The aortoiliac bifurcations were divided into three regions based on the area changes: an apical region corresponding to the bifurcation apex (taper = 2.96 ± 0.80 mm²/mm), a preapical region (flare = 3.58 ± 0.87 mm²/mm), and the postapical region (flare = 0.82 ± 0.80 mm²/mm).
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