^(18)F-FDG PET/CT显像中连续采集和步进采集的比较

Comparison of continuous-bed-motion and step-and-shoot acquisition modes on ^(18)F-FDG PET/CT imaging

目的比较连续采集(continuous bed motion,CBM)和步进采集(step and shoot,SS)对^(18)F-脱氧葡萄糖(fluorodeoxyglucose,FDG)正电子发射型计算机断层显像/电子计算机断层显像(positron emission tomography/computed tomography,PET/CT)图像质量和定量分析的影响。方法选择50例PET/CT受检者分别采用CBM和SS模式在Siemens Biograph Vision 600 PET/CT设备中完成躯干部图像采集,测量纵隔血池、肺、肝、肌肉、骨骼的平均标准化摄取值(mean standardized uptake value,SUV_(mean))及标准差(standard deviation,SD),并用SD来评价图像噪声,采用配对t检验或配对秩和检验及Pearson相关分析和Bland-Altman图评价两组数据之间的差异和关系。结果在先后两次扫描中,纵隔血池和肝SUV_(mean)显著降低(t=5.630和4.993,P<0.05),腰椎SUV_(mean)显著增加(t=-3.320,P<0.05),而肺和肌肉SUV_(mean)差异无统计学意义(P>0.05)。在不同进床模式中,所有组织SUV_(mean)差异均无统计学意义(t=-1.626~-0.311,P>0.05),且存在高度相关(r=0.903~0.985),Bland-Altman图显示纵隔血池、肺、肝、竖脊肌、腰椎、大腿肌肉各组织的均值差分别为-0.02(95%CI:-0.27~0.24)、-0.01(95%CI:-0.05~0.03)、0.00(95%CI:-0.19~0.18)、-0.01(95%CI:-0.08~0.06)、-0.03(95%CI:-0.28~0.22)、0.00(95%CI:-0.07~0.08)。除大腿肌肉SD差异无统计学意义(Z=-1.163,P>0.05)外,其余各组织SS_(SD)均小于CBM_(SD)(Z=-4.406、-2.856、-5.556、-2.954和-3.104,P<0.05)。结论CBM采集方案灵活,能够提供与SS相当的定量信息,是PET/CT图像采集方法的有效补充。

Objective To investigate the effects of continuous-bed-motion(CBM)and step-and-shoot(SS)acquisition modes on image quality and quantitative analysis in ^(18)F-FDG(fluorodeoxyglucose)PET/CT(positron emission tomography/computed tomography).Methods A total of 50 patients were prospectively selected and undertake PET image acquisition in Siemens Biograph Vision 600 PET/CT equipment with CBM and SS modes.Mean standardized uptake value(SUV _(mean))and standard deviation(SD)of mediastinal blood pool,lung,liver,muscle,and bone were measured,and evaluate image noise with SD.Paired t test,Paired rank sum test Pearson correlation analysis and Bland-Altman Figure were used to evaluate the difference and relationship between the data of two groups.Results In different acquisition sequences,the SUV _(mean) of mediastinal blood Pool and liver were decreased significantly(t=5.630 and 4.993,all P<0.05),the SUV _(mean) of lumbar vertebra was increased significantly(t=-3.320,P<0.05),while the SUV _(mean) of lung and muscle was not significantly different(all P>0.05).In different acquisition modes,there were no significant difference in SUV _(mean) of all tissues(t values:from-1.626 to-0.311,P>0.05),and there were high correlation with them(r values:from 0.903 to 0.985),the Bland-Altman Figure shows that the _(mean) difference of each tissues are-0.02(95%CI:-0.27 to 0.24),-0.01(95%CI:-0.05 to 0.03),0.00(95%CI:-0.19 to 0.18),-0.01(95%CI:-0.08 to 0.06),-0.03(95%CI:-0.28 to 0.22),and 0.00(95%CI:-0.07 to 0.08).Except for the SD of thigh muscle(Z=-1.163,P>0.05),the SS_(SD) of other tissues was lower than that of CBM_(SD)(Z=-4.406,-2.856,-5.556,-2.954 and-3.104,all P<0.05).Conclusion CBM is a flexible acquisition method,which can provide the same quantitative information as SS.It is an effective supplement to PET/CT image acquisition method.