Alexander Schaudinn MD, Presenter: Nothing to Disclose

Nicolas Linder, Abstract Co-Author: Nothing to Disclose

Nikita Garnov, Abstract Co-Author: Nothing to Disclose

Matthias Bluher MD, Abstract Co-Author: Nothing to Disclose

Thomas Kurt Kahn MD, Abstract Co-Author: Nothing to Disclose

Harald F. Busse PhD, Abstract Co-Author: Nothing to Disclose

Abdominal fat, in particular visceral adipose tissue (VAT), is associated with an increased risk for metabolic and cardiovascular diseases. MRI is well suited for volumetry but data processing is typically laborious and time-consuming. The goal was to evaluate how fast and how accurate a heavily reduced analysis can predict total abdominal VAT volume.

129 obese patients (90 F, 39 M, mean BMI=34.8 kg/m²) underwent 1.5 T MRI (Philips Achieva XR) as part of an IRB-approved study of the effects of different training regimens on visceral fat. MRI volumetry relied on a two-point Dixon sequence (50 slices, thickness 10 mm, gap 0.5 mm, acquisition time 160 s plus breathing intervals). A software tool was used for semiautomatic VAT segmentation of the abdominopelvic region. VAT volumes extrapolated from single slices (VAT1) or blocks of five adjacent slices (VAT5) and centered at spinal landmarks (lumbar discs L1/L2–L5/S1) were compared with total VATT volume (from diaphragm to pelvic floor, reference value). Statistical measures of agreement were the coefficient of determination R² of a linear regression through the origin as well as the standard deviations σ1(5) of the differences between VAT1(5) and VATT (Bland-Altman analysis).

Analysis of total VAT (mean of 37 slices), VAT5 and VAT1 took an average of 24, 4 and 2 min per patient, respectively. Average VATT volumes were 2.9 (0.9-6.0) L for females and 6.2 (2.5 to 11.2) L for males. Resulting accuracy varied with disc level and showed best agreement at L2/L3 for both genders. Estimates of VAT5 were generally more accurate than those of VAT1 (σ5 vs. σ1): 460 vs. 526 ml (R²=0.85 vs. 0.82) for females and 643 vs. 726 ml (R²=0.93 vs. 0.91) for males. Corresponding coefficients of variation (COV) were 15.9% for females and 10.4% for males.

Five-slice volume estimates at the level of lumbar disc L2/L3 can be obtained within 4 min and were a reliable predictor for abdominopelvic VAT volume in adipose patients, independent of gender. One-slice estimates took only 2 min and were slightly less accurate.

Visceral adipose tissue volume, a potential risk factor for adipose patients, can be reliably estimated in clinically acceptable time by reduced analysis of five slices around lumbar disc L2/L3 for both genders.

Schaudinn, A, Linder, N, Garnov, N, Bluher, M, Kahn, T, Busse, H, Time-effective MRI-based Quantification of Visceral Adipose Tissue (VAT) in Adipose Patients.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14013665.html