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DOI:
https://doi.org/10.29384/rbfm.2026.v20.19849001876Keywords:
PortuguêsAbstract
This study conducted a comparative analysis of image quality in SPECT imaging with the radionuclide ¹⁷⁷Lu, using three different collimators (LEGP, LEHR, and MEGP). Monte Carlo simulations with the SIMIND code, combined with image reconstruction in the CASToR software, were employed to assess the impact of scattered radiation on quantitative parameters such as contrast, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR). For each collimator, three energy windows were evaluated: a 20% window centered at 113 keV, a second centered at 208 keV, and a combined window including both peaks. Results indicated that the high-resolution LEHR collimator was the most effective at preserving contrast and contour definition. The energy window centered at 208 keV proved most advantageous, offering the best balance between sensitivity and image quality, with the highest contrast and CNR values recorded. The findings emphasize the critical importance of selecting the appropriate collimator and energy window to achieve accurate ¹⁷⁷Lu imaging. However, additional studies incorporating scatter and attenuation correction methods, as well as experimental validation of the simulation results, are recommended.
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