Abstract
Despite of the significance of computed tomography (CT) images in surgery planning and guidance, CT scans are not always applicable due to high radiation exposure, particularly risky for children and youth. It is critical to reduce radiation exposure for high sensitive candidates and statistical atlas based approach has therefore been an alternative with minimal radiation exposure.
We addressed the aforementioned challenges through statistical atlas constructions, 3D atlas to 2D radiography registration to get patient-specific models with minimal radiations and multiple-objective optimisation for planning the treatments. Statistical atlas can be employed to construct the global reference map. The atlas then can be registered to a pair of intra-operative fluoroscopy images for constructing a patient-specific model. In this way, we can reduce the radiation exposure to the patients significantly. To characterise shape variations, a statistical shape atlas is constructed using Point Distribution Model, by which a mean shape, modes of shape variation and shape variation are obtained. To construct the patient specific model from the statistical atlas, 3D-2D registration is essential and a back-projected ray based 3D-2D Iterative Closest Point registration method is investigated. Then the treatment planning module for optimal insertion is investigated to avoid critical zone and unnecessary punctures.
The experiment shows the feasibility of the proposed method for atlas-based, image-guided orthopaedic interventions using minimal radiograph and optimal planning. The proposed framework can be extended to other potential applications and one example is for periacetabular osteotomy, particularly for young females which is of great importance to minimise radiation dose during surgical planning and navigation.
