18Fluorine-sodium fluoride positron emission tomography to evaluate arterial calcification in patients with chronic kidney disease: a pilot study

¹⁸Fluorine-Sodium Fluoride Positron Emission Tomography (¹⁸F-NaF PET) allows for the detection of arterial micro-calcification, but its data on people with chronic kidney disease (CKD) is limited. This pilot study aimed to determine the optimal time to perform ¹⁸F-NaF PET static scan and to characterize arterial macro- and micro-calcification in CKD. In 7 patients with CKD stages 3b-4 and 3 non-CKD individuals, following the injection of ¹⁸F-NaF, an electrocardiogram-gated chest CT, a 30-min dynamic PET, and three 10-min static PET were acquired. Radiopharmaceutical uptake was quantified for regions including the lumbar spine and 4 aortic segments. Arterial macro-calcification was quantified using Agatston scoring and micro-calcification using tissue-to-background ratio (TBR; reference: right atrium). The standardized uptake value (SUV) in lumbar spine reached a steady state ~ 60 min after injection and was comparable at each time point between CKD and non-CKD (p: 0.58-0.92). Among CKD participants, 6 had macro-calcification in coronary arteries. Abdominal aorta had the greatest macro-calcification, and ascending aorta had the lowest TBR_peak. In the ascending aorta, macro-calcification negatively correlated with TBR_peak (rho = - 0.86, p = 0.01). In descending thoracic aorta, TBR_peak negatively correlated with serum calcium (rho = - 0.81, p = 0.03), and positively correlated with parathyroid hormone (rho = 0.93, p = 0.003) and thrombomodulin (rho = 0.79, p = 0.04). The optimal time for ¹⁸F-NaF PET static scan is ~ 60 min for people with and without CKD. Evaluation of macro- and micro-calcification in aorta revealed preliminary spatial patterns and their associated serum markers. Our findings help to establish technical specifications for image acquisition and analyses of ¹⁸F-NaF PET/CT in CKD.