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マツトモ ノリカズ
松友 紀和 所属 川崎医療福祉大学 医療技術学部 診療放射線技術学科 職種 特任准教授 |
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| 論文種別 | 原著 |
| 言語種別 | 英語 |
| 査読の有無 | 査読あり |
| 表題 | Optimization of Number of Iterations as a Reconstruction Parameter in Bone SPECT Imaging Using a Novel Thoracic Spine Phantom. |
| 掲載誌名 | 正式名：Journal of nuclear medicine technology 略 称：J Nucl Med Technol ISSNコード：15355675/00914916 |
| 掲載区分 | 国外 |
| 巻・号・頁 | 49(2),pp.143-149 |
| 著者・共著者 | Mitsuha Fukami, Norikazu Matsutomo, Tomoaki Yamamoto |
| 発行年月 | 2021/06 |
| 概要 | The aim of this study was to optimize the number of iterations in bone SPECT imaging using a novel thoracic spine phantom (ISMM phantom). Methods: The quality and quantitative accuracy of bone SPECT images were evaluated by changing the number of iterations and the size of the hot spot in the phantom. True SUVs in the vertebra, tumor, and background parts were 9.8, 52.2, and 1.0, respectively. The phantom image was reconstructed using the ordered-subset expectation-maximization algorithm with CT-based attenuation correction, scatter correction, and resolution recovery; the number of ordered-subset expectation-maximization subsets was fixed at 10, with iterations ranging from 1 to 40. Full width at half maximum, percentage coefficient of variation, contrast ratio for the sphere and background (contrast), and recovery coefficient were evaluated as a function of the number of iterations for a given number of subsets (10) using the reconstructed images. In addition, SUVmax, SUVpeak, and SUVmean were calculated with various numbers of iterations for each sphere (13, 17, 22, and 28 mm) simulating a tumor. Results: Full width at half maximum decreased as the number of iterations was increased, and full width at half maximum converged uniformly when the number of iterations exceeded 10. The percentage coefficient of variation increased as the number of iterations was increased. Recovery coefficient decreased with decreasing sphere size. Contrast and all SUVs increased as the number of iterations was increased, and contrast and all SUVs converged uniformly when the number of iterations exceeded 5 and 10, respectively, for all sphere sizes. When the SUV was defined as the converged value for 10 iterations in the 28-mm sphere, the converged values of SUVmax, SUVpeak, and SUVmean were 75.1, 66.5, and 55.6, respectively. The relative error in the converged values for SUVmax, SUVpeak, and SUVmean were 43.8%, 27.3%, and 7.2% of the true value (52.2); all SUVs were overestimated. C |
| DOI | 10.2967/jnmt.120.253534 |
| PMID | 33361180 |