Liver biopsy and histologic grade

Basically, ultrasonography-guided liver biopsy was performed using an 18-gauge core biopsy needle (TSK Stericut Standard type with Co-axial; TSK) with a free-hand technique under sedation supervised by anesthesiologists in patient with infantile cholestasis. However, if BA or choledochal cyst was strongly suspected, liver biopsy was performed during operation.

All specimens were evaluated for histopathologic diagnosis of cholestasis and grading hepatic fibrosis by hepatobiliary pathologists. The fibrosis grades of pathologic specimens of all cases were evaluated by METAVIR fibrosis grade, ranging from grade F0 to F4 (F0, no fibrosis; F1, portal fibrosis without septa; F2, portal fibrosis with few septa; F3, numerous septa without cirrhosis; and F4, cirrhosis). Clinically significant fibrosis was defined as grade F2 to F4 and advanced fibrosis was defined as grade F3 to F4[15,16].