Anisotropy of HARDI Diffusion Profiles Based on the L2-Norm
نویسندگان
چکیده
The fract ional a lliso tropy (FA ) value for Diffusion Tensor Imagillg is widely Ilsed to del.crminc t.he anisotrop~' of di fl'usioll in a given voxel. As the FA value is based on the tensor's eigenvectors it is not possible to calculate this quantity for I-IARDI dif1'tlsion profil es. III t his paper we introduce an anisotropy index for HARDI data that utilizes the L-norm as the most na tural notion of distance for square-integrable fun cl ions on the two-sphere such as HARDI d iffus ion profi les and s li.ow tha t it is the limi t of the generalized fract ional anisotropy (GFA) index. Our index is well-defined and rota tionally invariant and thus reso lves the unsat isfactory issues with the GFA index.
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Anisotropy of HARDI Diffusion Profiles based on the L-Norm
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