(PTFS08-07-24) Monitoring Body Composition in Pediatrics With 3D Optical Imaging: A Pilot Study

Objectives: The number of malnourished (under and over nourished) children and adolescents in the U.S. has increased sharply in recent decades. Diet and physical activity interventions have traditionally relied on weight or body mass index to monitor nutritional status; however, new recommendations include body composition to quantify of fat (FM) and fat-free mass (FFM). Three-dimensional optical (3DO) imaging is an emerging modality for body composition assessment and has been validated in cross-sectional children and adolescent samples. However, 3DO has not been evaluated for its accuracy longitudinally. Therefore, the objective of this study was to evaluate 3DO’s ability to monitor body composition over time.

Methods: A prospective analysis was performed using healthy children and adolescents that were enrolled and recalled as part of the Shape Up! Kids study. Each participant underwent DXA (Hologic Discovery/A system) and 3DO (Fit3D ProScanner) scans at baseline and follow-up. 3DO meshes were registered to a standardized template for vertex correspondence, transformed into principal components (PCs) with an established statistical shape model, and used to estimate whole-body and regional body composition outcomes using published equations. Body composition changes from 3DO were compared to DXA via linear regression. The least significant change (LSC) determined if the change in body composition was statistically significant with 95% confidence.

Results: The analysis included 18 participants (10 males). At baseline, participants were mean (SD) 10.5 (3.2) years old and ethnically diverse with a mean BMI z-score was 0.56 (1.29). On average, there was 1.5 years of growth between baseline and follow-up exam. Agreement between 3DO and DXA (R²) for changes in total FM, FFM, and appendicular lean mass, respectively, were 0.86, 0.84, and 0.78 with RMSEs of 2.09 kg, 3.12 kg, and 0.82 kg. Of the sample, 78% had a significant change in FM and FFM based on the LSC.

Conclusions: Compared to DXA, 3DO was sensitive in detecting body composition changes in children and adolescents over time. 3DO’s features of safety and growing accessibility can allow users, including parents, to monitor changes in body composition frequently without risk of ionizing radiation or high costs.

Funding Sources: NIH R01DK 111698