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How many projections to measure in x-ray fluorescence tomography vs the spatial resolution? 


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In X-ray fluorescence tomography (XFCT), the number of projections required for measurement impacts the spatial resolution of the imaging. Larsson et al. developed a laboratory XFCT system with high spatial resolution (sub-100 μm) and decreased scan times, utilizing a filtered back-projection method for image reconstruction . Li et al. compared reconstruction algorithms for X-ray luminescence optical tomography (XLOT) and found that XLOT-EP required fewer projections for accurate reconstructions, showing less dependence on scan depth compared to conventional FBP . Additionally, Shaker et al. demonstrated in vivo XFCT imaging with spatial resolution in the 200-400 μm range, emphasizing the importance of optimizing radiation dose and exposure times for high-resolution imaging in longitudinal studies . Therefore, optimizing the number of projections in XFCT plays a crucial role in achieving high spatial resolution imaging.

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X-ray fluorescence tomography requires multiple projections for high spatial resolution, enabling in vivo longitudinal imaging with 200-400 μm resolution using molybdenum nanoparticles.
In few-view computed tomography, measuring four projections yields a spatial resolution of approximately 1.5 mm, as shown in the study using algebraic reconstruction techniques.
Three angular projections and a 20-detector ring are sufficient for X-ray fluorescence tomography imaging, achieving a spatial resolution capable of reconstructing targets as small as 0.25 mm.
In x-ray luminescence optical tomography, two orthogonal projections are sufficient for reconstruction, offering high spatial resolution with minimal depth dependency compared to conventional methods.
In X-ray fluorescence tomography, 100 projections are typically measured to achieve high spatial resolution of sub-100 μm, as discussed in the research paper.

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