18F-FDG注射残留放射性活度影响因素的分析

目的分析18F-FDG药物注射过程中影响其注射后残留放射性活度的因素，以指导临床放射性药物的分装。方法收集2017年10月至12月在首都医科大学附属北京世纪坛医院核医学科行PET/CT检查的患者100例，按其注射药物的体积和放射性活度分组，用放射性活度计记录注射后注射器针筒、注射器针头、三通及头皮针残留的放射性活度以及空气中的放射性本底，并对总残留放射性活度和注射药物的放射性浓度进行曲线拟合。采用SPSS 17.0统计学软件进行正态分布检验及Spearman相关性分析。结果注射后注射器针筒、注射器针头、三通及头皮静脉针残留的放射性活度的中位数（四分位距）分别为1.59（0.93）、3.35（3.43）、1.70（0.92）MBq，总残留放射性活度为7.09（4.31）MBq；总残留放射性活度与18F-FDG注射药物的放射性浓度呈正相关（r=0.594，P < 0.01），对其进行曲线拟合，放射性浓度 < 600 MBq/mL为宜。结论对18F-FDG浓度进行稀释，降低其放射性浓度能减少总残留放射性活度，精确注射药物活度，同时能够降低对工作人员的受照剂量。

Analysis of factors affecting the residual radioactive activity of injection of 18F-FDG

ObjectiveThe factors influencing residual radioactivity in 18F-FDG injection were analyzed to guide the packing of radiopharmaceuticals.MethodsA total of 100 patients subjected to 18F-FDG PET/CT in Beijing Shijitan Hospital from October 2017 to December 2017 were analyzed. Patients were divided into different groups based on the volume and radioactivity of the radiopharmaceuticals they received. The residual radioactivity of the syringe tube, syringe needle, three-way valve, scalp needle, and background was then measured separately using a radioactivity meter. The curve of the total residual radioactivity as a function of 18F-FDG concentration was then fitted. SPSS 17.0 statistical software was used to test the normality of the data distribution, and results were analyzed by Spearman correlation.ResultsThe residual radioactivity values of the syringe needle tube, syringe needle, three-way valve, and scalp intravenous needle were 1.59(0.93), 3.35(3.43), and 1.70(0.92) MBq, respectively. The total residual radioactivity was 7.09(4.31 MBq) and significantly related to the concentration of 18F-FDG applied(r=0.594, P < 0.01). According to the fitting curve obtained, the appropriate radioactivity concentration of 18F-FDG is less than 600 MBq/mL.ConclusionsIn clinical work, appropriate dilution of the 18F-FDG injection volume and decreasing the radioactivity of pharmaceuticals can effectively reduce the total residual radioactivity of the procedure. Medical institutions should measure the appropriate dilution concentration of radioactive drugs according to the specifications of the syringes to increase the precision of injection and reduce the irradiation dose of the staff.