Abstract
BACKGROUND: Ultrasound (US) is the most commonly used imaging method for guiding percutaneous liver biopsies. For lesions that are invisible on B-mode ultrasound (BMUS), contrast-enhanced ultrasound (CEUS) improves the contrast between neoplasms and liver parenchyma, while emerging fusion imaging techniques can enhance the localization of lesions. Therefore, our study aimed to assess the value of CEUS fusion imaging in detecting and guiding percutaneous liver biopsy for lesions invisible on BMUS. METHODS: Patients with focal liver lesions (FLLs) identified on computed tomography (CT) or magnetic resonance imaging (MRI) but not visible on BMUS were retrospectively included at Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University from September 2019 to December 2023. All patients underwent BMUS fusion imaging and CEUS fusion imaging. We evaluated the lesion visibility, detection rate of BMUS fusion, and CEUS fusion before liver biopsy and the rate of technical success and diagnostic success after CEUS fusion-guided biopsy. RESULTS: This study included 70 FLLs from 61 patients. The mean visibility score of the 70 lesions on BMUS was 1.51±0.52. BMUS fusion detected 31 (31/70, 44.3%) lesions, yielding a mean visibility score of 1.81±1.03. CEUS fusion detected 63 (63/70, 90%) lesions, and achieved a mean visibility score of 2.90±0.30, which was significantly higher than that of BMUS fusion. Subgroup analysis corroborated the superiority of CEUS fusion in detecting infiltrative lesions and lesions <2 cm. Finally, CEUS fusion-guided liver biopsy achieved a technical success rate of 98.4% and a diagnostic success rate of 82.0% (50/61). CONCLUSIONS: Compared with conventional BMUS or BMUS fusion imaging, the combination of CEUS and fusion imaging enabled an increase in the detection rate and lesion visibility of BMUS-invisible lesions, particularly for infiltrative masses and small-sized lesions, thereby increasing operators' confidence and success rate during the percutaneous liver biopsy.