title: Single slice vs. volumetric MR assessment of visceral adipose tissue: reliability and validity among the overweight and obese.
abstract: Visceral adipose tissue (VAT) is associated with abnormal cardiovascular and metabolic profiles. Total VAT volume of the abdominal compartment by magnetic resonance imaging (MRI) is the gold-standard measurement for VAT but is costly and time consuming. Prior studies suggest VAT area on a single slice MR image may serve as a surrogate for total VAT volume but it is unknown if this relationship is maintained in overweight and obese men and women. Untreated sleep apnea subjects enrolled into the Icelandic Sleep Apnea Cohort (ISAC) underwent abdominal MRI. VAT area and subcutaneous adipose tissue (SAT) area at the L2-L3 and L4-L5 interspaces and total VAT and SAT volumes were determined by manual examination using image analysis software; 539 men and 129 women with mean ages of 54.1 and 58.8 years and mean BMI of 32.2 kg/m(2) and 33.7 kg/m(2), respectively, were studied. Mean total VAT volume was 40% smaller and mean total SAT was 25% larger among females compared with males. The correlation with VAT volume was significantly larger for L2-L3 VAT area (r = 0.96) compared to L4-L5 VAT area (r = 0.83). The difference in correlation coefficients was statistically significant (nonparametric bootstrap P < 0.001 with 95% confidence interval (CI) for the difference from 0.11 to 0.15. VAT area at L2-L3 was also significantly better correlated with VAT volume than traditional anthropometric variables. Linear regression analyses demonstrated that L2-L3 area alone was sufficient for predicting total VAT volume and that the nature of the linear association was maintained across all levels of obesity and in both genders.
authors.affiliation: Center for Sleep and Circadian Neurobiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA. fgm@mail.med.upenn.edu
authors.forename: Greg
authors.initials: G
authors.lastname: Maislin
authors.forename: Murtuza M
authors.initials: MM
authors.lastname: Ahmed
authors.forename: Nalaka
authors.initials: N
authors.lastname: Gooneratne
authors.forename: Matt
authors.initials: M
authors.lastname: Thorne-Fitzgerald
authors.forename: Christopher
authors.initials: C
authors.lastname: Kim
authors.forename: Karen
authors.initials: K
authors.lastname: Teff
authors.forename: Erna S
authors.initials: ES
authors.lastname: Arnardottir
authors.forename: Bryndis
authors.initials: B
authors.lastname: Benediktsdottir
authors.forename: Hildur
authors.initials: H
authors.lastname: Einarsdottir
authors.forename: Sigurdur
authors.initials: S
authors.lastname: Juliusson
authors.forename: Allan I
authors.initials: AI
authors.lastname: Pack
authors.forename: Thorarinn
authors.initials: T
authors.lastname: Gislason
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Schwab
mesh_terms: D015992:Body Mass Index; D003362:Cost-Benefit Analysis; D005260:Female; D006801:Humans; D007055:Iceland / Q000453:epidemiology; D050152:Intra-Abdominal Fat / Q000473:pathology*; D016014:Linear Models; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009333:Neck; D009765:Obesity / Q000453:epidemiology / Q000473:pathology*; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012307:Risk Factors; D012891:Sleep Apnea Syndromes / Q000453:epidemiology / Q000473:pathology*; D055105:Waist Circumference