Ioversol 320

All study participants underwent multiphase CT (iCT256 scanner, Philips Healthcare, Amsterdam, Netherlands) scanning immediately after the MRI. All participants were positioned head-first in supine position. After completion of non-contrast scanning 90-100 ml of the contrast agent Ioversol 320 (JIANGSU HENGRUI MEDICINE CO., LTD., Lianyungang, Jiangsu, China) was injected at the rate of 3 ml/s via an anterior elbow vein by an automated injector pump (Spectris Solaris EP, Medrad, Warrendale, PA, USA). The patients were asked to drink a cup of water through a straw immediately before the CT procedure. Covering the view from sternoclavicular joint to Lumbar 1 vertebrae, the arterial phase scanning (optimal for visualization of the tumor) was performed by tracking the aortic peak, followed by the venous (to detect mediastinal lymphadenopathy and distant metastasis) and delayed phase (to determine the benign nature of the stenosis) scanning at 30s and 2 min after the beginning of the arterial phase, respectively. CT scanning parameters were as follows: slice thickness = 5 mm, slice interval = 5 mm, voltage = 120KV, tube current = 300mAs, detector = 128 × 0.625, pitch = 0.993, FOV = 300 mm.

Philips Brilliance iCT Scanner (Royal Dutch Philips Electronics Ltd, Amsterdam, The Netherlands) and GE LightSpeed VCT® (GE Healthcare, Milwaukee, WI, USA) were used for CECT examinations. Non-ionic ICM were intravenously injected by a high-pressure injector (Ulrich Medical® Inc., Ulm, Germany). The injection doses and injection rates of ICM were adopted according to our institutional protocol [16 (link)]. The ICM used included Iodixanol 270 (GE Healthcare, London, UK), Ioversol 320 (Jiangsu Hengrui Medicine Co., Ltd, Jiangsu, China), Iodixanol 320 (Jiangsu Hengrui Medicine Co., Jiangsu, China), Iohexol 350 (Yangtze River Pharmaceutical Co., Ltd, Jiangsu, China), Iopamidol 350 (Bracco, Milan, Italy), Iobitridol 350 (Guerbet, Paris, France), and Iopromide 370 (Bayer Healthcare, Leverkusen, Germany).