Donald Joseph Hagler1, Nathan S. White2, Christopher J. Pung1, Carrie R. McDonald3, Eric Halgren1,4, Anders M. Dale1,4
1Radiology, UCSD, La Jolla, CA, USA; 2Cognitive Science, UCSD; 3Psychiatry, UCSD; 4Neurosciences, UCSD
Diffusion Imaging can probe microstructural changes caused by a variety of diseases and disorders. Diffusion tensor analysis, and the derived fractional anisotropy measure, is often used to quantify such changes; however, FA depends on a number of factors. We have used a multi-compartment fiber orientation distribution model to derive more sensitive and specific measures of the coherence of fiber orientations and the relative volume fraction of isotropic tissue and free water. We averaged these measures within fiber tract ROIs generated with a probabilistic-atlas based method to study differences in tissue properties associated with temporal lobe epilepsy.