DSA protocol

A DSA instrument (INNOVA 3100; GE Healthcare, Chicago, IL, USA) was used. A right transfemoral approach was used for artery access. Initially, the 2 pelvic common iliac arteries were visualised by performing digital angiography in the abdominal aorta (injection volume, 20 ml; injection rate, 15 ml/sec). Subsequently, the two IIAs were catheterised for imaging. The contralateral (usually the left) IIA was initially catheterised and visualised by performing digital angiography in the artery origin in the neutral position and repeating in the contralateral oblique and ipsilateral oblique positions (injection volume, 10 ml; injection rate, 5 ml/sec). The right IIA was visualised by the same method following catheterisation.