Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, location VUMC, Amsterdam, The Netherlands.
Eur J Nucl Med Mol Imaging. 2022 Nov;49(13):4652-4660. doi: 10.1007/s00259-022-05919-1. Epub 2022 Jul 25.
Current European Association of Nuclear Medicine (EANM) Research Ltd. (EARL) guidelines for the standardisation of PET imaging developed for conventional systems have not yet been adjusted for long axial field-of-view (LAFOV) systems. In order to use the LAFOV Siemens Biograph Vision Quadra PET/CT (Siemens Healthineers, Knoxville, TN, USA) in multicentre research and harmonised clinical use, compliance to EARL specifications for F-FDG tumour imaging was explored in the current study. Additional tests at various locations throughout the LAFOV and the use of shorter scan durations were included. Furthermore, clinical data were collected to further explore and validate the effects of reducing scan duration on semi-quantitative PET image biomarker accuracy and precision when using EARL-compliant reconstruction settings.
EARL compliance phantom measurements were performed using the NEMA image quality phantom both in the centre and at various locations throughout the LAFOV. PET data (maximum ring difference (MRD) = 85) were reconstructed using various reconstruction parameters and reprocessed to obtain images at shorter scan durations. Maximum, mean and peak activity concentration recovery coefficients (RC) were obtained for each sphere and compared to EARL standards specifications. Additionally, PET data (MRD = 85) of 10 oncological patients were acquired and reconstructed using various reconstruction settings and reprocessed from 10 min listmode acquisition into shorter scan durations. Per dataset, SUVs were derived from tumour lesions and healthy tissues. ANOVA repeated measures were performed to explore differences in lesion SUV and SUV. Wilcoxon signed-rank tests were performed to evaluate differences in background SUV and SUV between scan durations. The coefficient of variation (COV) was calculated to characterise noise.
Phantom measurements showed EARL compliance for all positions throughout the LAFOV for all scan durations. Regarding patient data, EARL-compliant images showed no clinically meaningful significant differences in lesion SUV and SUV or background SUV and SUV between scan durations. Here, COV only varied slightly.
Images obtained using the Vision Quadra PET/CT comply with EARL specifications. Scan duration and/or activity administration can be reduced up to a factor tenfold without the interference of increased noise.
目前，欧洲核医学协会（EANM）研究有限公司（EARL）为常规系统制定的 PET 成像标准化指南尚未针对长轴向视野（LAFOV）系统进行调整。为了在多中心研究和协调的临床使用中使用 LAFOV 西门子 Biograph Vision Quadra PET/CT（西门子健康公司，田纳西州诺克斯维尔），本研究探讨了该系统符合 EARL 规范的 F-FDG 肿瘤成像标准。在 LAFOV 中的不同位置进行了额外的测试，并缩短了扫描时间。此外，还收集了临床数据，以进一步探索和验证在使用符合 EARL 规范的重建设置时，缩短扫描时间对半定量 PET 图像生物标志物准确性和精密度的影响。
使用 NEMA 图像质量体模在中心和 LAFOV 中的不同位置对 EARL 符合标准的体模测量进行了测量。使用各种重建参数对 PET 数据（最大环差异（MRD）=85）进行重建，并对其进行重新处理以获得较短扫描时间的图像。获得每个球体的最大、平均和峰值活性浓度恢复系数（RC），并与 EARL 标准规范进行比较。此外，对 10 名肿瘤患者的 PET 数据（MRD=85）进行了采集，并使用各种重建设置进行了重建，然后将其从 10 分钟的列表模式采集重新处理为较短的扫描时间。对于每个数据集，从肿瘤病变和健康组织中提取 SUV。采用重复测量方差分析来探讨病变 SUV 和 SUV 的差异。采用 Wilcoxon 符号秩检验来评估不同扫描时间背景 SUV 和 SUV 的差异。计算变异系数（COV）以描述噪声。
体模测量结果表明，LAFOV 中的所有位置在所有扫描时间均符合 EARL 标准。对于患者数据，符合 EARL 规范的图像在病变 SUV 和 SUV 或背景 SUV 和 SUV 之间的扫描时间没有显示出临床意义的显著差异。在此，COV 仅略有变化。
使用 Vision Quadra PET/CT 获得的图像符合 EARL 规范。扫描时间和/或放射性药物给药可以减少至原来的十分之一，而不会增加噪声干扰。
