Ahmed Shereen1, Diana Lindquist2,
Chia-Yi Kuan3
1Department of Physics, University of
Cincinnati, Cincinnati, OH, United States; 2Imaging Research
Center, Cincinnati Children's Hospital Medical Center, United States; 3Division
of Neurology, Cincinnati Children's Hospital Medical Center
Using
diffusion tensor imaging (DTI), we characterized an animal model of
leukoaraiosis, a condition caused by chronic hypoxic-hypoperfusion which
often leads to post-stroke dementia.
We observed radial diffusivity decrease in white matter, contrary to
previous findings of increases in radial diffusivity attributed to
demyelination after hypoxic-ischemia.
Further examination using electron microscopy revealed rapid
separation of myelin sheaths and protrusion of myelin-coated vesicles which
created multiple intercellular compartments to restrict radial and axial diffusion
with minimum change in fractional anisotropy.
These results suggest a biophysical mechanism behind leukoaraiosis
which may be inferred from unique patterns in DTI metrics.
Keywords