Effect of Using 2mm Voxels on Observer Performance for PET Lesion Detection.
Effect of Using 2mm Voxels on Observer Performance for PET Lesion Detection.
复制标题
使用 2mm 体素对 PET 病变检测观察者性能的影响。
DOI：
10.1109/tns.2016.2518177
复制
发表时间：
2016
影响因子：
1.8
通讯作者：
Kadrmas,DanJ
中科院分区：
文献类型：
--
作者：
Morey,AMichael;Noo,Frédéric;Kadrmas,DanJ
正电子发射断层摄影（PET）图像通常以大约4 mm的平面内像素大小重建用于癌症成像。这项工作的目的是评估使用更小的像素对一般肿瘤病变检测的影响。使用来自犹他州PET病变检测数据库的实验体模数据进行了一系列观察者研究，该数据库模拟了92 kg患者的全身FDG PET癌症成像。数据包括4天内在Biograph mCT飞行时间（TOF）PET/CT扫描仪上进行的24次扫描，最多23个病变（直径）。6-16 mm）分布在体模中。图像重建与2.036毫米和4.073毫米像素使用有序子集的期望最大化（OSEM）与点扩散函数（PSF）建模和TOF。检测性能进行了评估，使用信道化的非预白化的数值观测器与本地化接收机工作特性（LROC）分析。然后分析肿瘤定位性能和LROC曲线下面积作为像素大小的函数。在所有情况下，有像素的图像比有像素的图像提供更高的检测性能。较小像素的改善程度大于PSF建模为这些数据提供的改善程度，并且提供了使用TOF的大约一半的好处。关键结果由两名人类观察员确认，他们读取了测试数据的子集。这项研究表明，通过使用比许多中心常用的更小的体素尺寸，可以显著改善PET的肿瘤检测性能。主要缺点是重建时间和数据存储要求增加了4倍。
Positron emission tomography (PET) images are typically reconstructed with an in-plane pixel size of approximately 4 mm for cancer imaging. The objective of this work was to evaluate the effect of using smaller pixels on general oncologic lesion-detection. A series of observer studies was performed using experimental phantom data from the Utah PET Lesion Detection Database, which modeled whole-body FDG PET cancer imaging of a 92 kg patient. The data comprised 24 scans over 4 days on a Biograph mCT time-of-flight (TOF) PET/CT scanner, with up to 23 lesions (diam. 6–16 mm) distributed throughout the phantom each day. Images were reconstructed with 2.036 mm and 4.073 mm pixels using ordered-subsets expectation-maximization (OSEM) both with and without point spread function (PSF) modeling and TOF. Detection performance was assessed using the channelized non-prewhitened numerical observer with localization receiver operating characteristic (LROC) analysis. Tumor localization performance and the area under the LROC curve were then analyzed as functions of the pixel size. In all cases, the images withpixels provided higher detection performance than those withpixels. The degree of improvement from the smaller pixels was larger than that offered by PSF modeling for these data, and provided roughly half the benefit of using TOF. Key results were confirmed by two human observers, who read subsets of the test data. This study suggests that a significant improvement in tumor detection performance for PET can be attained by using smaller voxel sizes than commonly used at many centers. The primary drawback is a 4-fold increase in reconstruction time and data storage requirements.