Previous studies on hepatic multiphase CT using 64-channel MDCT in patients with chronic liver disease recommended an iodine dose of 560-600 mgI/kg or higher. Reducing iodine concentration is expected to minimize the impact on kidney function due to decreases in osmolality and viscosity. Recent advancements in hybrid iterative reconstruction with 128 channels or higher suggest that reducing the amount of iodine used in hepatic multiphase CT may be possible. However, most studies have focused on reducing the amount of iodine contrast while maintaining the same iodine concentration.

Therefore, this study aimed to evaluate whether the image quality and lesion detectability in hepatic multiphase CT using low-concentration iodine contrast (LCIC CT, 270 mg Iodine/mL) are non-inferior to those using high-concentration iodine contrast (HCIC CT, 350 mg Iodine/mL) in patients with chronic liver disease, utilizing 128-channel or higher MDCT and hybrid iterative reconstruction. Additionally, the study sought to determine the cut-off for the amount of iodine per kg that demonstrates acceptable image quality during the arterial phase.