OBJECTIVE: To detect the feasibility and theoretic basis for treatment with hyperbaric oxygenation (HBO) in chronic hepatitis and to compare the changes in hepatic function, immunity, pathologic morphology, ultrastructure and HBV in hepatic tissues before and after treatment. METHODS: Sixty cases of chronic hepatitis were randomly selected and divided into two groups: the experiment (n = 30) and control groups (n = 30). Patients in the experimental group were treated with HBO for 6 courses. Patients in the control group were treated for 60 days with the usual drugs used in the clinic. The function and bloodstream graph of liver were examined and liver biopsies were made before and after treatments. Routine paraffin sections were stained with HE and observed under the light microscope. Ultra thin slides from paraformaldehyde and glutaraldehyde fixed liver tissue were stained with lead citrate and observed with the transmission electric microscope. HBsAg and HBcAg in liver of the experimental group were detected with ABC immunohistochemistry method before and after treatment. RESULTS: For the experimental group, ALT, SB, gamma-GT, AKP, IgG, and IgM in blood and the degeneration and necrosis of hepatocytes were remarkably decreased (P 0.05), and the expression of HBsAg and HBcAg in liver was not weakened (P
