(A) A map of the average ¹⁸F-NaF uptake made within 1.4 ± 0.6 cm² ROIs in ascending aorta across all patients. Bottom is the aortic valve area, top is the aorta at the innominate artery branch, middle represent outer curvature, and left and right border are the inner curvature. Black areas represent regions with contamination from adjacent structures (e.g. aortic valve, bone), which were excluded from analysis. Regions with highest ¹⁸F-NaF uptake values are mainly located in the inner curvature of the proximal and distal ascending aorta. (B) Bar graph of the regional ¹⁸F-NaF uptake within the aorta *P < 0.05 comparing inner curvature vs. outer curvature, †P < 0.05 compared with aortic root, #P < 0.05 compared to proximal ascending aorta. A, anterior; AoV, aortic valve; AoArch, aortic arch; I, inner; O, outer; P, posterior.