Sharif Digital Repository

The configuration of landmarks is an important issue in minimizing the target registration error (TRE). In this paper the effect of different landmark configurations on the accuracy of pedicle screw placement during image guided spine surgery (IGSS) is investigated. Since the spine is deformed in intra-operative conditions compared to the preoperative situation, an accurate alignment of each vertebra is crucial to compensate for the deformation. CT compatible markers are placed over anatomical landmarks which are feasible and routinely used in surgical procedures. The TRE is obtained directly for the markers which are placed on the right and left pedicle of the vertebra. The estimated TRE... 

Image based registration of rigid objects has been frequently addressed in the literature to obtain an object's motion parameters. In this paper, a new approach of joint segmentation-rigid registration, within the variational framework of the phase field approximation of the Mumford-Shah's functional, is proposed. The defined functional consists of two Mumford-Shah equations, extracting the discontinuity set of the reference and target images due to a rigid spatial transformation. Multiscale minimization of the proposed functional after finite element discretization provided a sub-pixel, robust algorithm for edge extraction as well as edge based rigid registration. The implementation...