Hyperoxia accelerates progression of hepatic fibrosis by up-regulation of transforming growth factor-β expression

Table 1 Degree of hepatic fibrosis

Descriptive diagnosis	Definition
No fibrosis	Normal connective tissue
Portal fibrosis	Fibrous portal expansion
Periportal fibrosis	Periportal fibrosis with short septa extending into lobules or rare porto-portal septa (intact architecture)
Septal fibrosis	Fibrous septa reaching adjacent portal tracts and terminal hepatic venules (architectural distortion, but no obvious cirrhosis)
Cirrhosis	Diffuse nodular formation