Liver function estimation using multiphase hepatic CT: diagnostic performance of iodine-uptake and volumetric...

Area of Science:

• Radiology
• Hepatology
• Medical Imaging

Background:

• Multiphase CT is widely used for hepatobiliary diseases but its role in liver function assessment is underexplored.
• Accurate liver function assessment is crucial for surgical planning, especially for major hepatectomy.

Purpose of the Study:

• To evaluate multiphase CT's ability to predict liver function, specifically severe dysfunction (ICG-R15 ≥ 20%).
• To compare CT-derived parameters with ^99mTc-GSA scintigraphy for predicting severe liver dysfunction.

Main Methods:

• Retrospective analysis of 118 patients undergoing multiphase CT, indocyanine-green-retention test (ICG-R15), and ^99mTc-GSA scintigraphy.
• Quantification of CT-derived parameters: extracellular volume fraction (ECV), iodine washout rate (IWR), liver volume (LV/BSA), and spleen volume (SpV/BSA).
• Comparison of CT parameters and ^99mTc-GSA indices (HH15, LHL15) between patients with and without severe liver dysfunction (ICG-R15 ≥ 20%).

Main Results:

• Iodine washout rate (IWR) and ^99mTc-GSA liver receptor index (LHL15) showed the strongest correlation with ICG-R15.
• IWR (AUC=0.845) and LHL15 (AUC=0.878) demonstrated high diagnostic performance for severe liver dysfunction.
• Combined CT parameters (IWR, SpV/BSA, LV/BSA) achieved a high AUC of 0.924 for predicting severe liver dysfunction.

Conclusions:

• Iodine washout rate (IWR) is a superior CT-derived predictor of liver function compared to ECV and volumetry.
• Combining IWR with liver and spleen volumetry on routine hepatic CT provides accurate prediction of severe liver dysfunction.
• CT-based assessment can aid in optimizing treatment strategies and predicting prognosis in patients with liver disease.