肺部肿瘤标准摄入值测量的影响因素——蒙特卡罗仿真研究  

Factors Affecting Measurements of Lung Tumor Standardized Uptake Value:A Monte-Carlo Simulation Study

作　　者：贾瑞[1] 白净[1] 温凌锋[2] 冯大淦[2] 

机构地区：[1]清华大学生物医学工程系,北京100084 [2]悉尼大学信息技术学院

出　　处：《航天医学与医学工程》2009年第4期291-295,共5页Space Medicine & Medical Engineering

基　　金：国家自然科学基金项目资助(30670577);中澳科技合作特别基金(CH050131)

摘　　要：目的评价FDG-PET测量肺部肿瘤放射性比活度的有关影响因素。方法基于VHP标记图谱VIP-Man,在肺部区域添加不同直径及放射性比活度的球体肿瘤模型,对FDG-PET成像的整个过程进行高次数的蒙特卡罗(Monte-Carlo)仿真,研究肿瘤放射性比活度测量的有关影响因素。结果最大值法测量通常造成肿瘤放射性比活度的高估,且随噪声等级的提高,高估的程度也有所提高;对于较小的且真实比活度较小的肿瘤,需要进行部分容积效应的校正;对图像进行滤波后再勾画ROI可以提高结果的可重复性等。结论肿瘤放射性比活度测量的准确性和可靠性同肿瘤尺寸、重建后滤波、噪声水平、感兴趣区定义方法、PVE校正等因素都有密切的关系。Objective To evaluate the factors affecting the measurement of lung tumor activity concentration （AC） with FDG-PET. Methods High count Monte-Carlo simulations,based on VIP-Man （marked VHP atlas） added with spherical lung tumors of different diameter and activity,were performed to generate the essentially noiseless projection data for PET. The factors related with the measurement of tumor AC were evaluated. Results Using the maximum value in the tumor region of interest （ROI） generally resulted in the over-estimation of AC,and the degree of over-estimation would also increase as the noise became severer. For the small tumors with low AC,the proper partial volume correction was needed. Drawing ROI after post-reconstruction filtering could improve the reproducibility of AC measurement compared with no filtering first. Conclusion The accuracy and reliability of AC measurement depends strongly on factors including tumor size,post-reconstruction filter,noise level,ROI definition,PVE correction,etc.

关 键 词：正电子发射断层成像 放射性比活度 标准摄入值 蒙特卡罗仿真 感兴趣区 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]