Influence of different time framings, reconstruction algorithms and post‐processing methods on the quantification of myocardial blood flow from ¹³N‐NH₃ PET images

The aim was to investigate to what extent the quantification of myocardial blood flow (MBF) from dynamic 13 N-NH3 PET images is affected by time frame schemes, time-of-flight (ToF), reconstruction algorithms, blood pool volume of interest (VOI) locations and compartment models in patients with suspected chronic coronary syndrome.A standard MBF value was determined from 25 patients' rest/stress 13 N-NH3 PET/CT images reconstructed with ordered subset expectation maximization (OSEM), 5s time frame for the first frames without ToF, subsequently analyzed using a basal VOI and the deGrado compartment model. MBFs calculated using 2s or 10s for the first frames, ToF, block-sequential regularized expectation maximization (BSREM), apical or large VOI, Hutchins or Krivokapich compartment models were compared to MBFstandard in Bland-Altman plots (bias± SD).Good agreement in global rest/stress MBF (ml/min/g) was found when changing the time frame scheme or reconstruction algorithm (MBFstandard vs MBF2s :-0.02±0.06; MBF10s : 0.01±0.07; MBFBSREM :0.01±0.07), while a lower level of agreement was found when altering the other factors (MBFstandard vs MBFToF :-0.07±0.10; MBFapical VOI: -0.27±0.25; MBFlarge VOI: -0.11±0.10; MBFHutchins :-0.08±0.10; MBFKrivokapich :-0.47±0.50).Quantification of MBF from 13 N-NH3 PET images is more affected by choice of compartment models, ToF and blood pool VOIs than by different time frame schemes and reconstruction algorithms. This article is protected by copyright. All rights reserved.