AN AUTOMATED-ANALYSIS PROGRAM FOR THE EVALUATION OF CARDIAC PET STUDIES - INITIAL RESULTS IN THE DETECTION AND LOCALIZATION OF CORONARY-ARTERY DISEASE USING NITROGEN-13-AMMONIA

Positron emission tomography (PET), in combination with myocardial blo od flow tracers, allows highly accurate diagnosis of coronary artery d isease using visual data interpretation. To increase the objectivity o f data analysis and to reduce interobserver variability, we developed an automated analysis method for the three-dimensional definition of m yocardial activity, which includes true volumetric data extraction and mathematical constraints of activity sampling to the expected shape o f the left ventricle. Data are displayed in a standardized polar map o r three-dimensional format for comparison with a normal database. The first clinical evaluation of this method in 52 patients using receiver operating characteristics (ROC) curve analysis demonstrated high diag nostic accuracy for detection as well as localization of coronary arte ry stenosis in predefined vascular territories. The interobserver and intraobserver agreement for localization of disease was excellent, wit h correlation coefficients varying from 0.85 to 0.99 for individual va scular territories. Thus, this automated quantitative analysis program provides highly accurate and reproducible evaluation of cardiac PET f low studies. Definite determination of its diagnostic accuracy require s a prospective multicenter trial in a larger patient population emplo ying the criteria for abnormality established in this initial clinical evaluation.