title: Towards realtime multimodal fusion for image-guided interventions using self-similarities.
abstract: Image-guided interventions often rely on deformable multimodal registration to align pre-treatment and intra-operative scans. There are a number of requirements for automated image registration for this task, such as a robust similarity metric for scans of different modalities with different noise distributions and contrast, an efficient optimisation of the cost function to enable fast registration for this time-sensitive application, and an insensitive choice of registration parameters to avoid delays in practical clinical use. In this work, we build upon the concept of structural image representation for multi-modal similarity. Discriminative descriptors are densely extracted for the multi-modal scans based on the "self-similarity context". An efficient quantised representation is derived that enables very fast computation of point-wise distances between descriptors. A symmetric multi-scale discrete optimisation with diffusion reguIarisation is used to find smooth transformations. The method is evaluated for the registration of 3D ultrasound and MRI brain scans for neurosurgery and demonstrates a significantly reduced registration error (on average 2.1 mm) compared to commonly used similarity metrics and computation times of less than 30 seconds per 3D registration.
authors: Institute of Biomedical Engineering, Department of Engineering, University of Oxford, UK. mattias.heinrich@eng.ox.ac.uk
authors: Mattias Paul
authors: MP
authors: Heinrich
authors: Oxford University Centre for Functional MRI of the Brain, UK.
authors: Mark
authors: M
authors: Jenkinson
authors: Institute of Biomedical Engineering, Department of Engineering, University of Oxford, UK.
authors: Bartlomiej W
authors: BW
authors: Papiez
authors: Department of Oncology, University of Oxford, UK.
authors: Sir Michael
authors: SM
authors: Brady
authors: Institute of Biomedical Engineering, Department of Engineering, University of Oxford, UK.
authors: Julia A
authors: JA
authors: Schnabel
mesh_terms: D000465:Algorithms; D001932:Brain Neoplasms / Q000473:pathology* / Q000601:surgery*; D003199:Computer Systems; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D064847:Multimodal Imaging / Q000379:methods*; D019635:Neurosurgical Procedures / Q000379:methods*; D010363:Pattern Recognition, Automated / Q000379:methods; D013382:Subtraction Technique; D025321:Surgery, Computer-Assisted / Q000379:methods*