抄録
The purpose of this study is to diagnose heart diseases automatically from chest X-ray films.
Cardiac shape is represented by a closed curve which is a seventh-order polynomial least-square-approximation. It is shown that the shape of the entire cardiac shadow can be represented by this model. Although this model originally has six parameters, result of principal component analysis indicates that this model can approximately be expressed (up to 98.5% in variance) by only three main components.
By reproducing cardiac shapes using three main components and diagnosing for heart diseases, the distribution of diseases is plotted in a three-dimensional space. If one is to diagnose heart disease from this distribution diagram, classification is correct for 70.0% of typical 23 cases.
Parameters used in this model can be extracted by sequentially fitting the model to an actual X-ray film. Noises such as those of the ribs and gas in stomach are eliminated in this procedure, though there are errors of 5% to 10% for three main components.
