Division of Imaging and Applied Mathematics, Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, US Food and Drug Administration, Silver Spring, Maryland 20993, USA.
Arch Pathol Lab Med. 2011 Feb;135(2):233-42. doi: 10.5858/135.2.233.
Observer variability in digital microscopy and the effect of computer-aided digital microscopy are underexamined areas in need of further research, considering the increasing use and future role of digital imaging in pathology. A reduction in observer variability using computer aids could enhance the statistical power of studies designed to determine the utility of new biomarkers and accelerate their incorporation in clinical practice.
To quantify interobserver and intraobserver variability in immunohistochemical analysis of HER2/neu with digital microscopy and computer-aided digital microscopy, and to test the hypothesis that observer agreement in the quantitative assessment of HER2/neu immunohistochemical expression is increased with the use of computer-aided microscopy.
A set of 335 digital microscopy images extracted from 64 breast cancer tissue slides stained with a HER2 antibody, were read by 14 observers in 2 reading modes: the unaided mode and the computer-aided mode. In the unaided mode, HER2 images were displayed on a calibrated color monitor with no other information, whereas in the computer-aided mode, observers were shown a HER2 image along with a corresponding feature plot showing computer-extracted values of membrane staining intensity and membrane completeness for the particular image under examination and, at the same time, mean feature values of the different HER2 categories. In both modes, observers were asked to provide a continuous score of HER2 expression.
Agreement analysis performed on the output of the study showed significant improvement in both interobserver and intraobserver agreement when the computer-aided reading mode was used to evaluate preselected image fields.
The role of computer-aided digital microscopy in reducing observer variability in immunohistochemistry is promising.
在数字显微镜中，观察者的变异性以及计算机辅助数字显微镜的影响是研究不足的领域，需要进一步研究，因为数字成像在病理学中的应用越来越多，未来的作用也越来越大。使用计算机辅助可以减少观察者的变异性，从而提高旨在确定新生物标志物效用的研究的统计效力，并加速其在临床实践中的应用。
定量研究数字显微镜和计算机辅助数字显微镜在 HER2/neu 免疫组化分析中的观察者间和观察者内变异性，并检验以下假设：使用计算机辅助显微镜可提高 HER2/neu 免疫组化表达定量评估的观察者一致性。
从 64 张 HER2 抗体染色的乳腺癌组织切片中提取了 335 张数字显微镜图像，由 14 位观察者在 2 种阅读模式下进行阅读：非辅助模式和计算机辅助模式。在非辅助模式下，HER2 图像显示在经过校准的彩色显示器上，没有其他信息；而在计算机辅助模式下，观察者会看到一个 HER2 图像，同时还会显示一个特征图，该特征图显示了正在检查的特定图像的膜染色强度和膜完整性的计算机提取值，同时还显示了不同 HER2 类别的平均特征值。在这两种模式下，观察者都被要求提供 HER2 表达的连续评分。
对研究结果进行的一致性分析表明，当使用计算机辅助阅读模式评估预选图像区域时，观察者间和观察者内的一致性都有显著提高。
计算机辅助数字显微镜在减少免疫组化中观察者变异性方面具有广阔的前景。
