SCINTIGRAPHIC DIAGNOSIS OF CORONARY-ARTERY DISEASE - MYOCARDIAL BULLS-EYE IMAGES CONTAIN THE IMPORTANT INFORMATION

The bull's-eye image, also called polar map image, has been developed as an important display for the visual and quantitative analysis of my ocardial perfusion scintigrams. Quantitative analysis can be performed for example by comparing areas in the bull's-eye image with normal li mits or by processing it using artificial neural networks. The usefuln ess of such methods is highly dependent on the information content of the bull's-eye image. The purpose of this study was to investigate whe ther there is more diagnostically important information in a set consi sting of the myocardial bull's-eye image plus tomographic slice image than in the bull's-eye image alone. A population of 135 patients who h ad undergone both myocardial scintigraphy and coronary angiography, wi th no more than 3 months elapsing between the two examinations, was st udied retrospectively. Four experienced observers independently classi fied visually all scintigrams regarding the presence/absence of corona ry artery disease in two vascular territories using a few-grade scale. The observers classified the scintigrams once viewing bull's-eye imag es only, and once viewing tomographic slices and bull's-eye images. Co ronary angiography was used as gold standard. The classifications were evaluated using the areas under the receiver operating characteristic s (ROC) curves. The classifications based on bull's-eye images only we re slightly more accurate than those based on tomographic slices and b ull's-eye images in one of the two vascular territories (ROC areas of 0.66 vs. 0.64). The opposite relationship was found in the other vascu lar territory (0.78 vs. 0.81). None of the differences was statistical ly significant. In conclusion, the diagnostically important informatio n fur the diagnosis of coronary artery disease by myocardial perfusion scintigraphy is present in the bull's-eye image.