Section for Diagnostic Physics, The Intervention Centre, Oslo University Hospital, Oslo, Norway.
Acta Oncol. 2011 Aug;50(6):889-96. doi: 10.3109/0284186X.2011.583266.
(18)FDG-PET/CT imaging is well established for diagnosis and staging of lung tumors. However, more detailed information regarding the distribution of FDG within the tumor, also as a function of time after injection may be relevant. In this study we explore the feasibility of a combined dynamic and respiratory gated (DR) PET protocol.
A DR FDG-PET protocol for a Siemens Biograph 16 PET/CT scanner was set up, allowing data acquisition from the time of FDG injection. Breath-hold (BH) respiratory gating was performed at four intervals over a total acquisition time of 50 minutes. Thus, the PET protocol provides both motion-free images and a spatiotemporal characterization of the glucose distribution in lung tumors. Software tools were developed in-house for tentative tumor segmentation and for extracting standard uptake values (SUVs) voxel by voxel, tumor volumes and SUV gradients in all directions.
Four pilot patients have been investigated with the DR PET protocol. The procedure was well tolerated by the patients. The BH images appeared sharper, and SUV(max)/SUV(mean) was higher, compared to free breathing (FB) images. Also, SUV gradients in the periphery of the tumor in the BH images were in general greater than or equal to the gradients in the FB PET images.
The DR FDG-PET protocol is feasible and the BH images have a superior quality compared to the FB images. The protocol may also provide information of relevance for radiotherapy planning and follow-up. A patient trial is needed for assessing the clinical value of the imaging protocol.
（18）FDG-PET/CT 成像在诊断和分期肺部肿瘤方面已经得到广泛应用。然而，更详细的 FDG 在肿瘤内的分布信息，也可以作为注射后时间的函数，可能是相关的。在这项研究中，我们探索了一种联合动态和呼吸门控（DR）PET 方案的可行性。
为西门子 Biograph 16 PET/CT 扫描仪设置了 DR FDG-PET 方案，允许从 FDG 注射时开始采集数据。在总共 50 分钟的采集时间内，通过四次呼吸门控（BH）进行呼吸门控。因此，PET 方案提供了无运动图像和肺部肿瘤葡萄糖分布的时空特征。我们开发了内部软件工具，用于肿瘤的暂定分割，以及提取体素的标准摄取值（SUV）、肿瘤体积和所有方向的 SUV 梯度。
已经对四名试点患者进行了 DR PET 方案的研究。该程序得到了患者的良好耐受。与自由呼吸（FB）图像相比，BH 图像更清晰，SUV(max)/SUV(mean)更高。此外，肿瘤边缘的 SUV 梯度在 BH 图像中通常大于或等于 FB PET 图像中的 SUV 梯度。
DR FDG-PET 方案是可行的，BH 图像的质量优于 FB 图像。该方案还可能为放射治疗计划和随访提供相关信息。需要进行患者试验来评估成像方案的临床价值。
