An Approach to Identifying the Biomechanical Differences Between Intercostal Cartilage in Subjects with Pectus Excavatum and Normals in Vivo: Reconstruction and CT Registration

Pectus excavatum (PE) is a congenital chest wall deformity affecting the ribs and sternum and exhibiting a concave appearance in the anterior chest wall. In this thesis, we describe a study to investigate in vivodifferences in the pectus excavatum rib cage and outline steps using normals and pectus patients data in developing models and methods to be used in carrying out the study. We propose methods to develop reconstructed models in order to enable proper registration between data collection points (DCPs) on the 3D CT rib cage model and CT skin surface model and registration between CT surrogate models and 3D laser surface scan model with actual DCPs. A Polhemus Fastscan 3D laser scanner is used to produce a non-invasive way of quantifying the surface of the subject's chest, which can then be compared with the 3D reconstructed CT model to estimate the errors with these procedures. The results show that the minimum average error of the simulated DCPs after translation for the pectus patients (<2 >mm) is much less than that of the Visible Human male and >60% actual DCPs are distributed on the intercostal cartilages.