Measurement of visceral fat thickness by ultrasound and comparison with visceral fat area determinations

Introduction: Visceral fat quantity is an important factor in the prediction of the cardiovascular risk of obesity. The „gold standard“ of its measurement is the determination by CT. However, the exposure to ionizing radiation, high cost and low availability put limits to the routine use of CT for this purpose. Ultrasonography (US) is a simple, readily available, low-cost method for the measurement of visceral fat thickness (VFT) which correlates well with the CT data, according to the literature. Another simple and available method is the bioimpedance measurement of visceral fat area (VFA). Purpose: Comparison of VFT and VFA measurements and further study of correlations betveen VFT and US attenuation of the liver, subcutaneous fat thickness (SCF), body mass index (BMI) and serum lipid data. Material and methods: Number of patients: 201 (85 males, 116 females), mean age 44.1yrs. The US examinations were done by using a B-K Medical Hawk 2102 EXL scanner, the bioimpedance measurements were made by Biospace InBody 720 body composition analyser. Results: The mean VFT values increase parallel with BMI: in patients with BMI<25, 13±4.5cm; 25 ≤ BMI<29.9, 25.1±3.6cm; 30 ≤ BMI<39.9, 41.3±6.2cm and BMI ≥40, 81.9±22.9cm. Significant correlations (p<0.001) were found between VFT and VFA, BMI, SCF and some other parameters. On the other hand, no correlations were found between VFT and the liver attenuation and lipid values. Conclusions: On the basis of our studies it can be concluded that A) VFT and VFA values correlate significantly; B) US measurement of VFT is suitable for determination of abdominal fat quantity; C) The presence of fatty liver disease associated with high US attenuation values is not conclusively connected with increase of visceral fat.