INTERFRACTION PROSTATE ROTATION DETERMINED FROM IN-ROOM COMPUTERIZED TOMOGRAPHY IMAGES
INTERFRACTION PROSTATE ROTATION DETERMINED FROM IN-ROOM COMPUTERIZED TOMOGRAPHY IMAGES
复制标题
DOI：
10.1016/j.meddos.2010.03.002
复制
发表时间：
2011-06-01
影响因子：
1.2
通讯作者：
Duchesne, Gillian
中科院分区：
文献类型：
--
作者：
Owen, Rebecca;Kron, Tomas;Duchesne, Gillian
基准点标记物(Fm)通常被用作前列腺组间翻译的校正技术。这项研究的目的是使用两种方法来确定前列腺旋转的大小：FM坐标和前列腺和直肠的解剖边界。应用CT on rails对10例前列腺癌患者进行CT扫描(n=346)，植入3个FM。Fm坐标用于确定矢状面、横断面和冠状面的旋转，前列腺和直肠的CT轮廓用于确定沿矢状面的旋转。测试了一种基于图像子集(n=6；计划和前5个治疗CT)的自适应技术，以减少矢状面上的系统性旋转误差。系统旋转相对于FM坐标的标准差(SD)在矢状面、横面面和冠面处分别为7.6度、7.7度和5.0度！飞机。相应的随机误差SD为10.2度、15.8度和6.5度。根据前列腺和直肠轮廓确定的矢状面误差分别为10.1度(系统性)和7.7度(随机)。这些结果与从FM坐标计算的旋转没有相关性(r=-0.017；p=0.753，n=337)。根据6次CT扫描推算平均前列腺位置，系统误差可减小43%~5.6度。前列腺旋转是一个重要的误差来源，使用前列腺和直肠的解剖边界而不是FM来确定它似乎更准确，因此突出了CT图像指导的实用性。(C)2011年，由爱思唯尔公司代表美国医学剂量师协会出版。
Fiducial markers (FMs) are commonly used as a correction technique for interfraction translations of the prostate. The aim of this investigation was to determine the magnitude of prostate rotations using 2 methods: FM coordinates and the anatomical border of the prostate and rectum. Daily computed tomography (CT) scans (n = 346) of 10 prostate cancer patients with 3 implanted FMs were acquired using the CT on rails. FM coordinates were used to determine rotation in the sagittal, transverse, and coronal planes, and CT contours of the prostate and rectum were used to determine rotation along the sagittal plane. An adaptive technique based on a subset of images (n = 6; planning and first 5 treatment CTs) to reduce systematic rotation errors in the sagittal plane was tested. The standard deviation (SD) of systematic rotation from FM coordinates was 7.6 degrees, 7.7 degrees, and 5.0 degrees in the sagittal, transverse and corona! planes. The corresponding SD of random error was 10.2 degrees, 15.8 degrees, and 6.5 degrees. Errors in the sagittal plane, determined from prostate and rectal contours, were 10.1 degrees (systematic) and 7.7 degrees (random). These results did not correlate with rotation computed from FM coordinates (r = -0.017; p = 0.753, n = 337). The systematic error could be reduced by 43% to 5.6 degrees when the mean prostate position was estimated from 6 CT scans. Prostate rotation is a significant source of error that appears to be more accurately determined using the anatomical border of the prostate and rectum rather than FMs, thus highlighting the utility of CT image guidance. (C) 2011 Published by Elsevier Inc. on behalf of American Association of Medical Dosimetrists.