Pancreatic fat quantification by fat-water MRI provides new insights for analyzing non-alcoholic fatty pancreas disease.

Background: Fatty replacement of the pancreas is a frequent pathological finding reported to correlate with age, obesity and diabetes. Recently, some authors state the concept of non-alcoholic fatty pancreas disease (NAFPD) and show the correlation between non-alcoholic fatty liver disease (NAFLD) and fatty pancreas. For hepatic fat quantification, fat-water magnetic resonance imaging (MRI) which can compute the fatty rate called fat fraction (FF) is commonly used. However, adequate measurement-method for pancreatic FF has not been established because fat replacement of the pancreas is distributed unevenly.Aim: To evaluate the adequacy of our measurement-method of pancreatic FF.Method: Using fat-water MRI images from 152 patients with NAFLD, we measured FF from the whole area of the pancreas appeared in every slice, and calculated the average of FFs from all the voxels. Then, we analyzed the correlations between pancreatic FF and clinical features.Results: As expected, pancreatic FFs statistically correlated with age and obesity as well as diabetes. Interestingly, when pancreatic head-FFs and body-FFs were analyzed separately, age was correlated with only body-FFs, whereas obesity and diabetes were correlated with only head-FFs. Conclusion: Our measurement-method of pancreatic FF was thought to be adequate. This method will provide new insights for analyzing chronic pancreatitis possibly caused by fat accumulation.