Els Fieremans1, Jens H. Jensen1,
Ali Tabesh1, Caixia Hu1,2, Joseph A. Helpern1,2
1Radiology, New York University School
of Medicine, New York, United States; 2Center for Advanced Brain
Imaging, Nathan S. Kline Institute, Orangeburg, NY, United States
We
develop an idealized two-compartment diffusion model of white matter suitable
for analysis with diffusional kurtosis imaging (DKI). The standard DKI
metrics are used to derive the extracellular and axonal bare diffusion
coefficients, the axonal water fraction (AWF), and tortuosity of the
extra-axonal geometry, both providing information related to axonal and
myelin density. Values for these parameters obtained for a healthy volunteer
agree well with those of prior studies. Since a DKI dataset is acquired
within a few minutes, this approach may allow for the clinical assessment of
myelin associated neuropathologies, such as multiple sclerosis and
Alzheimers disease.