The objective of this study is: (1) to investigate the correlation of ultrasound parameters (SW speed, Dispersion slope, Attenuation value, Normalized Local Variance, Liver / Kidney Intensity Ratio) with the pathological parameters (fibrosis, intralobular inflammation, ballooning degeneration and steatosis); (2) to evaluate the diagnostic performance of SW speed for liver fibrosis, Dispersion slope for intralobular inflammation and Attenuation value for steatosis by comparison with the tissue diagnosis by liver biopsy.

Inclusion Criteria:

• Nonalcoholic fatty liver disease (NAFLD) patients who are scheduled for liver biopsy for the differential diagnosis of NASH and/or NAFLD patients who are scheduled for the MR elastography (MRE) and MRI-proton density fat friction (MRI-PDFF).
• Without a history of alcohol use, which lead to alcoholic hepatic involvement (pure alcohol below 30 g/day for male, 20 g/day for female).

Exclusion Criteria:

• Patients with endocrine disorder (hypopituitarism, growth hormone deficiency, hyperthyroidism etc.), serious nutrition disorder, and drug-induced hepatic involvement (steroid, tamoxifen, valproic acid, amiodarone etc.), which may lead to the steatosis
• Hepatitis B, Hepatitis C and HIV patients
• Primary biliary cholangitis, Primary sclerosing cholangitis, and Autoimmune hepatitis patients
• Wilson's disease, α1-antitrypsin deficiency, and hemochromatosis patients
• Malignant liver tumor, common bile duct stone, and jaundice patients
• Patients after jejunoileal bypass surgery or massive intestinal resection surgery
• Patients whose treatment changes during the period between imaging examination and liver biopsy, including medications such as antidiabetic drugs and other treatments which may change the fat deposition or inflammation of liver.

Nonalcoholic fatty liver disease (NAFLD) patients who are scheduled for liver biopsy for the differential diagnosis of NASH and/or NAFLD patients who are scheduled for the MR elastography (MRE) and MRI-proton density fat friction (MRI-PDFF).