The purpose of this study was to assess the value of high-frame-rate contrast-enhanced ultrasound (H-CEUS) in the diagnosis of small (≤3 cm) focal liver lesions in patients with chronic liver disease.

From January 2018 to April 2023, 153 patients with chronic liver disease (176 lesions, ≤3 cm) who underwent CEUS and H-CEUS examinations at Ruijin Hospital and its Wuxi Branch were retrospectively analyzed. CEUS and H-CEUS images were interpreted independently by two doctors and image features were statistically analyzed between CEUS and H-CEUS. The χ² test was used to compare the differences in the characteristics of the two contrast-enhanced models (start enhancement time, enhancement degree, uniformity, fill-in direction, and vascular morphology) between the benign and malignant groups. The diagnostic performance of the two modalities was assessed by calculating sensitivity, specificity, accuracy, etc.

The start time, intensity, and homogeneity of enhancement did not differ significantly between CEUS and H-CEUS (P>0.05). Fill-in direction and vascular morphology differed significantly between CEUS and H-CEUS (χ²=6.480 and 58.284, P=0.011 and P<0.001, respectively) in the malignant group. H-CEUS had a higher sensitivity (93.68% vs 80.00%) and accuracy (92.61% vs 83.52%) than CEUS in the differential diagnosis of small focal liver lesions (χ²=7.784 and 6.921, P=0.005 and 0.009, respectively), but there was no statistical difference in specificity between the two modalities (P>0.05).

By increasing the frame rate of real-time images, H-CEUS can dynamically and accurately display fill-in patterns and vascular morphology in the arterial phase, thereby improving the differential diagnosis of small focal liver lesions.