School of Medicine and Surgery - University of Milan - Bicocca, Milan, Italy
Nuclear Medicine Department, ASST- Monza, San Gerardo Hospital, Monza, Italy
Curr Radiopharm. 2020;13(3):218-227. doi: 10.2174/1874471013666200317144629.
Motion artifacts related to the patient's breathing can be the cause of underestimation of the lesion uptake and can lead to missing of small lung lesions. The respiratory gating (RG) technology has demonstrated a significant increase in image quality.
The aim of this paper was to evaluate the advantages of RG technique on PET/CT performance in lung lesions. The impact of 4D-PET/CT on diagnosis (metabolic characterization), staging and re-staging lung cancer was also assessed, including its application for radiotherapy planning. Finally, new technologies for respiratory motion management were also discussed.
A comprehensive electronic search of the literature was performed by using Medline database (PubMed) searching "PET/CT", "gated" and "lung". Original articles, review articles, and editorials published in the last 10 years were selected, included and critically reviewed in order to select relevant articles.
Many papers compared Standardized Uptake Value (SUV) in gated and ungated PET studies showing an increase in SUV of gated images, particularly for the small lesions located in medium and lower lung. In addition, other features as Metabolic Tumor Volume (MTV), Total Lesion Glycolysis (TLG) and textural-features presented differences when obtained from gated and ungated PET acquisitions. Besides the increase in quantification, gating techniques can determine an increase in the diagnostic accuracy of PET/CT. Gated PET/CT was evaluated for lung cancer staging, therapy response assessment and for radiation therapy planning.
New technologies able to track the motion of organs lesion directly from raw PET data, can reduce or definitively solve problems (i.e.: extended acquisition time, radiation exposure) currently limiting the use of gated PET/CT in clinical routine.
与患者呼吸相关的运动伪影可能是低估病变摄取的原因，并可能导致小的肺部病变漏诊。呼吸门控（RG）技术已证明可显著提高图像质量。
本文旨在评估 RG 技术对肺部病变 PET/CT 性能的优势。还评估了 4D-PET/CT 对肺癌诊断（代谢特征）、分期和再分期的影响，包括其在放疗计划中的应用。最后，还讨论了用于呼吸运动管理的新技术。
通过使用 Medline 数据库（PubMed）搜索“PET/CT”、“门控”和“肺”，对文献进行全面的电子检索。选择并批判性地回顾了过去 10 年发表的原始文章、综述文章和社论，以选择相关文章。
许多论文比较了门控和非门控 PET 研究中的标准化摄取值（SUV），结果表明门控图像的 SUV 增加，特别是位于中下部肺部的小病变。此外，当从门控和非门控 PET 采集获得时，其他特征（如代谢肿瘤体积（MTV）、总病变糖酵解（TLG）和纹理特征）也存在差异。除了定量增加外，门控技术还可以提高 PET/CT 的诊断准确性。门控 PET/CT 已用于肺癌分期、治疗反应评估和放射治疗计划。
能够直接从原始 PET 数据跟踪器官病变运动的新技术，可以减少或彻底解决当前限制门控 PET/CT 在临床常规中使用的问题（例如：延长采集时间、辐射暴露）。
