Parametric images of myocardial viability using a single [O]H2O PET/CT scan

Perfusable tissue index (PTI) is a marker of myocardial viability and requires acquisition of transmission, [O]CO and [O]H2O scans. The aim of this study was to generate parametric PTI images from a [O]H2O PET/CT scan without an additional [O]CO scan. Methods: Data from 20 patients undergoing both [O]H2O and [ O]CO scans were used, assessing correlation between PTI based on [O]CO (PTICO) and on fitted blood volume fractions (PTIVb). In addition, parametric PTIVb images of 10 patients undergoing [O]-H2O PET/CT scans were generated using basis-function methods and compared with PTIVb obtained using nonlinear regression. Simulations were performed to study the effects of noise on PTIVb. Results: Correlation between PTICO and PTIVb was high (r =0.73). Parametric PTIVb correlated well with PTIVb obtained using non-linear regression (r=0.91). Simulations showed low sensitivity to noise (coefficient of variation < 10% at 20% noise). Conclusion: Parametric PTI images can be generated from a single [O] H2O PET/CT scan.