Table 2. The ultrasonography diagnosis criteria of hepatic fibrosis in schistosomiasis endemic regions in China.

Grade	Diagnosis criteria
Grade 0	No scarring and absence of fibrosis.
Grade I	Minimal scarring or fibrous expansion in some perisinusoidal or portal areas; an uninterrupted U-shaped echogenic band usually greater than 4 mm in diameter extended from the left portal vein bifurcation branch to the gallbladder bed.
Grade II	Fibrous expansion and scarring in most perisinusoidal and portal/periportal, with occasional portal-to-portal bridging; an echogenic band with a diameter greater than 10 mm surrounding the central part and major branches of the portal vein, extended external surface of the liver that contains blood vessels.
Grade III	Streak-like septal and fibrous bands of portal areas with conspicuous bridging including portal-to-portal and portal-to-central bridging, spreading into portal vein lumina and periphery of the liver.
Grade IV	Advanced scarring or cirrhosis of the liver, usually a liver lobule completely surrounded by scarring.