Accuracy of Ultrasound-Guided Attenuation Parameter for Diagnosing Hepatic Steatosis

The purpose of this study is to investigate the diagnostic accuracy of a new noninvasive imaging technique, ultrasound-guided attenuation parameter (UGAP), in diagnosing hepatic steatosis. This single-center retrospective study included 81 UGAP studies performed to guide therapy between July 2022 and June 2023 at a large academic medical center. Patients with either liver biopsy or Magnetic resonance-based proton-density fat fraction (MRI-PDFF) within 12 months of US-UGAP imaging, irrespective of order, were included. Patient demographics, body mass index, liver function tests, UGAP values, MRI-PDFF values, and liver biopsy results were obtained from a review of the medical records. Presence of steatosis was defined as PDFF >5.2% or >5% of hepatocytes with steatosis at pathology. Area under the ROC curve (AUROC) was used to measure UGAP accuracy for the detection of hepatic steatosis with statistical significance P < 0.05. There was a significant positive correlation between UGAP and MRI-PDFF (r = 0.463; P < 0.001; confidence interval [CI]: 0.220;0.651). The AUROC to differentiate absence of steatosis (n = 21) from presence of steatosis (n = 32) for UGAP with MRI as the gold standard was 0.760 (P < 0.001; CI: 0.623;0.867). A UGAP value >0.66 had 78% sensitivity and 67% specificity to identify steatosis presence on MRI-PDFF. The AUROC to differentiate absence of steatosis (n = 11) from presence of steatosis (n = 21) for UGAP with pathology as the gold standard was 0.894 (P < 0.001; CI: 0.734;0.974). A UGAP value >0.57 had 100% sensitivity and 64% specificity to identify steatosis presence at pathology. UGAP is an accurate measure for detecting the presence of hepatic steatosis and may be a noninvasive method for metabolic dysfunction-associated steatotic liver disease diagnosis and follow-up.