Ultrasound-derived fat fraction for diagnosing hepatic steatosis: a systematic review and meta-analysis.

Objective: To perform a systematic review and meta-analysis to evaluate the diagnostic performance of Ultrasound-Derived Fat Fraction (UDFF) in detecting hepatic steatosis using Magnetic Resonance Imaging-Proton Density Fat Fraction (MRI-PDFF) as the reference standard.

Materials And Methods: Relevant databases were searched through November 2024. Studies that evaluated the UDFF to detect hepatic steatosis using MRI-PDFF as the reference standard met the inclusion criteria. Our primary outcome was the sensitivity and specificity of UDFF compared to MRI-PDFF in distinguishing steatosis from non-steatosis. Analyses were performed using a bivariate random-effects approach, and heterogeneity was considered substantial if I > 50%. A sensitivity analysis was performed to detect potential studies that contribute to heterogeneity.

Results: Nine studies comprising 1150 patients (mean age range, 14-62 years; 51.2% women) were included. Eight studies were performed using the same vendor platform. The pooled sensitivity of UDFF for detecting hepatic steatosis was 90.4% (95% CI: 84.0%, 94.4%), and the pooled specificity was 83.8% (95% CI: 75.1%, 89.8%). The AUC for the summary receiver-operating characteristic curve was 0.93 (95% CI: 0.83, 0.95). Heterogeneity among the studies was low (I² = 22.2%).

Conclusion: UDFF demonstrates high sensitivity and specificity for detecting hepatic steatosis, supporting its value as a noninvasive tool for screening.

Key Points: Question Small individual studies suggest that US-Derived Fat Fraction (UDFF) may effectively detect hepatic steatosis compared to MRI, but no meta-analysis has been performed. Findings In nine studies including 1150 patients, UDFF demonstrated high pooled sensitivity (90.4%) and specificity (83.8%) relative to MRI with low between-study heterogeneity. Clinical relevance UDFF demonstrates high diagnostic accuracy compared with MRI, supporting its use as a noninvasive tool with potentially lower cost and wider availability for large-scale screening of hepatic steatosis.