Author : Jef Vandemeulebroucke
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (81 download)
Book Synopsis Lung Motion Modelling and Estimation for Image Guided Radiation by : Jef Vandemeulebroucke
Download or read book Lung Motion Modelling and Estimation for Image Guided Radiation written by Jef Vandemeulebroucke and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The principal aim of this work is to provide methodological contributions for the quantification, characterization and representation of lung motion, in order to facilitate its inclusion in the radiotherapy treatment process. We describe a method for automatically extracting a motion mask, which divides the thorax into moving and less-moving regions. By providing an interface where sliding motion occurs, the discontinuity in the motion fields is preserved and registration is facilitated. Stronger smoothness constraints can be applied for each region separately while maintaining matching accuracy. Next, a spatio-temporal registration framework for respiratory-correlated imaging of the lungs is developed. A spatial transformation based on B-splines is extended to the temporal domain by coupling it to a cyclic trajectory model with suitable smoothness constraints. The obtained deformation model is shown to be capable of accurately representing respiratory motion while using a more compact and restrictive parameterisation. By enforcing the temporal coherence of the deformation across the breathing cycle, robustness to artefacts of subsequent deformable registration is improved. Finally, we investigated the feasibility of performing respiratory motion estimation from a cone-beam projection sequence. A prior is introduced in the form of a patient-specific model built from a previously acquired 4D~CT image. Motion estimation is accomplished by comparing the cone-beam projection sequence to projection views of the patient model. A semi-global optimisation approach is utilized, considering the entire breathing cycle and providing smooth motion estimates per cycle.