Hi Live,

No, they are not equivalent by any means. MKT as was explained in the earlier question is the mean of the kurtosis tensor without any information from the diffusion tensor. MK and MKT are equivalent if and only if the diffusion tensor is fully isotropic.

The generalized FA (gFA), is analogous to the conventional FA, but unlike FA, gFA uses information from the diffusion orientation distribution function (dODF) derived from DKI using both the full diffusion and kurtosis tensors. The dODF is calculated by taking the radial projection of the diffusion displacement probability density function (dPDF) and has a weighting factor to increase sensitivity to longer diffusion displacements.

More information regarding this topic is laid out in great detail in Glenn, G. R., Helpern, J. A., Tabesh, A., & Jensen, J. H. (2015). Quantitative Assessment of Diffusional Kurtosis Anisotropy. NMR in Biomedicine, 28(4), 448–459. http://doi.org/10.1002/nbm.3271.

Thanks for the question!

-Hunter