This large case series of 35 children indicates that Magnetic Resonance Elastography (MRE) may be quite useful to assess hepatic fibrosis as well as steatosis (J Pediatr 2014; 164: 186-8).
The study (2011-2012) included 27 patients with nonalcoholic fatty liver disease (NAFLD); 22 of this group had probable or definite nonalcoholic steatohepatitis (NASH). Other diseases included progressive familial intrahepatic cholestasis (type 2), autoimmune sclerosing hepatitis, Wilson disease, glycogenic hepatopathy (due to type 1 diabetes), and other liver conditions. All of the patients in the study had undergone liver biopsy as well.
The authors showed that MRE had a high accuracy to detect significant fibrosis and may be better suited for severely obese patients. At the cutoff they identified, the sensitivity was 88% and the specificity 85% for detecting significant fibrosis.
In severely obese patients, alternative imaging techniques, namely transient elastography and acoustic radiation force imaging have higher technical failure rates. The authors note that at their institution, more than 100 MRE studies have been completed (including many without liver biopsies); thus far, only two morbidly obese patients failed completion. In addition, the authors state that this limited study costs about twice that of an ultrasound.