Modelisation geometrique tridimensionnel peroperatoire de la colonne vertebrale a l'aide de topographie de surface: Etude de faisabilite

Idiopathic Scoliosis is a three-dimensional deformation of the spine and the trunk. Severe cases mostly required corrective surgery by spine instrumentation with osteosynthesis. Spinal surgery instrumentation used in posterior approach consists of three implantable elements: rods, hooks and screws, which induce forces to the vertebrae that involve reduction of spine deformities. The surgeon performs the drilling and the insertion of pedicle screws without any direct visual control of the course of the trajectory of the screw or crucial structures like spinal cord, nerves and blood vessels, which makes screw insertion a delicate operation. Computer assisted surgery (CAS) is aimed to help the surgeon to define his drilling strategy, which is traditionally based on empirical location and mental registration using X-rays and the visible part of posterior vertebrae surface. The most common approach used in CAS to update the three-dimensional preoperative model with the real case treated is to register it with intraoperative 3D sensor data. The goal of this master project was to evaluate the feasibility to model the spine by registering a preoperative 3D model built from CT scan images and intraoperative video images coming from a range finder (3D Capturor, Inspeck Inc, Montreal). (Abstract shortened by UMI.)