The purpose of this study is to investigate clinical feasibility of annual non-contrast magnetic resonance imaging for surveillance of hepatocellular carcinoma in high-risk group, in comparison with biannual ultrasonography.

The purpose of this study is to investigate clinical feasibility of annual non-contrast magnetic resonance imaging for surveillance of hepatocellular carcinoma in high-risk group, in comparison with biannual ultrasonography. In addition, the relationship between non-contrast MR parameters and clinical manifestation of liver function is investigated.

Inclusion Criteria:

• equal to or older than 40 years
• under surveillance using biannual ultrasonography (USG) and presence of liver USG within 6 months (+/- 1month)
• risk index is equal to or higher than 2.33 (Risk Index = 1.65 (if the prothrombin activity is <=75%) + 1.41 (if the age is 50 years or older) + 0.92 (if the platelet count is <=100x10(3)/mm3) + 0.74 (if the presence of HCV or HBsAg is positive)).
• signed informed consent

Exclusion Criteria:

• under 40 years
• history of HCC
• patients with pregnancy or nursing
• any contraindication of MRI
• any contraindication of CT