Abstract: ObjectiveTo explore the possibility of optimizing liver MRI enhancement scanning process， the changes of T2WI signal of hepatic parenchyma and intrahepatic common malignancy were studied before and after using contrast agent gadolinium diethylenetriamine pentaacid(GdDTPA.) MethodsEightynine cases were collected normally in the control group and 42 cases which were clinically diagnosed as intrahepatic common malignancy (19 cases of liver cancer and 23 cases of liver metastases)， the changes of T2WI signal were measured and analyzed comparatively. ResultsContrast agent GdDTPA was used to scan normal liver， liver cancer and liver metastases， T2WI signal reduced slightly. The difference was statistically significant (P<0.01). The difference of T2WI signal before enhancement and after enhancement were compared  among groups of normal liver and liver cancer and liver metastases， there were statistically significant difference (P<0.05). However， there was no significant difference on the percentage of signal reduction (P>0.05). By comparing the signal difference before and after enhancement，T2WI signal difference between common malignant lesions in liver and its surrounding normal liver parenchyma was not significantly different (P>0.05). ConclusionHepatic parenchyma and intrahepatic common malignancy were affected by contrast agent， the enhanced degree of T2WI signal was decreased after the enhancement， but it had little effect on the detection of common malignant lesions in liver. Therefore， it is feasible to perform T2WI after enhancement.

Key words: liver neoplasms, magnetic resonance imaging