Low concentration isotonic iodixanol on hepatic and portal veins imaging quality and renal function: A 320-detector...

The effects of different concentrations of isotonic contrast agents on the quality of hepatic and portal vein imaging and their impact on patients' renal function remain unclear. This study aimed to assess whether lower concentrations of iodixanol yield high-quality imaging by comparing hepatic and portal vein imaging quality and evaluating renal function following dual-energy CT (DECT) scans.

Patients were randomly assigned to receive either iodixanol at 270 mgI/mL (iodixanol 270 group, n = 50) or 320 mgI/mL (iodixanol 320 group, n = 50) and underwent DECT with energy-spectrum reconstruction. Quantitative and qualitative image quality parameters, as well as changes in renal function before and after scanning, were compared between the 2 groups.

Significant differences were observed in the contrast-to-noise ratio, signal-to-noise ratio of the main portal vein, and the computed tomography value of the hepatic vein between the 2 groups (P < .05). These parameters were superior in the iodixanol 320 group compared to the iodixanol 270 group. Qualitative evaluation scores for the portal and hepatic veins in the iodixanol 320 group were significantly higher than those in the iodixanol 270 group (P < .05). Postcontrast acute kidney injury incidence was higher in the iodixanol 320 group than in the iodixanol 270 group (20.5% vs 2.1%, P < .05), and this association remained significant after multivariable adjustment (adjusted odds ratio = 13.70, P = .002).

With a fixed injection protocol, iodixanol 320 mgI/mL yielded higher venous enhancement, whereas iodixanol 270 mgI/mL provided diagnostically acceptable portal/hepatic venous image quality on DECT with a lower iodine load. After adjustment, 320 mgI/mL was associated with higher odds of postcontrast acute kidney injury; this safety signal requires confirmation in larger iodine-matched studies.