Hybridising cuckoo search algorithm for extracting the ODF maxima in spherical harmonic representation

The diffusion-weighted magnetic resonance imaging (DW-MRI) is a promising method for non-invasive investigation of anatomical connectivity in the human brain. Q-ball imaging (QBI) is a diffusion MRI reconstruction technique which has been proven very successful in resolving multiple intravoxel fibre orientations in MRI (i.e., fibre crossing) based on the standard computation of the orientation distribution function (ODF), which is a 3-dimension spherical function founded to detect the dominant fibre orientations in the underlying volume of a pixel (voxel). However, ODF still has a limitation in determining fibre directions which may be corrupted by neighbour directions. In this paper, we proposed a new method to solve the ODF problem by adapting the hybridisation of the cuckoo search algorithm (i.e., global search) and bat algorithm (i.e., local search), namely, CSBA. The performance of the method is demonstrated by experiments in both synthetic and real data.