Exact local computed tomography based on compressive sampling

摘要

A system and method for tomographic image reconstruction using truncated projection data that allows exact interior reconstruction (interior tomography) of a region of interest (ROI) based on the known sparsity models of the ROI, thereby improving image quality while reducing radiation dosage. In addition, the method includes parallel interior tomography using multiple sources beamed at multiple angles through an ROI and that enables higher temporal resolution.

主权项

1. A method for compressed sensing based interior tomography, the method comprising:
(a) obtaining a truncated local projection dataset through an interior scan that directly involves a region-of-interest (ROI) or volume-of-interest (VOI) inside an object to be reconstructed; (b) reconstructing, in a computing device, the ROI/VOI by minimizing a weighted sum of (i) a function of an Lp (0≦p≦2) image norm of a sparsifying transform of the object to be reconstructed, and (ii) a L2 norm of a difference between measured and the forward projection datasets of the object to be reconstructed, or an L2 norm of a difference between a backprojected image of differential projection data and a Hilbert transform image of the object to be reconstructed, regularizing by other available knowledge selected from the group consisting of bounds of image intensities, compact support of the object, scout views, direct current component of the object, and texture features; and (c) outputting the reconstructed ROI/VOI.