Systematic review and meta-analysis assesses SWDS diagnostic accuracy for MASLD liver inflammation grading

OBJECTIVE: Shear-wave dispersion slope (SWDS), a viscosity-related ultrasound biomarker, is increasingly used to evaluate hepatic inflammation in metabolic dysfunction-associated steatotic liver disease (MASLD). We aimed to synthesize the diagnostic performance of SWDS for detecting and grading biopsy-proven liver inflammation. METHODS: We performed a systematic review and diagnostic test accuracy meta-analysis of studies using liver biopsy as the reference standard. The primary analysis used a bivariate random-effects model (Hierarchical summary receiver operating characteristic curve, HSROC) to jointly pool sensitivity and specificity, display the summary operating point with confidence and prediction regions, and compute the summary area under the curve (sAUC). Positive and negative likelihood ratios and the diagnostic odds ratio (DOR) were derived from the model-based summaries. Heterogeneity was described by logit-scale between-study variances and HSROC prediction regions, prespecified study-level covariates were assessed with bivariate meta-regression. RESULTS: Seven studies including 1168 patients met inclusion criteria. Summary sensitivity and specificity were 0.75 (95% CI: 0.71-0.79) and 0.87 (95% CI: 0.80-0.92) for grade ≥A1, 0.78 (95% CI: 0.75-0.81) and 0.77 (95% CI: 0.72-0.81) for grade ≥A2, and 0.64 (95% CI: 0.58-0.70) and 0.79 (95% CI: 0.76-0.81) for grade A3. The corresponding sAUCs were 0.886, 0.856, and 0.847. DORs were 20.08 (95% CI: 11.35-35.50), 11.87 (95% CI: 8.72-16.15), and 6.69 (95% CI: 4.95-9.04) for ≥A1, ≥A2, and A3, respectively. Meta-regression analysis identified high-grade fibrosis (F2-F4) as a major contributor to heterogeneity in sensitivity (R²_Se 75.1%, p < 0.001). CONCLUSION: SWDS demonstrates good diagnostic performance for detecting and grading biopsy-proven liver inflammation in MASLD, particularly for ≥A1 and ≥A2 activity. However, its accuracy is influenced by fibrosis burden, especially for severe inflammation, and should be interpreted in this context.