Comparison of Abdominal Visceral Adipose Tissue Measurements in Adolescents between Magnetic Resonance Imaging and Dual-energy X-ray Absorptiometry

Excess abdominal visceral adipose tissue (VAT) is associated with cardiometabolic risk factors in adolescents. VAT is mainly measured using Magnetic Resonance Imaging (MRI), yet dual-energy x-ray absorptiometry (DXA) is more affordable and available. The purpose was to compare adolescent VAT values obtained by MRI and DXA. A sample of 330 adolescents 10–16 years of age were recruited (52.3% female, 58.5% White). Abdominal VAT was measured using a General Electric (GE) Signal MRI Excite scanner with imaging software. A whole-body DXA (GE iDXA) scan was performed, and software calculated VAT within the android region. Wilcoxon signed-rank t-tests were used to determine differences between VAT values, within sex, race (White, African American, and Other race), and BMI categories (normal weight, overweight, and obese). VAT values from MRI and DXA were significantly correlated (r=0.78, p<0.001). Average VAT from MRI (0.54±0.43 kg) was significantly higher than VAT from DXA (0.33±0.39 kg) in the overall sample (p<0.001) and within all subgroups (p<0.001). All standardized values between the two measurements fell within ±1.96 standard deviations, and differences between the methods were not associated with level of VAT. In this sample, DXA values were correlated with MRI values, but DXA consistently underestimated VAT compared to MRI.