Reconstruction of volumetric images by successive approximation in cone- beam computed tomography systems

摘要

In an improved method and apparatus for cone-beam reconstruction, a technique for mitigating reconstruction error, referred to herein as successive approximation, incrementally improves the quality of the resultant image, with an exponential decrease in error at each succession. Projection data are collected and reconstructed to form a first reconstructed image containing error due to imprecision in reconstruction. The first reconstructed image is forward projected to generate intermediate projection data which are in turn compared to the collected projection data to generate error projection data. The error projection data are reconstructed to form an error image which is, in turn, used to correct the first reconstructed image . The result is a second image which is improved in image quality. The invention is applicable to a range of computed tomography applications, including medical scanning, baggage scanning, and industrial product scanning applications.