Q.STATIC呼吸门控与非门控扫描肺结节的临床价值:65例前瞻性研究

目的比较Q.STATIC呼吸门控（QSRG）与非门控(UG)扫描对肺结节图像质量、定量分析的影响，评价其临床应用价值。方法本项前瞻性研究纳入2019年11月~2020年5月疑诊肺结节且同意行QSRG采集患者65例，共295个肺结节，有4例患者因持续呼吸不规律未能完成门控检查而排除。记录QSRG和UG下可测量肺结节的最大标准摄取值（SUV_max）、肿瘤代谢体积（MTV）、平均标准摄取值（SUV_mean）、主动脉弓标准差值和临床扫描时间。比较QSRG和UGPET在肺结节检出、可测量肺结节、SUV_max、MTV、信噪比（SNR）和临床扫描时间的差异。结果QSRGPET和UGPET的PET肺结节检出肺结节数、可测量肺结节数、SUV_max、MTV、SNR和扫描时间分别为295个vs 275个、196个vs 182个、6.90±4.40g/mL vs 6.64±4.28g/mL（P < 0.05）、3.23±8.01cm3 vs 3.44±8.66cm3（P < 0.05）、30.30±20.91 vs 30.22±21.97（P>0.05）、16.45±3.74min vs 13.21±3.98min（P < 0.05），单个床位QSRG增加全身扫描的时间为3min。结论QSRG不增加放射性剂量，与UG图像相比，QSRG图像肺结节检出率和可测量能力更高，SUV_max和MTV定量分析更准确，稍有所增加总扫描时间。 

Prospective study of new respiratory phase gating technique PET/CT in evaluating the value of lung nodules

ObjectiveTo compare the effect of Q.STATIC respiratory gated (QSRG) and ungated (UG) scanning on the image quality and quantitative analysis of lung nodules, and evaluate the clinical application value of QSRG.MethodsThis prospective study included patients with suspected lung nodules from November 2019 to May 2020 who agreed to undergo QSRG scan. A total of 65 patients (295 lung nodules) were enrolled, and 4 patients were excluded due to continuous irregular breathing. The maximum standard uptake value (SUV_max), tumor metabolic volume (MTV), mean standard uptake value (SUV_mean), standard deviation (SD) value of the aortic arch and clinical scan time of measurable lung nodules under QSRG and UG were recorded. The differences between QSRG and UG PET in the detection of lung nodules, measurable lung nodules, SUV_max, MTV, signal-to-noise ratio (SNR) and clinical scan time were compared. SPSS 22.0 software was used to perform Wilcoxon signed rank test.ResultsAmong QSRG PET and UG PET, the detection of lung nodules were 295 vs 275, measurable lung nodules were 196 vs 182. SUV_max were 6.90±4.40 g/mL vs 6.64±4.28 g/mL (P < 0.05). MTV were 3.23±8.01 cm3 vs 3.44±8.66 cm3 (P < 0.05). SNR were 30.30±20.91 vs 30.22±21.97 (P>0.05) and scan time were 16.45±3.74 min vs 13.21±3.98 min (P < 0.05). Single bed QSRG increased the time of whole body scan to 3 min.ConclusionQSRG did not increase the radiation dose. Compared with UG images, QSRG images had higher detection rate and measurable ability of lung nodule. The quantitative analysis of SUV_max and MTV was more accurate, and the total scanning time was slightly increased.