Marco Lawrenz1,2, Martin A. Koch1,2, Jrgen Finsterbusch1,3
1Dept. of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; 2Neuroimage Nord, Hamburg-Kiel-Lbeck, Germany; 3Neuroimage, Hamburg-Kiel-Lbeck, Germany
A theoretical approach to the double wave-vector experiment aiming at the examination of microscopic anisotropy in tissue is presented for fully restricted diffusion. A detailed analysis of the generalized tensor expression in the fourth order for long mixing times does not only hold for the characterization of non-isotropically oriented pores but deduces also a measure for microscopical anisotropy on the pore size level. Monte Carlo simulations confirm the observed signal behavior for arbitrary distributed pore populations. It is shown that the derived anisotropy parameter allows for a direct derivation of the pore anisotropy.