PDF(Pubmed)
Abstract：
UNASSIGNED: Differences in the contours created during magnetic resonance imaging-guided online adaptive radiotherapy (MRgOART) affect dose distribution. This study evaluated the interobserver error in delineating the organs at risk (OARs) in patients with pancreatic cancer treated with MRgOART. Moreover, we explored the effectiveness of drugs that could suppress peristalsis in restraining intra-fractional motion by evaluating OAR visualization in multiple patients.
UNASSIGNED: This study enrolled three patients who underwent MRgOART for pancreatic cancer. The study cohort was classified into three conditions based on the MRI sequence and butylscopolamine administration (Buscopan): 1, T2 imaging without butylscopolamine administration; 2, T2 imaging with butylscopolamine administration; and 3, multi-contrast imaging with butylscopolamine administration. Four blinded observers visualized the OARs (stomach, duodenum, small intestine, and large intestine) on MR images acquired during the initial and final MRgOART sessions. The contour was delineated on a slice area of ±2 cm surrounding the planning target volume. The dice similarity coefficient (DSC) was used to evaluate the contour. Moreover, the OARs were visualized on both MR images acquired before and after the contour delineation process during MRgOART to evaluate whether peristalsis could be suppressed. The DSC was calculated for each OAR.
UNASSIGNED: Interobserver errors in the OARs (stomach, duodenum, small intestine, large intestine) for the three conditions were 0.636, 0.418, 0.676, and 0.806; 0.725, 0.635, 0.762, and 0.821; and 0.841, 0.677, 0.762, and 0.807, respectively. The DSC was higher in all conditions with butylscopolamine administration compared with those without it, except for the stomach in condition 2, as observed in the last session of MR image. The DSCs for OARs (stomach, duodenum, small intestine, large intestine) extracted before and after contouring were 0.86, 0.78, 0.88, and 0.87; 0.97, 0.94, 0.90, and 0.94; and 0.94, 0.86, 0.89, and 0.91 for conditions 1, 2, and 3, respectively.
UNASSIGNED: Butylscopolamine effectively reduced interobserver error and intra-fractional motion during the MRgOART treatment.
UNASSIGNED: This study enrolled three patients who underwent MRgOART for pancreatic cancer. The study cohort was classified into three conditions based on the MRI sequence and butylscopolamine administration (Buscopan): 1, T2 imaging without butylscopolamine administration; 2, T2 imaging with butylscopolamine administration; and 3, multi-contrast imaging with butylscopolamine administration. Four blinded observers visualized the OARs (stomach, duodenum, small intestine, and large intestine) on MR images acquired during the initial and final MRgOART sessions. The contour was delineated on a slice area of ±2 cm surrounding the planning target volume. The dice similarity coefficient (DSC) was used to evaluate the contour. Moreover, the OARs were visualized on both MR images acquired before and after the contour delineation process during MRgOART to evaluate whether peristalsis could be suppressed. The DSC was calculated for each OAR.
UNASSIGNED: Interobserver errors in the OARs (stomach, duodenum, small intestine, large intestine) for the three conditions were 0.636, 0.418, 0.676, and 0.806; 0.725, 0.635, 0.762, and 0.821; and 0.841, 0.677, 0.762, and 0.807, respectively. The DSC was higher in all conditions with butylscopolamine administration compared with those without it, except for the stomach in condition 2, as observed in the last session of MR image. The DSCs for OARs (stomach, duodenum, small intestine, large intestine) extracted before and after contouring were 0.86, 0.78, 0.88, and 0.87; 0.97, 0.94, 0.90, and 0.94; and 0.94, 0.86, 0.89, and 0.91 for conditions 1, 2, and 3, respectively.
UNASSIGNED: Butylscopolamine effectively reduced interobserver error and intra-fractional motion during the MRgOART treatment.
摘要：
■在磁共振成像引导的在线自适应放射治疗（MRgOART）过程中产生的轮廓差异会影响剂量分布。这项研究评估了使用MRgOART治疗的胰腺癌患者在描绘危险器官（OAR）时的观察者间错误。此外，我们通过评估多名患者的OAR可视化,探讨了抑制蠕动的药物在抑制分数内运动方面的有效性.
■本研究招募了3名接受MRgOART治疗的胰腺癌患者。根据MRI序列和丁基东莨菪碱给药（Buscopan）将研究队列分为三种情况：1，不使用丁基东莨菪碱的T2成像；2，使用丁基东莨菪碱的T2成像；和3，使用丁基东莨菪碱的多对比成像。四名失明的观察者可视化了OAR(胃，十二指肠,小肠,和大肠）在初始和最终MRgOART会话期间采集的MR图像上。在计划目标体积周围±2cm的切片区域上描绘轮廓。骰子相似系数（DSC）用于评估轮廓。此外，在MRgOART期间在轮廓描绘过程前后采集的两幅MR图像上对OAR进行可视化,以评估蠕动是否可以被抑制.计算每个OAR的DSC。
■OAR中的观察者间错误(胃，十二指肠,小肠,三种情况的大肠）分别为0.636、0.418、0.676和0.806；0.725、0.635、0.762和0.821；以及0.841、0.677、0.762和0.807。与没有丁基东莨菪碱的所有条件相比，DSC均较高。除了在MR图像的最后一个阶段中观察到的情况2中的胃。OAR的DSC(胃，十二指肠,小肠,大肠）在轮廓检查前后分别为0.86、0.78、0.88和0.87；0.97、0.94、0.90和0.94；条件1、2和3分别为0.94、0.86、0.89和0.91。
■丁基东莨菪碱在MRgOART治疗期间有效地减少了观察者间的误差和分数内的运动。
■本研究招募了3名接受MRgOART治疗的胰腺癌患者。根据MRI序列和丁基东莨菪碱给药（Buscopan）将研究队列分为三种情况：1，不使用丁基东莨菪碱的T2成像；2，使用丁基东莨菪碱的T2成像；和3，使用丁基东莨菪碱的多对比成像。四名失明的观察者可视化了OAR(胃，十二指肠,小肠,和大肠）在初始和最终MRgOART会话期间采集的MR图像上。在计划目标体积周围±2cm的切片区域上描绘轮廓。骰子相似系数（DSC）用于评估轮廓。此外，在MRgOART期间在轮廓描绘过程前后采集的两幅MR图像上对OAR进行可视化,以评估蠕动是否可以被抑制.计算每个OAR的DSC。
■OAR中的观察者间错误(胃，十二指肠,小肠,三种情况的大肠）分别为0.636、0.418、0.676和0.806；0.725、0.635、0.762和0.821；以及0.841、0.677、0.762和0.807。与没有丁基东莨菪碱的所有条件相比，DSC均较高。除了在MR图像的最后一个阶段中观察到的情况2中的胃。OAR的DSC(胃，十二指肠,小肠,大肠）在轮廓检查前后分别为0.86、0.78、0.88和0.87；0.97、0.94、0.90和0.94；条件1、2和3分别为0.94、0.86、0.89和0.91。
■丁基东莨菪碱在MRgOART治疗期间有效地减少了观察者间的误差和分数内的运动。
