While optical colonoscopy (OC) is still considered the gold standard and is necessary for performing polypectomies when required, virtual colonoscopy (VC) systems present certain advantages over the traditional OC, such as increased coverage of the colon wall and the ability to utilize computer-aided detection (CAD) techniques. In order to leverage the abilities provided by both OC and VC, a me...

The automatic co-registration of point clouds, representing 3D surfaces, is a relevant problem in 3D modeling. We treat the problem as least squares matching of overlapping surfaces. The surface may have been digitized/sampled point by point using a laser scanner device, a photogrammetric method or other surface measurement techniques. Our proposed method estimates the transformation parameters...

The goal of anomalous change detection (ACD) is to identify what unusual changes have occurred in a scene, based on two images of the scene taken at different times and under different conditions. The actual anomalous changes need to be distinguished from the incidental differences that occur throughout the imagery, and one of the most common and confounding of these incidental differences is d...

This paper presents a mathematical framework for dealing with area-based image co-registration problems in a generic and modular way. Based on this framework an efficient implementation is devised allowing “plug & play” support for a whole gamut of geometric transformations, image similarity measures (criteria) and optimisation methods. A typical drawback of area-based methods is the exhaustive...

Frame hyperspectral sensors, in contrast to push-broom or line-scanning ones, produce hyperspectral datasets with, in general, better geometry but with unregistered spectral bands. Being acquired at different instances and due to platform motion and movements (UAVs, aircrafts, etc.), every spectral band is displaced and acquired with a different geometry. The automatic and accurate registration...

BACKGROUND Simultaneous real-time fluoroscopic and nuclear imaging could benefit image-guided (oncological) procedures. To this end, a hybrid modality is currently being developed by our group, by combining a c-arm with a gamma camera and a four-pinhole collimator. Accurate determination of the system parameters that describe the position of the x-ray tube, x-ray detector, gamma camera, and col...

A method for the automatic co-registration of 3D surfaces is presented. The method utilizes the mathematical model of Least Squares 2D image matching and extends it for solving the 3D surface matching problem. The transformation parameters of the search surfaces are estimated with respect to a template surface. The solution is achieved when the sum of the squares of the 3D spatial (Euclidean) d...

Brain shift, i. e. the change in configuration of the brain after opening the dura mater, is a key problem in neuronavigation. We present an approach to co-register intra-operative microscope images with preoperative MRI data to adapt and optimize intra-operative neuronavigation. The tools are a robust classification of sulci on MRI extracted cortical surfaces, guided user marking of most promi...

OBJECTIVE Positron emission tomography (PET)/CT scans can improve target definition in radiotherapy for non-small cell lung cancer (NSCLC). As staging PET/CT scans are increasingly available, we evaluated different methods for co-registration of staging PET/CT data to radiotherapy simulation (RTP) scans. METHODS 10 patients underwent staging PET/CT followed by RTP PET/CT. On both scans, gross...

OBJECTIVE The combination of brain stimulation by transcranial magnetic stimulation (TMS) and simultaneous electroencephalographic (EEG) recording has the potential to be of great value for understanding human brain functions. Recording EEG during TMS can be technically challenging because TMS induces a very strong electrical field that can saturate recording amplifiers for a long duration. Adv...