A Framework for Comparison and Evaluation of Nonlinear Intra-Subject Image Registration Algorithms Martin Urschler, Stefan Kluckner, Horst Bischof Institute for Computer Graphics and Vision, Graz, University of Technology, Austria
We claim: Standardizing Evaluation Protocols at least as important as Developing Novel Methods! -> Put framework to discussion: - Open-source community effort - Instantiate framework by showing sample evaluation Presented algorithm at last years MICCAI. Nonlinear Image Registration
„ Find a deformable mapping h(x) aligning moving and fixed image such that a defined similarity criterium is minimized.“
h(x) Base Illustration taken from ITK Software Guide. SSD, NCC, Mutual Information, … B-Spline, Thin-Plate Spline, Def Field, … Gradient Descent, BFGS, … Intensity-Based, Feature-Based, …
Medical Applications of Nonlinear Image Registration
Anatomy & Function
Correction of Motion Artifacts
Studies of Shape Variation
Segmentation by Atlas Registration
Lung Perfusion for Pulmonary Embolism Detection [Wildberger et al.] Validation Study: Atlas-based Brain Volume Segmentation from MRI Images [Ng02] – taken from ITK Documentation Inter- & Intra-Modality Inter- & Intra-Subject No Ground Truth or Gold Standards Highly Ill-Posed How should we reach clinical acceptance?
Related Work on Evaluation (Frameworks) There exist some good ideas for evaluation in (Medical) Computer Vision! VALMET Segmentation Evaluation [Gerig et al] Community would benefit from open-source implementation! MICCAI 2007 Segmentation Challenge Workshop Multi-View 3D Reconstruction [Seitz et al] Stereo Reconstruction [Scharstein et al] Middlesbury Retrospective Evaluation of Intersubject Brain Registration [Hellier et al] Retrospective Rigid Registration Evaluation Project [West et al] NIREP (Inter-subject Brain-Registration Evaluation) [Christensen et al] Validation of Nonrigid Image Registration Using FEM [Schnabel et al] Segmentations are compared!