Improved IVIM MRI of small lesions in the liver by deformable image registration with modality independent neighborhood descriptor

Abstract

Respiration-induced misalignment between multiple b-value liver DW image scan severely reduce the accuracy and stability of IVIM parameter quantification, especially in the presence of small focal lesions. These small lesions usually exhibit significantly differentintensity in different b-value images, but have similar structural information. This work introduces modality independent neighborhood descriptor to extract the structural information of small lesions for improved realignment between multiple b-value images. Preliminary results show that this structure-based registration method can well correct respiration-induced misalignment between multiple b-value images with small lesions, improve the IVIM model fitting quality, and reduce variance in quantified parameters.