A quantification strategy for missing bone mass in case of osteolytic bone lesions.
A quantification strategy for missing bone mass in case of osteolytic bone lesions.
复制标题
溶骨性骨病变病例中骨量缺失的量化策略
DOI：
10.1118/1.4828843
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发表时间：
2013
期刊：
影响因子：
3.8
通讯作者：
Bendl R
中科院分区：
文献类型：
--
作者：
Fränzle A;Bretschi M;Bäuerle T;Giske K;Hillengass J;Bendl R
目的：大多数死于乳腺癌的患者都发生了骨转移。为了了解骨转移的发病机制并分析不同骨重建疗法的治疗反应，检查了临床前动物模型。在乳腺癌中，骨转移通常具有骨破坏性。为了评估骨重塑治疗的治疗反应，必须在治疗过程中确定这些病变的体积。手动描绘缺失结构，特别是如果缺失大部分，非常耗时且不可重现。生殖是非常重要的，在治疗过程中有可比的结果。因此，需要一种计算机化的方法。此外，对于临床前研究，病变的可重复测量是必不可少的。在这里，作者提出了一种自动分割方法，用于测量丢失的骨量在临床前大鼠模型与骨转移在后腿bones.Methods的基础上的三维CT扫描：受影响的骨结构相比，健康的模型。由于在这项临床前大鼠试验中，转移仅发生在右后腿上，这是通过使用血管夹来确保的，因此作者使用左侧身体作为健康模型。左股骨用统计形状模型分割，该模型使用自动分割的髓腔进行初始化。左胫骨和腓骨使用体积增长从胫骨髓腔开始并在股骨边界停止进行分割。两个分割的掩蔽图像沿正中平面沿着镜像，并通过刚性配准手动转移到受影响骨骼的位置。根据灰度值对病变骨和健康骨模型进行比较。如果一个体素的灰度值表明在健康的模型中的骨质量和没有骨在受影响的骨，这个体素被认为是osteolytic.Results：病变分割以合理的方式完成缺失的骨结构。重建的骨体积与健康模型骨体积的平均比率vr/Vm为1.07，这表明改良骨的良好重建。结论：手动和半自动分割结果的定性和定量比较表明，将改良骨结构与健康模型进行比较可以用于以可重现的方式识别和测量缺失的骨量。
Purpose:Most of the patients who died of breast cancer have developed bone metastases. To understand the pathogenesis of bone metastases and to analyze treatment response of different bone remodeling therapies, preclinical animal models are examined. In breast cancer, bone metastases are often bone destructive. To assess treatment response of bone remodeling therapies, the volumes of these lesions have to be determined during the therapy process. The manual delineation of missing structures, especially if large parts are missing, is very time‐consuming and not reproducible. Reproducibility is highly important to have comparable results during the therapy process. Therefore, a computerized approach is needed. Also for the preclinical research, a reproducible measurement of the lesions is essential. Here, the authors present an automated segmentation method for the measurement of missing bone mass in a preclinical rat model with bone metastases in the hind leg bones based on 3D CT scans.Methods:The affected bone structure is compared to a healthy model. Since in this preclinical rat trial the metastasis only occurs on the right hind legs, which is assured by using vessel clips, the authors use the left body side as a healthy model. The left femur is segmented with a statistical shape model which is initialised using the automatically segmented medullary cavity. The left tibia and fibula are segmented using volume growing starting at the tibia medullary cavity and stopping at the femur boundary. Masked images of both segmentations are mirrored along the median plane and transferred manually to the position of the affected bone by rigid registration. Affected bone and healthy model are compared based on their gray values. If the gray value of a voxel indicates bone mass in the healthy model and no bone in the affected bone, this voxel is considered to be osteolytic.Results:The lesion segmentations complete the missing bone structures in a reasonable way. The mean ratiovr/vmof the reconstructed bone volumevrand the healthy model bone volumevmis 1.07, which indicates a good reconstruction of the modified bone.Conclusions:The qualitative and quantitative comparison of manual and semi‐automated segmentation results have shown that comparing a modified bone structure with a healthy model can be used to identify and measure missing bone mass in a reproducible way.