"Intrasubject Registration for Change Analysis in Medical Imaging"
Chapter 2 gives a general overview of image registration and describes the registration framework and software used in this thesis. The registration software was developed at the Image Sciences Institute jointly with Stefan Klein for our research projects. All experiments described in this thesis were performed with this software package, called elastix.
A first approach to tackle the rigid-nonrigid tissue problem uses adaptive filtering of the deformation field. The technique is reported in Chapter 3. Issues that remain with this approach are solved with another technique based on a local rigidity penalty term, see Chapter 4. The last technique is clinically employed for the detection of subtle changes in ground-glass opacities in the lung. The results of this study are presented in Chapter 5.
To address the problem of insufficient registration quality, in Chapter 6 the registration cost function is extended with multiple image features, instead of using image intensity only, as is commonly done.