Dacre J E, Huskisson E C
Department of Rheumatology, St Bartholomew's Hospital, West Smithfield, London.
Br J Rheumatol. 1989 Dec;28(6):506-10. doi: 10.1093/rheumatology/28.6.506.
We have developed an automatic system for the measurement of joint space in the knee using computerized analysis of digital stored images of knee radiographs. PA X-rays of the knee are positioned on a conventional viewing box. A video image of the radiograph is converted to digital form, stored and displayed on a closed circuit television monitor. This is edited and analysed by a microcomputer. After careful positioning under a computer generated grid on the television screen, automatic measurements are made using an edge detection facility. Two different edge detection algorithms were compared. Reproducibility is very good. Inter- and intra-observer relationships are also good with no significant difference between observers using a paired t-test and very good correlations. Results show that rapid, reliable and accurate measurement of joint space size can be achieved using digital image analysis. The application of image handling computers to radiological scoring is important in our understanding of joint destruction and the progression of the rheumatic diseases.
我们已经开发出一种自动系统，通过对膝关节X光片的数字存储图像进行计算机分析来测量膝关节间隙。膝关节的正位X光片放置在传统的阅片箱上。X光片的视频图像被转换为数字形式，存储并显示在闭路电视监视器上。由微型计算机对其进行编辑和分析。在电视屏幕上计算机生成的网格下仔细定位后，使用边缘检测工具进行自动测量。比较了两种不同的边缘检测算法。重复性非常好。观察者间和观察者内的关系也很好，使用配对t检验时观察者之间无显著差异，且相关性非常好。结果表明，使用数字图像分析可以快速、可靠且准确地测量关节间隙大小。图像处理计算机在放射学评分中的应用对于我们理解关节破坏和风湿性疾病的进展非常重要。
