title: A complete distortion correction for MR images: II. Rectification of static-field inhomogeneities by similarity-based profile mapping.
abstract: Radiotherapy treatment planning relies on the use of geometrically correct images. This paper presents a fully automatic tool for correcting MR images for the effects of B(0) inhomogeneities. The post-processing method is based on the gradient-reversal technique of Chang and Fitzpatrick (1992 IEEE Trans. Med. Imaging 11 319-29) which combines two identical images acquired with a forward- and a reversed read gradient. This paper demonstrates how maximization of mutual information for registration of forward and reverse read gradient images allows the elimination of user interaction for the correction. Image quality is preserved to a degree not reported previously.
authors.affiliation: Cancer Research UK Clinical MR Research Group, Royal Marsden NHS Trust/Institute of Cancer Research, Downs Rd, Sutton SM2 5PT, UK. stefan.reinsberg@icr.ac.uk
authors.forename: Stefan A
authors.initials: SA
authors.lastname: Reinsberg
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Doran
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Charles-Edwards
authors.forename: Martin O
authors.initials: MO
authors.lastname: Leach
mesh_terms: D000465:Algorithms; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D010388:Pelvis / Q000033:anatomy & histology; D019047:Phantoms, Imaging; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods; D012886:Skull / Q000033:anatomy & histology