A novel algorithm for the morphometric assessment of radiotherapy treatment planning volumes
A novel algorithm for the morphometric assessment of radiotherapy treatment planning volumes
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DOI：
10.1259/bjr/27674581
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发表时间：
2010-01-01
影响因子：
2.6
通讯作者：
Burnet, N. G.
中科院分区：
文献类型：
--
作者：
Jena, R.;Kirkby, N. F.;Burnet, N. G.
放射治疗计划中靶区轮廓的定量评估是质量评估和教育练习的重要方面。合格指数 (CI) 是一种基于数量的统计数据，经常用于此目的。尽管 CI 相对容易理解并且可以使用大多数治疗计划系统进行计算，但它不提供有关两个体积之间形状差异的任何信息。我们提出了一种新的形态测量（基于形状的）统计数据，称为“平均一致性距离”（MDC）。对于根据参考体积进行评估的特定体积，MDC 表示体积中所有外围点必须移动的平均距离，以便实现与参考体积的完美一致。 MDC 包括与欠轮廓相关的组件（其中评估体积小于参考体积）和与过轮廓相关的组件（其中评估延伸超出参考体积）。此外，还可以使用体积误差直方图来显示有关一致性误差的逐体素信息。 MDC统计量的计算是使用三维网格搜索算法来实现的。通过使用包括理论和实际临床体积的一系列场景，我们证明了 MDC 在检测轮廓误差方面的实用性不断提高。
Quantitative assessment of target volume contouring in radiotherapy treatment planning is an important aspect of quality assessment and educational exercises. The Conformity Index (CI) is a volume-based statistic frequently used for this purpose. Although the CI is relatively simple to understand and can be calculated using most treatment planning systems, it does not provide any information on the differences in shape between the two volumes. We present a new morphometric (shape-based) statistic known as the "mean distance to conformity" (MDC). For a specific volume that is being evaluated against a reference volume, the MDC represents the average distance that all outlying points in the volume must be moved in order to achieve perfect conformity with the reference volume. The MDC comprises a component related to under-contouring (where the evaluation volume is smaller than the reference volume) and a component related to over-contouring (where the evaluation extends beyond the reference volume). Furthermore, voxel-by-voxel information on conformity errors can also be displayed using a volume-error histogram. Calculation of MDC statistics is achieved using a three-dimensional grid search algorithm. By using a range of scenarios comprising both theoretical and actual clinical volumes, we demonstrate the increased utility of the MDC for the detection of contouring errors.