APPARATUS AND METHOD FOR X-RAY SCATTER REDUCTION AND CORRECTION FOR FAN BEAM CT AND CONE BEAM VOLUME CT

摘要

In cone-beam volume computed tomography or similar imaging techniques, the effects of x-ray scatter are reduced through using a beam compensation filter (a bow tie filter) (610), air gap (G) technique, and an antiscatter grid (612) and corrected through the use of a beam stop array (602) combined with interpolation or convolution operation. Images are taken with the beam stop array (602), and a larger number of images are taken without the beam stop array (602). The images taken with the beam stop array (602) are spatially interpolated to derive scatter information, which is then angularly interpolated to provide as many scatter images as there are images taken without the beam stop array (602). The interpolations are performed through cubic spline interpolation or any other interpolation techniques or low-pass filtering operation (convolution operation with a selected kernel). Each scatter image is subtracted from a corresponding one of the images taken without the beam stop array (602) to provide a sequence of scatter-corrected images.