Feasibility of Ultrasound Attenuation Imaging for Assessing Pediatric Hepatic Steatosis

SIMPLE SUMMARY: Hepatic steatosis is associated with cardiovascular disease, diabetes mellitus, and liver cirrhosis. The increasing prevalence of hepatic steatosis among children has become a public health concern. Although liver biopsy is the gold standard for the diagnosis of hepatic steatosis, it has limited value because of invasiveness. Among imaging studies, ultrasonography is readily accessible and can be used to exclude other pathology, but its accuracy is limited by low sensitivity and specificity. Although magnetic resonance imaging is highly accurate for liver steatosis and fibrosis, its application is curbed in children as it requires sedation and longer scan time. Recently, attenuation imaging (ATI) has emerged as a new modality for quantifying fat deposition in the liver in real time. However, investigations of ATI for pediatric hepatic steatosis are still in their preliminary stages. Thus, we investigated the feasibility of ultrasound attenuation imaging (ATI) for assessing pediatric hepatic steatosis. This study demonstrated that ATI can differentiate fatty liver from normal liver as well as moderate to severe fatty liver from mild fatty liver. Thus, ATI may be useful for identifying children who require liver biopsy and early treatment. ABSTRACT: We investigated the feasibility of ultrasound attenuation imaging (ATI) for assessing pediatric hepatic steatosis. A total of 111 children and adolescents who underwent liver ultrasonography with ATI for suspected hepatic steatosis were included. Participants were classified into the normal, mild, or moderate–severe fatty liver group according to grayscale US findings. Associations between clinical factors, magnetic resonance imaging proton density fat fraction, steatosis stage and ATI values were evaluated. To determine the cutoff values of ATI for staging hepatic steatosis, areas under the curve (AUCs) were analyzed. Factors that could cause measurement failure with ATI were assessed. Of 111 participants, 88 had successful measurement results. Median ATI values were significantly increased according to steatosis stage (p < 0.001). Body mass index (BMI) was a significant factor for increased ATI values (p = 0.047). To differentiate fatty liver from normal liver, a cutoff value of 0.59 dB/cm/MHz could be used with an AUC value of 0.853. To differentiate moderate to severe fatty liver from mild fatty liver, a cutoff value of 0.69 dB/cm/MHz could be used with an AUC value up to 0.91. ATI can be used in children as an effective ultrasonography technique for quantifying and staging pediatric hepatic steatosis.