Ultrasound and MRI abdominal fat distribution and its associations with metabolic conditions in adults with abdominal obesity.
Level 4 - case-series / case-control
Cross-sectional diagnostic validation study comparing ultrasound to MRI.
PubMed 41403258 · doi:10.1111/dom.70390
What was done
A cross-sectional study (NCT05882149) evaluated 113 adults (65.5% women, mean age 52.8 ± 10.9 years) with abdominal obesity (waist circumference ≥102 cm for men, ≥88 cm for women). Subcutaneous (SAT) and visceral adipose tissue (VAT) thicknesses were measured using both ultrasound and MRI (gold standard). Diagnostic performance for detecting prediabetes and metabolic syndrome was assessed using ROC curve analysis.
What was found
Ultrasound-measured VAT thickness correlated strongly with MRI (r = 0.82). In women, ultrasound VAT thickness showed fair diagnostic accuracy for prediabetes (AUC = 0.71, cut-off 5.87 cm) and poor accuracy for metabolic syndrome (AUC = 0.69, cut-off 4.83 cm). The ultrasound VAT/SAT thickness ratio in women had fair accuracy for prediabetes (AUC = 0.72, cut-off 3.04) and poor accuracy for metabolic syndrome (AUC = 0.69, cut-off 2.52). Numeric diagnostic performance values for men were not reported in the abstract.
Why it matters
Ultrasound offers an accessible, low-cost surrogate for MRI to quantify visceral fat thickness, though its standalone capacity to discriminate prediabetes and metabolic syndrome remains modest.
Limits
Cross-sectional design limits assessment to correlation rather than longitudinal risk prediction. The sample size was modest (n = 113) and restricted exclusively to individuals with abdominal obesity. Diagnostic accuracy metrics were only reported for female participants in the abstract, and AUC values (0.69–0.72) demonstrate limited discriminatory power.