Myocardial blood flow from SPECT

Excerpt

Quantification of myocardial blood flow (MBF) at stress and rest in ml/g/min and determination of the myocardial flow reserve (MFR) have long been the domain of PET myocardial perfusion imaging (MPI) with tracers such as ¹⁵O-Water, ¹³NH₃-Ammonia, and more recently ⁸²Rubidium. Although at this time, in the routine clinic, PET are currently primarily analyzed visually or at most, semi-quantitatively for the presence and severity of relative perfusion defects using static perfusion images, the MFR measurements can be readily obtained, by re-reconstructing the list mode data. This is in particular true for the new 3D PET/CT systems. Thus, the additional quantitative flow measurements can be obtained without additional imaging time or radiation exposure during PET MPI, and therefore are becoming incorporated in the clinical practice. The additional prognostic value of MFR measurements over standard measurement of ischemia has been conclusively demonstrated in two large studies.1,2 The potential added diagnostic value of flow measurements for improved prediction of obstructive coronary disease has also been suggested.3,4 …