brain. This enables microscale information for both white and gray matter to be obtained noninvasively and efficiently throughout the entire brain. The Jensen Lab closely collaborates with several other research groups in using dMRI to investigate several neurological and psychiatric diseases such as Alzheimer’s disease, stroke, and addiction.

Alzheimer’s Disease
The Jensen Lab (in collaboration with Dr. Fatima Falangola) is investigating the ability of advanced dMRI methods to detect subtle changes in brain microstructure for 3xTg-AD mice, which develop both beta-amyloid plaques and neurofibrillary tangles, the two primary hallmarks of Alzheimer’s pathology. The mice are being scanned longitudinally from 2 months of age up until 18 months of age in order to follow the full course of disease progression. The overall goal of this project is to demonstrate the sensitivity of dMRI in detecting AD pathology and its response to drug interventions at early stages in the disease.

Fiber Ball Imaging
A single MRI voxel from white matter has as many as one million individual axons. Typically, these are arranged in complex geometrical patterns that can be quantified by the fiber orientation density function (fODF). Remarkably, using dMRI it is possible to measure the fODF in vivo. The fODF is used both for white matter fiber tractography and in formulating microstructural models that help with the interpretation of dMRI data. However, established methods for estimating the fODF are fairly crude. The Jensen Lab is developing a new approach called fiber ball imaging that takes advantage of theoretical insights and advances in MRI scanner technology with the goal of obtaining accurate high resolution fODF measurements. Such high fidelity fODFs may provide novel biomarkers of disease and aging.

Water Exchange Imaging
The cellular compartments within the brain are constantly exchanging water. This process is essential for maintaining brain homeostasis and can be altered by disease processes. MRI provides a noninvasive method of assessing water exchange, but standard approaches do not fully take into account the complexity of brain tissue microstructure and consequently yield inconsistent results. Recently, our lab has been developing a new MRI method for quantifying water exchange in the brain that aims to overcome this limitation.


Team:
Jens H. Jensen, Ph.D.
Professor, Departments of Neuroscience and Radiology
Director, Center for Biomedical Imaging
jense@musc.edu

Biography: Dr. Jensen is a professor in the Department of Neuroscience (primary appointment) and in the Department of Radiology (secondary appointment). He also serves as the director of the Center for Biomedical Imaging. Before moving to MUSC in 2011, Dr. Jensen was a faculty member in the Department of Radiology of the New York University School of Medicine from 1993-2011. Dr. Jensen holds a B.S. degree in physics from Caltech and a Ph.D. in physics from Princeton University. He did postdoctoral work at UC Santa Barbara (CA), University of Copenhagen (Denmark), and University of Maryland (MD).


M. Fatima Falangola, M.D., Ph.D.
Research Assistant Professor
Associate Director of Preclinical Imaging,
Center for Biomedical Imaging
falangol@musc.edu

Biography: Dr. Falangola is a research assistant professor in the Department of Neuroscience. She also serves as an associate director of the Center for Biomedical Imaging. She is trained in neuropathology and has extensive experience in the application of neuroimaging to the study of aging and neurological disease.


Hunter Moss, Ph.D.
Postdoctoral Fellow
mossh@musc.edu

Biography: Hunter is interested in applying advanced neuroimaging methods, including diffusion MRI and magnetic resonance spectroscopy, to the assessment of aging and Alzheimer’s Disease.


Josh Voltin, B.S.
Research Specialist
voltin@musc.edu

Biography: Josh uses a variety of image processing and statistical methods in the analysis of MRI data for both human and animal research studies. He is also the technologist responsible for operating the 7T preclinical MRI system managed by the Center for Biomedical Imaging.


Jensen Laboratory Recent Publications (2020-present):
Jensen JH. Diffusional kurtosis time dependence and the water exchange rate for the multi-compartment Kärger model. Magn Reson Med. 2024; 91(3):1122-1135. PMID: 37957820

Voltin J, Nunn LM, Watson Z, Brasher ZE, Adisetiyo V, Hanlon CA, Nietert PJ, McRae-Clark AL, Jensen JH. Comparison of three magnetic resonance imaging measures of brain iron in healthy and cocaine use disorder participants. NMR Biomed. 2024; 37(3):e5072. PMID: 38009303

Falangola MF, Dhiman S, Voltin J, Jensen JH. Quantitative microglia morphological features correlate with diffusion MRI in 2-month-old 3xTg-AD mice. Magn Reson Imaging. 2023; 103:8-17. PMID: 37392805

Jensen JH, Voltin J, Nie X, Dhiman S, McKinnon ET, Falangola MF. Comparison of two types of microscopic diffusion anisotropy in mouse brain. NMR Biomed. 2023; 36:e4816. PMID: 35994169

Moss HG, Benitez A, Jensen JH. Optimized rectification of fiber orientation density function with background threshold. Magn Reson Imaging. 2023; 95:80-89. PMID 36368495

Falangola MF, Nie X, Voltin J, Ward R, Dhiman S, Nietert PJ, Jensen JH. Brain microstructure abnormalities in the 3xTg-AD mouse - A diffusion MRI and morphology correlation study. Magn Reson Imaging. 2022; 94:48-55. PMID: 36116712

Jensen JH. Impact of intra-axonal kurtosis on fiber orientation density functions estimated with fiber ball imaging. Magn Reson Med. 2022; 88(3):1347-1354. PMID: 35436362.

Moss HG, Jensen JH. High fidelity fiber orientation density functions from fiber ball imaging. NMR Biomed. 2022; 35(1):e4613. PMID: 34510596

Falangola MF, Nie X, Ward R, Dhiman S, Voltin J, Nietert PJ, Jensen JH. Diffusion MRI detects basal forebrain cholinergic abnormalities in the 3xTg-AD mouse model of Alzheimer's disease. Magn Reson Imaging. 2021; 83:1-13. PMID: 34229088

Moss HG, Jensen JH. Optimized rectification of fiber orientation density function. Magn Reson Med. 2021; 85(1):444-455. PMID: 32710476

Falangola MF, Nie X, Ward R, McKinnon ET, Dhiman S, Nietert PJ, Helpern JA, Jensen JH. Diffusion MRI detects early brain microstructure abnormalities in 2-month-old 3×Tg-AD mice. NMR Biomed. 2020; 33(9):e4346. PMID: 32557874.

Ramanna S, Moss HG, McKinnon ET, Yacoub E, Helpern JA, Jensen JH. Triple diffusion encoding MRI predicts intra-axonal and extra-axonal diffusion tensors in white matter. Magn Reson Med. 2020; 83(6):2209-2220. PMID: 31763730.