QUANTITATIVE MYOCARDIAL MAPPING OF PERFUSION AND METABOLISM USING PARAMETRIC POLAR MAP DISPLAYS IN CARDIAC PET

Most efficacy studies of cardiac PET in demonstrating myocardial ische mia and viability have been performed using one or more transversal st atic images of the heart. In contrast, in this paper we describe a met hod of functional imaging of the complete left ventricular myocardium for perfusion with nitrogen-13-ammonia, both at rest and during a dipy ridamol stress test, and of glucose metabolism with F-18-fluorodeoxygl ucose ((18)FDG). Methods: This was performed by using the data of each of 48 radial segments of 10 short-axis images as tissue data and LV c avity data of three basal planes as blood pool data. The study describ es the results of 19 normal volunteers and 36 patients with coronary a rtery disease. From the data of the normal volunteers a 95% normal con fidence interval was calculated for each imaging modality. These inter vals were then used to describe the patient data as normal, ischemic o r infarcted. Results: The results of analysis of the parametric images was compared with the results of static analysis of the same patient data and found to be less dependant on the detection threshold used. C onclusion: The described method enables the routine application of fun ctional PET imaging of the total myocardium by the semi-automatic cons truction of parametric flow and metabolism polar maps. It thus provide s an increased performance in the diagnosis, quantification and locali zation of myocardial ischemia and viability over conventional PET imag ing.