Objective: Visceral adipose tissue (VAT) is a significant risk factor for obesity-related metabolic diseases. This study investigates (1) the best single CT slice location for predicting total abdominal VAT volume in paediatrics and (2) the relationship between waist circumference (WC), sagittal diameter (SD), gender and VAT volume. Methods: A random sample of 130 paediatric abdomen CT scans, stratified according to age and gender, was collected. Three readers measured VAT area at each intervertebral level between T12 and S1 using ImageJ analysis (National Institute of Health, Bethesda, MD) software by thresholding 2190 to 230 HU and manually segmenting VAT. Single-slice VAT measurements were correlated with total VAT volume to identify the most representative slice. WC and SD were measured at L3-L4 and L4-L5 slices, respectively. Regression analysis was used to evaluate WC, SD and gender as VAT volume predictors. Results: Interviewer and intraviewer reliability were excellent (intraclass correlation coefficient 5 0.99). Although VAT measured at multiple slices correlated strongly with abdominal VAT, only one slice in females at L2-L3 and two slices in males at L1-L2 and L5-S1 were strongly correlated across all age groups. Linear regression analysis showed that WC was strongly correlated with VAT volume (beta 5 0.970, p , 0.001). Conclusion: Single-slice VAT measurements are highly reproducible. Measurements performed at L2-L3 in females and L1-L2 or L5-S1 in males were most representative of VAT. WC is indicative of VAT. Advances in knowledge: VAT should be measured at L2-L3 in female children and at either L1-L2 or L5-S1 in males. WC is a strong indicator of VAT in children.
INTRODUCTIONThe prevalence of obesity has increased dramatically over the past 30 years and was recently described by the World Health Organization as a "global epidemic".1 In 1980, 7% of children aged 6-11 years were obese compared with nearly 18% in 2012. Similarly, the percentage of adolescents aged 12-19 years who were obese increased from 5% to almost 21% over the same period.2 The Centers for Disease Control (CDC) and Prevention classifies overweight children as those with a body mass index (BMI) over the 85th percentile and obese children as those with BMI over the 95th percentile relative to a child's age and sex. Currently, more than one-third of children and adolescents are overweight or obese, related to the sex-specific CDC BMI-for-age growth charts from 2000.