胸部18F-FDG符合线路SPECT/CT图像质量影响因素分析

摘要

目的 通过分析胸部18F-FDG符合线路图像质量的影响因素,探讨提高符合线路图像质量的方法.方法 收集2016年12月～2017年2月于首都医科大学附属北京胸科医院行胸部18F-FDG符合线路显像患者100例.对100例胸部符合线路图像质量进行目测评价,分为优、良、差三组,图像质量优12例,良72例,差16例.同时测量肺野、胸壁、大血管及肝脏的放射性计数值及标准差(SD),分析主观评价的图像质量与客观测量值的关系.记录患者年龄、性别、身高、体重、血糖、氟脱氧葡萄糖(FDG)注射剂量、检查次序、探头1和2的放射性计数值、符合计数率、注射与扫描间隔时间,分析以上因素对图像质量的影响.结果 体重指数(BMI)、每公斤体重注射剂量及注射药物与扫描间隔时间在三组图像质量之间差异有统计学意义(均P＜ 0.01).三组图像质量中肺野放射性计数、胸壁放射性计数及肝脏放射性计数比较,差异有统计学意义(均P＜ 0.01).三组图像质量的胸壁、大血管及肝脏SD值差异有统计学意义(均P＜0.05).图像质量与符合计数率呈中度正相关(r=0.505,P＜ 0.01),与BMI呈低度负相关(r=-0.473,P＜ 0.01),与每公斤体重注射剂量呈低度正相关(r=0.343,P＜0.01).结论 主观图像质量评价与客观测量值的一致性好.BMI是影响图像质量的最主要因素,注射最佳剂量的FDG和控制合适的注射与扫描间隔时间有利于获得良好质量的图像.%Objective To discuss the method that can improve the image quality of chest 18F-FDG SPECT coincidence imaging through analysis of the factors that affect the image quality.Methods The chest coincidence imaging of 100 patients in Beijing Chest Hospital,Capital Medical University from December 2016 to February 2017 were obtained.The imaging quality was classified as excellent in 12 cases,good in 72 cases and poor in 16 cases.The radioactivity counting and the standard deviation (SD) value of lung,chest wall,main vessel and liver were recorded.The relationship of subjective image quality and the objective value was analyzed.The patients' age,gender,height,body weight,blood glucose,injected FDG dose,check order,probe 1 and 2 of the radioactivity counting and coincidence rate,injection and scanning time interval were also recorded.The influences of above factors on image quality were analyzed.Results There was a significant difference of BMI,injected FDG dose of per kilogram body weight and the time interval between the injections and scan among the three groups (all P ＜ 0.01).There was a significant difference in the radioactivity count of lung,chest wall,and liver among the three groups (all P ＜ 0.01).There was a significant difference in SD value of the chest wall,large vessels and liver among the three groups (all P ＜ 0.05).There was moderate correlation of the image quality and the coincidence rate (r =0.505,P ＜ 0.01),BMI was negatively correlated with image quality (r =-0.473,P ＜ 0.01),while the injected FDG dose of per kilogram body weight was positively correlated with image quality (r =0.343,P ＜ 0.01).Conclusion The subjective image quality evaluation is in good agreement with the objective measured values.BMI is the most important factor that affects the image quality.The best dose of injected FDG and the appropriate injection and scanning time interval are beneficial to obtain the good quality image.