Pattern Recognition Lab, Universität Erlangen-Nürnberg, Erlangen, 91058, Germany.
Erlangen Graduate School in Advanced Optical Technologies, Erlangen, 91058, Germany.
Med Phys. 2020 Feb;47(2):552-562. doi: 10.1002/mp.13950. Epub 2020 Jan 1.
Dual-energy computed tomography (DECT) has shown great potential in many clinical applications. By incorporating the information from two different energy spectra, DECT provides higher contrast and reveals more material differences of tissues compared to conventional single-energy CT (SECT). Recent research shows that automatic multi-organ segmentation of DECT data can improve DECT clinical applications. However, most segmentation methods are designed for SECT, while DECT has been significantly less pronounced in research. Therefore, a novel approach is required that is able to take full advantage of the extra information provided by DECT.
In the scope of this work, we proposed four three-dimensional (3D) fully convolutional neural network algorithms for the automatic segmentation of DECT data. We incorporated the extra energy information differently and embedded the fusion of information in each of the network architectures.
Quantitative evaluation using 45 thorax/abdomen DECT datasets acquired with a clinical dual-source CT system was investigated. The segmentation of six thoracic and abdominal organs (left and right lungs, liver, spleen, and left and right kidneys) were evaluated using a fivefold cross-validation strategy. In all of the tests, we achieved the best average Dice coefficients of 98% for the right lung, 98% for the left lung, 96% for the liver, 92% for the spleen, 95% for the right kidney, 93% for the left kidney, respectively. The network architectures exploit dual-energy spectra and outperform deep learning for SECT.
The results of the cross-validation show that our methods are feasible and promising. Successful tests on special clinical cases reveal that our methods have high adaptability in the practical application.
能谱 CT(DECT)在许多临床应用中显示出巨大的潜力。通过结合来自两个不同能谱的信息,DECT 提供了比传统单能 CT(SECT)更高的对比度和更多的组织物质差异。最近的研究表明,DECT 数据的自动多器官分割可以改善 DECT 临床应用。然而,大多数分割方法是为 SECT 设计的,而 DECT 在研究中则明显较少。因此,需要一种新的方法,能够充分利用 DECT 提供的额外信息。
在这项工作的范围内,我们提出了四种用于自动分割 DECT 数据的三维(3D)全卷积神经网络算法。我们以不同的方式整合了额外的能量信息,并在每个网络架构中嵌入了信息融合。
使用临床双源 CT 系统采集的 45 例胸部/腹部 DECT 数据集进行了定量评估。使用五折交叉验证策略评估了六个胸部和腹部器官(左、右肺、肝、脾和左、右肾)的分割。在所有的测试中,我们分别获得了 98%的右肺、98%的左肺、96%的肝、92%的脾、95%的右肾、93%的左肾的最佳平均 Dice 系数。网络架构利用双能谱,在 SECT 上的表现优于深度学习。
交叉验证的结果表明,我们的方法是可行和有前途的。对特殊临床病例的成功测试表明,我们的方法在实际应用中具有很高的适应性。