Accurate distortion correction scheme for digital subtraction angiography

Robust geometric distortion characterization and correction methods have been developed and validated for DSA application. A compact as well as efficient numerical parameterization technique has been used for characterizing the 3D geometric image distortion of a clinical DSA system. To some extent, the 3rd order polynomial was found to be sufficient for the parameterization of global image distortion for all rotational angles. One of the advantages of the new technique is compact in the sense that it does not require a large distortion parameter look-up table. The new method promises a potential of using less regular distributed calibration points for a complete 3D image distortion characterization of DSA system. Furthermore, two different schemes based on the pixel mapping for correcting image distortion have been successfully demonstrated yielding satisfactory results.