A metric for evaluation of deformable image registration
A metric for evaluation of deformable image registration
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一种评估可变形图像配准的指标
DOI：
10.1117/12.2081846
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发表时间：
2015
期刊：
影响因子：
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通讯作者：
Tomohiro Iked
中科院分区：
文献类型：
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作者：
Akihiro Takemura;Hironori Kojima;Shinichi Ueda;Naoki Isomura;Kimiya Noto;Tomohiro Iked
我们提出了一个新的度量，局部不确定性（LU）的放射治疗剂量累积的变形图像配准（ESTA）的评价。LU测量在一次扫描之后图像集中每个体素的位置的不确定性。LU的基本概念是，当包括这些体素的器官变形时，聚焦体素与图像特征（诸如边缘）上的周围体素之间的距离局部不变。可以根据三个周围体素及其距离来计算在聚焦之后的聚焦体素的候选。从任意三个周围体素的若干组计算的聚焦体素的候选者的位置将变化。候选位置的变化指示聚焦体素位置的不确定性。因此，候选位置的标准偏差被视为LU值。可以在均匀信号区域中计算LU。评估这些区域的放射性活度测量结果对于剂量累积很重要。LU计算被应用于一对计算机断层扫描（CT）头部和颈部检查后，腰椎。这些CT检查用于初始放疗计划，以及治疗过程中肿瘤缩小的重新计划。我们生成的LU图像显示缩小的肿瘤区域中的高LU值和变形骨中的低LU值。我们已经提出了LU作为一个新的度量。
We propose a new metric, local uncertainty (LU) for the evaluation of deformable image registration (DIR) for dose accumulation in radiotherapy. LU measures the uncertainty of placement of each voxel in an image set after a DIR. The underlying concept of LU is that the distance between a focused voxel and a surrounding voxel on an image feature such as an edge is unchanged locally when the organ that includes these voxels is deformed. A candidate for the focused voxel after DIR can be calculated from three surrounding voxels and their distances. The positions of the candidates of the focused voxel calculated from several groups of any three surrounding voxels would vary. The variation of candidate positions indicates uncertainty in the focused voxel position. Thus, the standard deviation of candidate positions is treated as an LU value. The LU can be calculated in uniform signal regions. Assessment of DIR results in such regions is important for dose accumulation. The LU calculation was applied to a pair of computed tomography (CT) head and neck examinations after DIR. These CT examinations were for initial radiotherapy planning, and re-planning for a treatment course where the tumor underwent shrinkage during treatment. We generated an LU image showing high LU values in the shrinking tumor region and low LU values in undeformable bone. We have proposed the LU as a new metric for DIR.