CONE-BEAM CT scanner for quantitative use

The system consists of a cone-beam computed tomography (CBCT) scanner, in which an innovative scanning geometry makes it possible to improve the precision and accuracy of quantitative evaluations in the 3D images produced. This system (ExoCT) is implemented by collimating the x-ray beam in the axial direction and oscillating the source during scanning.

How does it work?

Traditional CBCT has two inherent limitations that restrict its use in quantitative analysis. These limitations are mainly a consequence of i) the abundance of scattered radiation reaching the detector and ii) the scanning warp of the source-detector pair confined to a circular path. The proposed invention (TRL= 2) envisages a reduction in the axial extent of the X-ray beam aperture to limit this scattered radiation, and an oscillating-circular scanning orbit to compensate for the reduction in the field of view due to collimation, and to accommodate the undersampling due to the traditional circular scanning orbit. ExoCT has been shown to increase image conspicuity throughout the reconstructed field of view, where this is strongly influenced by the distance of the source in CBCT; furthermore, the proposed invention allows for a decrease in artifacts due to scattered and cone radiation, with an increase in accuracy in the estimates of physical properties.

Applications

• Computation of treatment plans in radiotherapy;
• Tissue density estimation;
• Automatic tissue segmentation;
• Radiomics;
• Detection of small lesions.

Advantages

• Decreased uncertainty in quantitative estimates;
• Increased reproducibility;
• Increased repetitiveness;
• Increased image quality.