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X-ray phase-contrast imaging (XPCI) overcomes the problem of low contrast between different soft tissues achieved in conventional x-ray imaging by introducing x-ray phase as an additional contrast mechanism. This work describes a compact x-ray light source (CXLS) and compares, via simulations, the high quality XPCI results that can be produced from this source to those produced using a microfocus x-ray source. The simulation framework is first validated using an image acquired with a microfocus-source, propagation-based XPCI (PB-XPCI) system. The phase contrast for a water sphere simulating a simple cyst submersed in muscle is evaluated and the evolution of PB-XPCI signal as the object to detector distance is increased is demonstrated. The proposed design of a PB-XPCI system using the CXLS is described and simulated images of a coronary artery compared between CXLS and microfocus source PB-XPCI systems. To generate images with similar noise levels, a microfocus source would require a 3000 times longer exposure than would the CXLS. We conclude that CXLS technology has the potential to provide high-quality XPCI in a medical environment using extremely short exposure times relative to microfocus source approaches.

Purpose Demonstrate realistic simulation of grating‐based x‐ray phase‐contrast imaging (GB‐XPCI) using wave optics and the four‐dimensional Mouse Whole Body (MOBY) phantom defined with non‐uniform rational B‐splines (NURBS). Methods We use a full‐wave approach, which uses wave optics for x‐ray wave propagation from the source to the detector. This forward imaging model can be directly applied to NURBS‐defined numerical phantoms such as MOBY. We assign the material properties (attenuation coefficient and electron density) of each model part using the data for adult human tissues. The Poisson noise is added to the simulated images based on the calculated photon flux at each pixel. Results We simulate the intensity images of the MOBY phantom for eight different grating positions. From the simulated images, we calculate the absorption, differential phase, and normalized visibility contrast images. We also predict how the image quality is affected by different exposure times. Conclusions GB‐XPCI can be simulated with the full‐wave approach and a realistic numerical phantom defined with NURBS.

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