Application of high-frequency ultrasound in occult focal liver lesions: Does it help?

ObjectivesTo investigate the role of high-frequency ultrasound in detection of occult focal liver lesions (FLLs).MethodsIn this retrospective study from April 2016 to March 2019, eighty-five patients with indistinctive FLLs were included. High-frequency and low-frequency B-mode ultrasound (BMUS) and contrast-enhanced ultrasound (CEUS) were performed for each lesion. The detection rates of two methods and the ultrasound performance of co-detected lesions were compared. Subgroup analysis was performed according to different liver backgrounds.ResultsFor 85 FLLs with mean diameter of 11.80 ± 4.66 mm and mean depth of 20.91 ± 6.89 mm, high-frequency BMUS detected 77 (90.6%) lesions, significantly more than low-frequency BMUS (36, 42.4%, p < 0.001). Among the lesions co-detected by low-frequency and high-frequency ultrasound, the lesions at high-frequency mainly showed heterogeneous echogenicity (p < 0.001), regular morphology (p < 0.001), well-defined boundary (p < 0.001) and inhomogeneous enhancement (p < 0.001) in arterial phase. Even in the presence of cirrhosis or fatty liver, high-frequency ultrasound still performed excellently.ConclusionHigh-frequency ultrasound improves the detection of small and superficially located FLLs.