Objective:

To investigate the ultrasonography and clinicopathology features of intrahepatic bile duct adenoma (BDA).

Methods:

Six patients with BDA diagnosed by biopsy and surgery pathology in Zhongshan Hospital and Xiamen Branch

Fudan University from January 2019 to July 2021 were analyzed for the characteristics of conventional ultrasound and contrast-enhanced ultrasound (CEUS)

and their characteristics were summarized in combination with the clinical and pathological manifestations.

Results:

There were 9 lesions in 6 patients

all of which were located under the liver capsule. The maximum lesion size was 12 mm10 mm and the minimum lesion size was 6 mm5 mm. In 2 of the 9 lesions

hyper echo appeared in the center

surrounded by low echo ring

similar to the target ring sign

which had a certain correlation with pathology. Three lesions were clearly demarcated

and six lesions were poorly or ill-demarcated. There was no obvious color blood flow in Doppler ultrasound. CEUS showed rapid overall enhancement in six lesions and synchronous enhancement in three lesions. All of the 9 lesions showed rapid entry and rapid exit in the late arterial or portal phase. Three benign lesions and six malignant lesions were diagnosed by ultrasonography

and the accuracy was 33.3%. Pathologically

a large number of proliferative bile ducts can be seen in this disease

accompanied by extensive chronic inflammatory cell infiltration

and the bile duct epithelium is well differentiated. With the progressof the disease

the proliferative bile ducts and infiltrating inflammatory cells in the lesion gradually decrease

while the fibrous tissue gradually increases.

Conclusion:

Ultrasonography and clinicopathology of BDA have certain characteristics

and it is helpful to understand BDA and improve the diagnostic accuracy.