Work

Scaling law for noise variance and spatial resolution in differential phase contrast computed tomography

Year: 2011

Type: article

Abstract: PURPOSE: The noise variance versus spatial resolution relationship in differential phase contrast (DPC) projection imaging and computed tomography (CT) are derived and compared to conventional absorption-based x-ray projection imaging and CT. METHODS: The scaling law for DPC-CT is theoretically derived and subsequently validated with phantom results from an experimental Talbot-Lau interferometer system. RESULTS: For the DPC imaging method, the noise variance in the differential projection images follows the same inverse-square law with spatial resolution as in conventional absorption-based x-ray imaging projections. However, both in theory and experimental results, in DPC-CT the noise variance scales with spatial resolution following an inverse linear relationship with fixed slice thickness. CONCLUSIONS: The scaling law in DPC-CT implies a lesser noise, and therefore dose, penalty for moving to higher spatial resolutions when compared to conventional absorption-based CT in order to maintain the same contrast-to-noise ratio.

Source: Medical Physics

DOI: 10.1118/1.3533718

Authors: Guang‐Hong Chen, Joseph Zambelli, Ke Li, Nicholas Bevins, Zhihua Qi

Institution: University of Wisconsin–Madison

Language: English

Topic: Advanced X-ray Imaging Techniques

Subfield: Radiation

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: bronze

Funders: National Institutes of Health, National Cancer Institute

Awards: G1742644352, G511834599, G9000198158