Ultrasonography and magnetic resonance imaging to measure fatty liver or hepatic steatosis among children was not supported by a recent systematic review.
Researchers analyzed nine previous studies (n=610; birth to 18 years of age), that evaluated the efficacy of measuring hepatic steatosis through noninvasive imaging. Four studies used ultrasound, computed tomography (CT) and five used magnetic resonance imaging (MRI). The investigators searched in PubMed and collected peer-reviewed journals from January 1982 to December 2012 that focused on evaluating imaging models that measured hepatic steatosis and presence of fatty liver.
Researchers did not find a consistent relationship between ultrasound steatosis score and measurement of hepatic steatosis and MRI results varied based on methodologies used. Ultrasonography had positive predictive values of fatty liver between 47% and 62%. Liver fat measurements by MRI were associated with results from histologic analyses, but sample size prevented any diagnostic accuracy assessment. In one study that evaluated 70 children in Cairo, Egypt, liver histology determined 47% of children (15 of 32) with a positive liver ultrasound for steatosis had fatty liver, but the number of children with fatty liver without having a liver biopsy was unknown; therefore the accuracy of ultrasound grading of steatosis could not be determined. In a study from Rome, Italy, 208 children were included and the individual score category determined by researchers did not accurately predict the histologic category. Two other studies used MRIs as the quantitative comparator against which ultrasound findings were evaluated. Results indicated a limited ability to accurately grade the severity of steatosis.
“The available evidence does not support the use of ultrasound for diagnosis or grading of fatty liver in children,” researchers said. “Data suggest that MRI may have better utility, but sufficient, supportive data are lacking. Improvement in the imaging technology for the assessment of liver fat in children and the validation of such technology should be considered an urgent need for patient care and research.”
Disclosure: Researcher Claude Sirlin received a research grant from General Electric.