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Effect of iterations and time of flight on normal distributions of 82Rb PET relative perfusion and myocardial blood flow

Journal of Nuclear Cardiology Aims and scope



As clinical use of myocardial blood flow (MBF) increases, dynamic series are becoming part of the typical workflow. The methods and parameters used to reconstruct these series require investigation to ensure accurate quantification.


Fifty-nine rest/stress dynamic 82Rb PET studies, acquired on a Biograph mCT, from a combination of normal volunteers and low-likelihood patients were reconstructed with and without time of flight (TOF) for varying iterations and processed to obtain relative perfusion and MBF polar maps. Regional values from mean polar maps were fit to a linear mixed-effect model to quantify convergence and select the optimal number of iterations.


TOF reconstructions converged faster and yielded more uniform relative perfusion polar maps. However, the stress MBF distribution for TOF reconstructions was more heterogeneous, with a higher-intensity septal wall. This phenomenon requires further investigation, with right ventricle blood pool spillover possibly having an effect. Optimal reconstructions were defined as 5-iteration non-TOF (24-subset) reconstructions and 3-iteration TOF (21-subset) reconstructions.


Optimal cardiac reconstructions were identified for non-TOF and TOF reconstructions of dynamic series. TOF reconstruction presents as the more accurate method, given the more uniform relative perfusion distribution.

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Positron emission tomography


Computed tomography


Time of flight




Myocardial blood flow


Myocardial flow reserve


Left ventricle


Right ventricle


Blood pool


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A. Poitrasson-Rivière, J.B. Moody, T. Hagio, and J.M. Renaud are employees of INVIA. J.M. Renaud is a consultant for Jubilant DraxImage and receives royalties from the sales of FlowQuant® software. L. Arida-Moody has nothing to disclose. V.L. Murthy is supported by R01AG059729 from the National Institute on Aging, U01DK123013 from the National Institute of Diabetes and Digestive and Kidney Disease, and R01HL136685 from the National Heart, Lung, and Blood Institute as well as the Melvyn Rubenfire Professorship in Preventive Cardiology. Dr. Murthy has received research grants and speaking honoraria from Siemens Medical Imaging. He serves as a scientific advisor for Ionetix and owns stock options in the same. Dr. Murthy also owns stock in General Electric and Cardinal Health. He has received expert witness payments on behalf of Jubilant Draximage and a speaking honorarium from 2Quart Medical. Dr. Murthy receives non-financial research support from INVIA Medical Imaging Solutions. E.P. Ficaro is a stockholder of INVIA, which produces Corridor4DM, a clinical software package for nuclear cardiology.

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Correspondence to Alexis Poitrasson-Rivière PhD.

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Poitrasson-Rivière, A., Moody, J.B., Renaud, J.M. et al. Effect of iterations and time of flight on normal distributions of 82Rb PET relative perfusion and myocardial blood flow. J. Nucl. Cardiol. 29, 2612–2623 (2022).

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