Spatial resolution improvement in computer tomography (CT) using iterative reconstruction

摘要

Spatial resolution is substantially improved by simulating a system blur kernel including an angle variable in the forward projection during a predetermined iterative reconstruction technique. The iterative reconstruction acts as a deconvolution, which overcomes certain restrictions of system optics. In general, resolution is substantially improved with cone beam and helical data without a large increase in noise.

主权项

1. A method of improving spatial resolution in iteratively reconstructed image volume, comprising the steps of:
a) obtaining an image estimate from the measured data; b) forward projecting the image estimate using at least a single ray to generate reprojected data; c) applying to the reprojected data at least an angularly variant low pass filter to generate processed data; d) determining a difference between the processed data and the measured data; e) updating the image estimate based upon the difference to generate an updated image; and f) iterate the steps b) through e) using the updated image as the image estimate in the step b).