Meeting Banner
Abstract #3588

Pitfalls in the Reconstruction of Fibre ODFs Using Spherical Deconvolution of Diffusion MRI Data

Greg D. Parker1, Derek K. Jones1

1CUBRIC, School of Psychology, Cardiff University, Cardiff, South Glamorgan, United Kingdom

We report a previously overlooked pitfall in spherical deconvolution approaches for reconstructing fibre orientation distribution functions (fODFs) through a spherical-harmonic (SH) basis. By examining single-fibre population (fibres along the same axis) cases, we are able to uncover descriptive deficiencies in the SH representation that result in spurious fODF peaks once the assumed and actual diffusive properties of the target fibrous tissue no longer agree (e.g. local degradation through disease). Through comparison with an alternative that does not rely on spherical harmonics, we are also able to suggest a viable alternative for cases where a 'one-size-fits-all' single-fibre diffusivity assumption is inappropriate.

Keywords

ability actual adult agnostic aligned angular anisotropy apparently applied approaches arise arises assumed avoided basis better boundaries calibration causes clusters coincide cone consider considered consistent counter creating crossing deconvolution decreases defined degree degrees dell dependence derived descriptive despite development differ diffusion disease displays distributed distribution elucidate employ erroneous error errors exactly exceeds exception exhibit extract failure failures falls false fits frequency function functions harmonic healthy highest immunity important inappropriate incoming increasing independent indicate induced interpreted introduced intuitive irrespective issue kingdom known largely linear magic magnitudes marked markedly moreover noise noisy notice noticeable onset orientation outperforms overlooked pair pairing parker particularly peak peaks pertaining pitfall polynomial population positive power previously produced profiles propensity psychology published quantity reaches reconstruction recovered relationship repetitions report residuals resolution response sampling scheme school similarly simulated since south specifically spherical spurious strong substantial substantially taking target threshold tissue trajectories trajectory transitioning true tuple tuples uncertainty uniformly vectors zero