AbstractID: 8286 Title: 3D object tracking using a single perspective projection
Image guidance during endovascular intervention is predominantly provided by two-dimensional (2D) digital radiographic systems
used for vessel visualization and localization of clips and coils. This paper describes a system for three-dimensional (3D) object
tracking using a single perspective projection. In this object tracking system, a single perspective projection is obtained by a digital
fluoroscopic x-ray system, corrected for XRII distortions (±0.035mm) and mechanical C-arm shifts (±0.080mm). The tracked object
contains high-contrast markers with known relative spacing, allowing for identification and centroid calculation of these markers in
the obtained perspective projection. A least-square projection-Procrustes analysis of the marker location in the single perspective
projection is then used to determine the 3D position of the object.
The effect of nominal x-ray exposure on the 3D object localization using simulations and phantoms was investigated and 3D object
tracking results for a range of nominal exposures is shown. The error due to the least square solution is not equally distributed among
the 3 major axes and the greatest amount of error is found in the Z (or depth) direction. In order to obtain a 3D localization error of
less than ±1mm, the 2D localization precision must be better than ±0.1mm for each marker in the single perspective projection. It is
our goal to use this 3D object tracking system to fuse the position of the tracked object, the 2D perspective projection with a high
quality 3D cone-beam CT volume.