Data from 4D Lung Imaging of NSCLC Patients

This data collection consists of images acquired during chemoradiotherapy of 20 locally-advanced, non-small cell lung cancer patients. The images include four-dimensional (4D) fan beam (4D-FBCT) and 4D cone beam CT (4D-CBCT). All patients underwent concurrent radiochemotherapy to a total dose of 64.8-70 Gy using daily 1.8 or 2 Gy fractions. 4D-FBCT images were acquired on a 16-slice helical CT scanner (Brilliance Big Bore, Philips Medical Systems, Andover, MA) as respiration-correlated CTs with 10 breathing phases (0 to 90%, phase-based binning) and 3 mm slice thickness. 4D-FBCT images were acquired during simulation, prior to therapy, and used for therapy planning. In 14 of the 20 subjects, 4D-FBCTs were also acquired on the same scanner weekly during therapy. 4D-CBCT images were acquired on a commercial CBCT scanner (On-Board Imager™, Varian Medical Systems, Inc.). An external surrogate (Real-time Position Management, Varian Medical Systems, Inc.) was integrated into the CBCT acquisition system to stamp each CBCT projection with the surrogate respiratory signal through in-house software and hardware tools. Approximately 2500 projections were acquired over a period of 8-10 minutes in half-fan mode with half bow-tie filter. The technique was 125 kVp, 20 mA, and 20 ms in a single 360° slow gantry arc. Using the external surrogate, the CBCT projections were sorted into 10 breathing phases (0 to 90%, phase-based binning) and reconstructed with an in-house FDK reconstruction algorithm. Audio-visual biofeedback was performed for all 4D-FBCT and 4D-CBCT acquisitions in all subjects. A single Radiation Oncologist delineated targets and organs at risk in all 4D-FBCT and a limited number of 4D-CBCT images, on all 10 phases per scan. Seven of the subjects had gold coils implanted as fiducial markers in or near the tumor.

本数据集包含20例局部晚期非小细胞肺癌患者放化疗期间采集的影像数据。所涉影像包括四维扇形束CT（four-dimensional fan beam CT, 4D-FBCT）与四维锥形束CT（four-dimensional cone beam CT, 4D-CBCT）。所有患者均接受同步放化疗，总照射剂量为64.8~70 Gy，采用每日1.8 Gy或2 Gy的分割剂量方案。
四维扇形束CT图像于16层螺旋CT扫描仪（Brilliance Big Bore，飞利浦医疗系统，安多弗，马萨诸塞州）上采集，属于呼吸相关性CT，采用基于时相的分箱法将呼吸周期分为10个时相（0至90%），层厚为3 mm。该类图像于治疗前的模拟阶段采集，用于制定治疗计划。在20例受试者中的14例，治疗期间每周也会在同一台扫描仪上采集四维扇形束CT图像。
四维锥形束CT图像采用商用CBCT扫描仪（On-Board Imager™，瓦里安医疗系统公司）采集。将外部呼吸替代监测系统（Real-time Position Management，瓦里安医疗系统公司）集成至CBCT采集系统，通过自研软硬件工具为每幅CBCT投影标记呼吸替代信号。扫描采用半扇束模式搭配半蝴蝶结形滤过板，在8~10分钟内采集约2500幅投影，扫描参数为125 kVp、20 mA、20 ms，单次360°慢速机架旋转扫描。通过外部呼吸替代信号，将CBCT投影按基于时相的分箱法分为10个呼吸时相（0至90%），并采用自研FDK重建算法完成图像重建。
所有受试者的全部四维扇形束CT与四维锥形束CT采集均采用视听生物反馈训练。一名放射肿瘤学家对所有四维扇形束CT图像，以及有限数量的四维锥形束CT图像的每个扫描的全部10个时相进行了靶区与危及器官的勾画。其中7例受试者在肿瘤内或肿瘤附近植入了金基准标记物（fiducial marker）作为定位标记。