Abstract
An energy window with a gamma peak centered at 364 keV (86%) is usually used for I-131 imaging. However, the image performance indexes such as image count, scatter fraction (SF), spatial resolution (SR) obtained using a conventional gamma camera, which uses a 3/8-in sodium iodide scintillator, are poor mainly due to its low detection efficiency. In this study, we investigated the feasibility of using a higher energy peak (637 and 723 keV) for the energy window to obtain a better imaging performance compared with the conventional I-131 imaging method. GATE (v7.0), which is based on Monte Carlo method, was used for performing simulations. A clinical gamma camera, SYMBIA-T2 (Siemens), was mounted on a NaI scintillator in the simulation. A GAGG scintillator was also realized for effective detection of high energy gamma, in addition to using high energy (HE) and ultrahigh energy (UHE) collimators. We obtained I-131 planar images through the conventionally used window method (364 keV ± 10%). The high-energy gamma ray of I 131 (637 and 723 keV) have been additionally used for improving image performance. The scatter correction method was applied to images for suppressing scatter due to high-energy gamma rays. Various indexes are used for validating image performance such as SR, SF, and contrast-to-noise ratio. High-energy gamma rays could be used to increase the image counts, but the other image performances were degraded compared to the scatter-corrected 364 keV images (SF of 6.33 - 27.73%; SR of 0.93 - 6.02%). The UHE collimator was useful in obtaining a better spatial resolution and suppressing scatter components compared with the HE collimator. However, it did not exhibit a sufficient image performance to be considered as a replacement for the HE collimator. In order to use the high-energy gamma rays of I-131 (637 and 723 keV), it is necessary to design a new collimator to control penetration and improve resolution, instead of using a UHE collimator. Furthermore, scatter correction methods also need to be optimized.
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References
M. S. Kaminski, J. Estes, K. R. Zasadny, I. R. Francis, C. W. Ross et al., Blood 96, 1259 (2000).
R. L. Wahl, Semin. Oncol. 30, 31 (2003).
J. G. Rajendran, A. K. Gopal, D. R. Fisher, L. D. Durack, T. A. Gooley et al., J. Nucl. Med. 49, 837 (2008).
Z. Keidar, O. Israel and Y. Krausz, Semin. Nucl. Med. 33, 205 (2003).
S. Kohlfuerst, I. Igerc, M. Lobnig, H. J. Gallowitsch, I. Gomez-Segovia et al., Eur. J. Nucl. Med. Mol. Imaging 36, 886 (2009).
Y. K. Dewaraja, S. J. Wilderman, K. F. Koral, M. S. Kaminski and A. M. Avram, Cancer Biother Radiopharm 24, 417 (2009).
G. Sgouros, K. S. Kolbert, A. Sheikh, K. S. Pentlow, E. F. Mun et al., J. Nucl. Med. 45, 1366 (2004).
E. Rault, S. Vandenberghe, R. V. Holen, J. D. Beenhouwer, S. Staelens et al., Cancer Biother Radiopharm 22, 423 (2007).
T. G. Turkington, C. M. Laymon, R. E. Coleman and J. A. Patton, IEEE Trans. Nucl. Sci. 44, 1262 (1997).
D. Autret, A. Bitar, L. Ferrer, A. Lisbona and M. Bardiès, Cancer Biother Radiopharm 20, 77 (2005).
V. Zilioli, A. Peli, M. B. Panarotto, G. Magri, A. Alkraisheh, C. Wiefels et al., Endocrine 56, 551 (2017).
A. Cot, E. Jané, J. Sempau, C. Falcón, S. Bullich et al., IEEE Trans. Nucl. Sci. 53, 198 (2006).
Y. K. Dewaraja, M. Ljungberg and K. F. Koral, J. Nucl. Med. 41, 123 (2000).
Y. K. Dewaraja, M. Ljungberg and K. F. Koral, J. Nucl. Med. 41, 1760 (2000).
S. Jan, G. Santin, D. Strul, S. Staelens, K. Assiè, D. Autet et al., Phys. Med. Biol. 49, 4543 (2004).
K. Ogawa, Y. Harata, T. Ichihara, A. Kubo and S. Hashimoto, IEEE Trans. Med. Imaging 10, 408 (1991).
Y. Dewaraja, J. Li abd K. Koral, IEEE Trans. Nucl. Sci. 45, 3109 (1998).
G. Delpon, L. Ferrer, C. Lenta, A. Lisbona, I. Buvat et al., Cancer 94, 1224 (2002).
Y. K. Dewaraja, M. Ljungberg, A. J. Green, P. B. Zanzonico and E. C. Frey, J. Nucl. Med. 54, 2182 (2013).
C. Beijst, J. W. Kist, M. Elschot, M. A. Viergever, O. S. Hoekstra et al., J. Nucl. Med. 57, 103 (2016).
C. A. J. van Gils, C. Beijst, R. van Rooij and H. W. A. M. de Jong, Phys. Med. Biol. 61, 5166 (2016).
S. R. Cherry, J. A. Sorenson and M. E. Phelps, Physics in Nuclear Medicine 4th edition (Saunders, Philadelphia, 2012), p. 239.
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Kim, M., Bae, J.K., Hong, B.H. et al. Study on High Density Scintillators and Multi-energy Windows for Improving I-131 Gamma Image Quality: Monte Carlo Simulation Approach. J. Korean Phys. Soc. 74, 305–311 (2019). https://doi.org/10.3938/jkps.74.305
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DOI: https://doi.org/10.3938/jkps.74.305