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Background: The major limitation factors in single photon emission computed tomography (SPECT) detectability is the presence of scattered photons within the main photopeak.
Objective: To evaluate the impact of dual-energy window (DEW) scatter correction from Xeleris processing workstation (GE Healthcare) on the image quality including image contrast, background noise, and contrast-to-noise ratio (CNR) .
Methods: A NEMA/IEC phantom with a set of fillable spheres was used in this study. The phantom with hot lesion to warm background ratio of 10:1 were acquired with different acquisition times 20, 30, 40, and 90 seconds per frame. All projections were reconstructed with no scatter correction (NSC) and scatter correction (SC) using Xeleris vendor-supplied software.
Results: Image contrast decreased as the acquisition time increased and the larger sphere showed the greater contrast as expected. Interestingly, the contrast dropped more than half when applied SC compared with NSC. For noise, the SC resulted in an increased of image noises for all sphere sizes and acquisition times when compared with NSC. To reveal the impact of scatter on contrast and noise, the CNR was investigated, our results found that the CNR for SC was higher than NSC when acquired 30, 40, and 90 seconds per frame for small spheres (0.52 mL, 1.15 mL, and 2.57 mL), whereas in large sphere (26.52 mL and 11.49 mL), the CNRs were varied when SC or NSC applied.
Conclusions: Our results showed that the implementation of DEW scatter correction could be degraded image quality in an iodine 131 (131I) SPECT when compared with uncorrected image.
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