Martin A. Koch1,2, Jrgen Finsterbusch1,2
1Dept. of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; 2Neuroimage Nord, Hamburg - Kiel - Lbeck, Germany
Double wave vector diffusion weighting may represent a new method for assessing microscopic tissue structure. The difference between parallel and anti-parallel orientations of the gradients in two successive diffusion weighting preparations might be used to estimate the mean size of tissue pores. Calculations for short gradient pulses predict for samples with a non-uniform distribution of pore orientations that a rotation-invariant size estimate can be derived from the sum of measurements along three perpendicular orientations. It is investigated whether this holds true for in vivo experiments on brain tissue using a whole body MR system with finite gradient pulse durations.