For the study, the researchers reviewed 26 patients with NAFLD who underwent CCE MRI. Using a five-point scale, the researchers found that the staging of the NAFLD on CCE MRI closely matched the staging of NAFLD using conventional pathology.
According to the researchers, the prevalence of NAFLD is increasing in western nations and is a major health problem affecting both children and adults. It is a common cause of cirrhosis in American adults and the most common cause in children.
The definitive method of diagnosis and staging is liver biopsy, but it has several limitations, say the researchers. It is invasive, costly, has risks and only samples about 1/50,000th of the liver. "This sampling issue is important because the pathological processes that affect the NAFLD liver are not evenly distributed throughout, so that tiny changes in needle placement will result in potentially large changes in biopsy interpretation. Because of these limitations, alternative methods such as CCE MR need to be developed," said Claude Sirlin, MD, lead author of the study.
"Except for CCE MR, all other experimental techniques rely on surrogate or indirect markers of fibrosis. CCE MR attempts to directly visualize fibrosis by using two contrast agents with complementary mechanisms, iron particles to darken the background liver and gadolinium to brighten the fibrosis," said Dr. Sirlin, "Gadolinium alone and iron particles alone are not adequate for visualization of fibrosis, unless the fibrosis is extremely advanced. However, when given together, the agents show fibrosis with high clarity," he added.