Automatic Computation of the Cardiothoracic Ratio with Application to Mass Screening

An algorithm for the automatic computation of the cardiothoracic ratio is presented. In experiments using 100 sheets of 14-by 14-in postero-anterior chest radiographs, a tolerable error of ±4 percent was satisfied in 86 percent of all trials. The processing time is about 1 s. The goal of this study is to provide radiologists with practical Instruments for the automated mass screening of heart disease. A minicomputer and a conventional vidicon camera are used in the experimental system.