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Abstract #3185

Diffusion Tensors from Double-PFG of the Human Brain

Carl-Fredrik Westin1, 2, Markus Nilsson3, Ofer Pasternak1, Hans Knutsson2

1Department of Radiology, BWH, Harvard Medical School, Boston, MA, United States; 2Department of Biomedical Engineering, Medical Informatics, Linkping University, Linkping, Sweden; 3Department of Medical Radiation Physics, Lund University, Lund, Sweden

In this work we estimate diffusion tensors from double-PFG diffusion MRI using two types of measurements 1) paris of gradients that are collinear, and 2) pairs of gradients that are non-collinear. It is known from angular double-PFG that compartment shape anisotropy can be measured with varying the angle between the gradient pairs. The ratio between the measurements with 90 degrees (non-collinear) and the one with 0 degrees (collinear), depends on the compartments shape anisotropy. This work provides and alternative to the model of angular double-PFG introducing two different estimation of the diffusion tensor, where the ratio between them is related to the compartment shape anisotropy.

Keywords

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