| Intraoperative brain shift limits the usefulness of image-guided neurosurgery systems (IGNS), which are based on preoperative images. Methods that are being developed to address this problem need intraoperative measurements as input. In this chapter, we present an intraoperative surface shift measurement technique that relies on a tracked 3D laser range scanner. This scanner acquires both 3D range data and 2D images, which are co-registered. We compare two methods to derive displacements at every point in the field of view. The first one relies on the registration of the 2D images; the second relies on the direct 3D registration of the 3D range data. Our results, based on five data sets, show that the 2D method is preferable. |
