Registration of three dimensional image data to 2D-image-derived data
A method for obtaining registration of a three-dimensional image data set of an anatomical vessel with corresponding two-dimensional image data of the vessel in an X-ray imaging system, where the method comprise the user identifying two points on an anatomical vessel on at least two X-ray image planes, the user identifying two similar points on the surface of the corresponding three-dimensional anatomical image data, determining the orientation direction of the vessel from the two user identified image data surface points, determining the orientation direction of the vessel from the two points obtained from the X-ray image planes, and calculating a transformation of the three-dimensional image data to obtain a best fit registration of the direction derived from the image surface points with the direction derived from the X-ray image data points.
1. A method for obtaining registration of a three-dimensional pre-operative image data set of an anatomical vessel tree with corresponding intra-operative image data reconstructed from two-dimensional images of the vessel tree obtained in an X-ray imaging system, where the method comprises:
identifying at least one pair of points on an anatomical vessel on at least two X-ray image planes that provide an indication of vessel direction;
identifying two similar surface points on the surface of the corresponding three-dimensional anatomical image data;
using an algorithm to successively travel in a gradient direction from said similar surface points until a diametrically opposite side of the vessel is encountered, from which center points and a centerline of the vessel are determined;
determining the orientation direction of the vessel from the centerline determined from the two identified image data surface points, and determining the orientation direction of the vessel from the two points obtained from the X-ray image planes, and
determining a transformation of the three-dimensional image data to obtain a best fit registration of the direction derived from the image surface points with the direction derived from the X-ray image data points.
2. The method of claim 1 wherein the at least two X-ray image planes provide three-dimensional coordinates for the two identified points that are used to determine the centerline of the vessel and orientation direction of the anatomical vessel in the X-ray image planes.
3. The method of claim 1 wherein the determination of the orientation direction of the image data points comprises determining the center line of the vessel from first and second center points between the two surface points of the three-dimensional vessel image and the diametrically opposite side of the vessel.
4. The method of claim 3 wherein the transformation comprises a rotation matrix for aligning the direction of the three-dimensional image vessel centerline with the direction of the X-ray image vessel.
5. The method of claim 4 wherein a rotation matrix is determined based on a minimized cost function that determines a best fit rotation matrix for registering the three-dimensional data with the two dimensional X-ray image data.
6. The method of claim 5 further comprising the overlaying the three-dimensional image data onto the X-ray image planes.