A method of identifying perfusion abnormalities in a heart of a patient. The method is performed with a patient stress map including stress values, a patient rest map including rest values, and one or more normal maps. The normal maps may include a normal change limit map including change limits, and a normal stress limit map including stress limits. The stress and rest maps are co-registered with one another and the normal maps. The method includes creating a patient change map by subtracting the rest count values of the rest map from the stress count values of the co-registered stress map. Then, in some embodiments, the patient stress and change maps are jointly compared to the normal stress and change limit maps to detect one or more hypoperfused regions. In such embodiments, the one or more regions detected are identified as having perfusion abnormalities and optionally displayed.