# FI-CEUS: a solution to improve the diagnostic accuracy in MRI LI-RADS-indeterminate (LR-3/4) FLLs at risk for HCC

## TL;DR

This study shows that fusion imaging contrast-enhanced ultrasound improves diagnostic accuracy for liver lesions that are hard to classify with MRI in patients at risk for liver cancer.

## Contribution

FI-CEUS is shown to be more effective than CE-MRI for diagnosing small, MRI-indeterminate liver lesions in HCC-risk patients.

## Key findings

- FI-CEUS had higher diagnostic efficacy than CE-MRI for MRI LI-RADS-indeterminate FLLs.
- FI-CEUS detected more arterial phase hyperenhancement and washout in malignant lesions compared to CE-MRI.
- FI-CEUS is particularly valuable for small (<2 cm) FLLs undetected by conventional ultrasound.

## Abstract

To evaluate the diagnostic accuracy of fusion imaging contrast-enhanced ultrasound (FI-CEUS) of magnetic resonance imaging (MRI) LI-RADS-indeterminate (LR-3/4) and conventional ultrasound undetected focal liver lesions (FLLs) in patients at risk for hepatocellular carcinoma (HCC).

Between February 2020 and July 2021, 71 FLLs in 63 patients were registered for diagnostic performance evaluation respectively for ultrasound-guided thermal ablation evaluation in this retrospective study. Diagnostic performance regarding FLLs was compared between FI-CEUS and contrast-enhanced MRI (CE-MRI).

For diagnostic performance evaluation, among 71 lesions in 63 patients, the diagnostic efficacy of FI-CEUS with LI-RADS was significantly higher than that of CE-MRI (P < 0.05) in both overall and hierarchical comparison (except for the group with lesion diameter ≥2 cm). For malignant lesions, the proportion of arterial phase hyperenhancement (APHE) and washout on FI-CEUS was higher than that on CE-MRI (P < 0.05).

FI-CEUS has a high value in the precise qualitative diagnosis of small FLLs (<2 cm) of MRI LI-RADS-indeterminate diagnosis (LR-3/4) that are undetected by conventional ultrasound in patients at risk for HCC and can be a good supplementary CE-MRI diagnostic method for thermal ablation evaluation.