title: Tissue deformation and shape models in image-guided interventions: a discussion paper.
abstract: This paper promotes the concept of active models in image-guided interventions. We outline the limitations of the rigid body assumption in image-guided interventions and describe how intraoperative imaging provides a rich source of information on spatial location of anatomical structures and therapy devices, allowing a preoperative plan to be updated during an intervention. Soft tissue deformation and variation from an atlas to a particular individual can both be determined using non-rigid registration. Established methods using free-form deformations have a very large number of degrees of freedom. Three examples of deformable models--motion models, biomechanical models and statistical shape models--are used to illustrate how prior information can be used to restrict the number of degrees of freedom of the registration algorithm and thus provide active models for image-guided interventions. We provide preliminary results from applications for each type of model.
authors.affiliation: Division of Imaging Sciences, GKT School of Medicine, King's College London, UK. david.hawkes@kcl.ac.uk
authors.forename: D J
authors.initials: DJ
authors.lastname: Hawkes
authors.forename: D
authors.initials: D
authors.lastname: Barratt
authors.forename: J M
authors.initials: JM
authors.lastname: Blackall
authors.forename: C
authors.initials: C
authors.lastname: Chan
authors.forename: P J
authors.initials: PJ
authors.lastname: Edwards
authors.forename: K
authors.initials: K
authors.lastname: Rhode
authors.forename: G P
authors.initials: GP
authors.lastname: Penney
authors.forename: J
authors.initials: J
authors.lastname: McClelland
authors.forename: D L G
authors.initials: DL
authors.lastname: Hill
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D003238:Connective Tissue / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery*; D004548:Elasticity; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008954:Models, Biological; D009068:Movement; D013382:Subtraction Technique; D025321:Surgery, Computer-Assisted / Q000379:methods*