Jallow Ngoneh, Christian Paul, Sunderland John, Graham Michael, Hoffman John M, Nye Jonathon A
Emory University, Atlanta, Georgia.
Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah; and.
J Nucl Med. 2016 Feb;57(2):238-41. doi: 10.2967/jnumed.115.160465. Epub 2015 Nov 12.
The role of CT in PET/CT imaging includes acquisition techniques for diagnostic, anatomic localization, and attenuation correction purposes. Diagnostic reference levels of the volumetric CT dose index (CTDIvol) are available for dedicated CT procedures on selected body regions, but similar reference levels for whole-body CT used in PET/CT examinations are limited. This work reports CTDIvol values from sites that conduct whole-body oncologic PET/CT examinations and participated in the scanner validation program of the Society of Nuclear Medicine and Molecular Imaging Clinical Trials Network.
From 2010 to 2014, a total of 154 sites submitted CT acquisition parameters used in their clinical (18)F-FDG PET/CT oncology protocols. From these parameters, the CTDIvol was estimated using the ImPACT CTDI dosimetry tables. Histograms of CTDIvol values were created for each year, and descriptive statistics, including mean, median, and 75th percentile, were reported. Repeated-measures ANOVA was performed to determine whether significant differences occurred between reporting years.
A wide range of technical parameters was reported, most notably in tube current. Between 2010 and 2014, the median CTDIvol ranged from 4.9 to 6.2 mGy and the 75th percentile from 9.7 to 10.2 mGy. There was no significant change in CTDIvol between reporting years (repeated-measures ANOVA, P = 0.985).
The 75th percentile CTDIvol reported in this work was 9.8 mGy averaged over all reporting years. These data provide a resource for establishing CTDIvol reference values specific to performing CT in PET/CT whole-body examinations. The wide ranges of CT acquisition parameters reported by sites suggest that CTDIvol reference levels may be beneficial for optimization of CT protocols.
CT在PET/CT成像中的作用包括用于诊断、解剖定位和衰减校正目的的采集技术。对于选定身体部位的专用CT检查，体积CT剂量指数（CTDIvol）的诊断参考水平是可用的，但PET/CT检查中使用的全身CT的类似参考水平有限。这项工作报告了进行全身肿瘤PET/CT检查并参与核医学与分子影像学会临床试验网络扫描仪验证计划的机构的CTDIvol值。
2010年至2014年，共有154个机构提交了其临床（18）F-FDG PET/CT肿瘤学方案中使用的CT采集参数。根据这些参数，使用ImPACT CTDI剂量测定表估算CTDIvol。为每年创建CTDIvol值的直方图，并报告包括均值、中位数和第75百分位数在内的描述性统计数据。进行重复测量方差分析以确定报告年份之间是否存在显著差异。
报告了广泛的技术参数，最显著的是管电流。2010年至2014年期间，CTDIvol的中位数范围为4.9至6.2 mGy，第75百分位数范围为9.7至10.2 mGy。报告年份之间CTDIvol没有显著变化（重复测量方差分析，P = 0.985）。
这项工作中报告的所有报告年份的第75百分位数CTDIvol平均为9.8 mGy。这些数据为建立PET/CT全身检查中特定CT的CTDIvol参考值提供了资源。各机构报告的CT采集参数范围广泛，表明CTDIvol参考水平可能有助于优化CT方案。
