Quality assurance of registration of CT and MRI data sets for treatment planning of radiotherapy for head and neck cancers.
Quality assurance of registration of CT and MRI data sets for treatment planning of radiotherapy for head and neck cancers.
复制标题
DOI：
10.1120/jacmp.26.147
复制
发表时间：
2004-01-01
影响因子：
2.1
通讯作者：
Beavis, Andrew W
中科院分区：
文献类型：
--
作者：
Moore, Craig S;Liney, Gary P;Beavis, Andrew W
我们正在实施使用磁共振（MR）图像的头部和颈部放射治疗计划，这涉及到他们的注册与计算机断层扫描（CT）。注册过程的质量保证（QA）是该计划的第一步。构建体模，并确定适当的材料，以产生其组成“解剖结构”的临床相关MR T1和T2对比。我们对模型内可检测到的失真进行了表征。最后，我们评估了图像配准的准确性轮廓结构的注册/融合数据集使用治疗计划系统。每个结构的轮廓使用每一种模态，反过来，另一个盲。评估每个结构的位置、面积和周长，作为整个图像配准过程的准确性指标。通过选择合适的（3 +/- 30 kHz）接收器带宽，可以最大限度地减少MR图像中的失真效应。在磁场等中心+/-15 cm范围内，剩余失真被视为临床可接受。一致性系数（A）分析给出的值在9%的统一范围内，其中A =平方根（RaRp），Ra/p是面积/每个感兴趣结构的中心在1.8 mm内达成一致。已经开发了QA过程，以评估在头部放射治疗计划中使用多模态图像配准的准确性颈部;我们相信引进是可行和安全的。
We are implementing the use of magnetic resonance (MR) images for head and neck radiotherapy planning, which involves their registration with computed tomography (CT). The quality assurance (QA) of the registration process was an initial step of this program. A phantom was built, and appropriate materials were identified to produce clinically relevant MR T1 and T2 contrast for its constituent "anatomy". We performed a characterization of the distortion detectable within our phantom. Finally, we assessed the accuracy of image registration by contouring structures in the registered/fused data sets using the treatment planning system. Each structure was contoured using each modality, in turn, blind of the other. The position, area, and perimeter of each structure were assessed as a measure of accuracy of the entire image registration process. Distortion effects in the MR image were shown to be minimized by choosing a suitable (3 +/- 30 kHz) receiver bandwidth. Remaining distortion was deemed clinically acceptable within +/-15 cm of the magnetic field isocenter. A coefficient of agreement (A) analysis gave values to be within 9% of unity, where A = square root(RaRp) and Ra/p is the ratio of the area/perimeter of a particular structure on CT to that on MR. The center of each structure of interest agreed to within 1.8 mm. A QA process has been developed to assess the accuracy of using multimodality image registration in the planning of radiotherapy for the head and neck; we believe its introduction is feasible and safe.