Saline-push improves rubidium-82 PET image quality

INTRODUCTION: Rubidium-82 ((82)Rb) PET is used widely for myocardial perfusion imaging. The purpose of this study was to investigate if an additional saline-push following the (82)Rb elution improves PET image quality. METHODS: (82)Rb PET scans were acquired with and without 26 mL saline-push in six patients as part of a clinical quality improvement program. Dynamic images were analyzed to measure the total activity delivered to the superior vena cava (SVC) and retained in the left ventricle (LV) myocardium. Tracer uptake images were used to measure blood background coefficient-of-variation (COV), myocardium-to-blood signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) to assess image quality. RESULTS: Similar eluted activity was measured with/without the saline-push (830 vs 795 MBq; P = 0.24). The activity delivered to the heart and retained in the myocardium was consistently increased more than twofold (SVC: + 114% and LV: + 104%; P < 0.001) with the saline-push. Image quality was improved in all patients, with lower background noise (COV: − 19%), higher SNR (+ 24%) and CNR (+ 27%) (all P ≤ 0.01). CONCLUSIONS: The saline-push used to flush (82)Rb activity out of the infuser tubing, patient injection and intravenous access lines consistently increased the activity delivered to the heart by twofold. This technique is recommended to maximize image quality with (82)Rb PET. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s12350-018-1261-4) contains supplementary material, which is available to authorized users.