Measurement of liver fat content using selective saturation at 3.0 T

Purpose: To validate an MRI technique for measuring liver fat content by calibrating MRI readings with liver phantoms and comparing MRI measurements in human subjects with estimates of liver fat content on liver biopsy specimens. Materials and Methods: The MRI protocol consisted of fat and water imaging by selective saturation using a 3.0-T scanner. A water phantom and liver phantoms were scanned before each of 10 human subjects who under-went a liver biopsy to assess for nonalcoholic fatty liver disease (NAFLD). Liver fat content in human subjects was derived from a calibration curve generated by scanning the phantoms. Liver fat was also estimated by optical image analysis and pathologists' assessment of histologic sections. Results: MRI measurements of the liver phantoms were highly reproducible. Measurements of liver fat content in human subjects made by MRI in two areas of the liver were strongly correlated (r = 0.98, P < 0.001). MRI measurements were highly associated with estimates of liver fat content made by optical image analysis (r = 0.96, P < 0.001) and with estimates made by the pathologists (r 0.93, P < 0.001). Conclusion: We validated a technique for quantifying liver fat content based on selective fat and water imaging. The technique is accurate and reproducible and provides a noninvasive method to obtain serial measurements of liver fat content in human subjects.