CT calcification patterns of peripheral arteries in patients without known peripheral arterial disease

Purpose: In the last few years histologic studies of peripheral arteries have shown that both intimal and medial calcifications are found in patients in an early, asymptomatic stage and that differentiation between medial and intimal calcifications is possible. The aim of this study was to assess the computed tomography (CT) calcification characteristics in peripheral arteries and to explore potential patterns in subjects without peripheral arterial disease (PAD). Method: Retrospectively, 204 patients without known PAD were studied. The thin slice CT-imaging characteristics severity, annularity, thickness and continuity were scored in the following arteries: plantar and dorsal, crural, femoro-popliteal, iliac and the abdominal aorta. Interrelation was assessed using linear regression and significance was tested by Chi-Square tests. Results: In the crural arteries two calcification patterns with strong associations were found. Pattern 1: continuous-annular 93.5 % (29/31), continuous-thin and thin-annular both 73 % (27/37, p < 0.001) and pattern 2: thick-discontinuous 91.7 % (44/48), thick-dotted 68.8 % (33/48), patchy-dotted 59.3 % (16/27, p < 0.001). Similar associations were found in the femoro-popliteal artery, but not in the plantar, dorsal, iliac arteries and aorta. Conclusions: In the crural and femoropopliteal arteries at least two morphological patterns can be distinguished on CT that, compared to a CT-histologically validated score, may represent an intimal and medial calcification pattern.