Poster Topical Area: Obesity
Location: Hall D
Poster Board Number: 665
Objectives: Ultrasound(US) is an emerging modality for abdominal fat distribution (AFD) assessment, but a preferred protocol has not been identified. Here, we examine the agreement between a published US technique and CT to assess subcutaneous (SAT), superficial (SSAT) and deep (DSAT) thickness using a portable, tablet compatible ultrasound at the level of the umbilicus.
Methods: We conducted a pilot study to compare the agreement of SAT, SSAT and DSAT thickness (cm) measurements via US and CT on 14 subjects. Subjects were consented and measured at the umbilicus adhering to a previously published US technique at 5cm right(R) and left(L) of umbilicus. Two thickness measurements for SAT and SSAT were taken and averaged. DSAT was calculated by subtracting SSAT from SAT. CT scans for medical reasons were performed on same day of US. A blinded radiologist selected a single-cross sectional CT image at L4 from each subject and measured thickness 5cm lateral on either side of umbilicus according to US protocol. Data presented as mean ± standard deviation.
Results: Mean age was 61.3±15.6 years, 64% (9/14) were Non-Hispanic Whites and 57% (8/14) were male. For US, R-SSAT=1.2±0.9cm vs L-SSAT=1.2±0.9cm and R-DSAT=1.2±0.8cm vs L-DSAT=1.1±0.8cm, respectively. For CT, R-SSAT=1.1±0.7cm vs L-SSAT=0.95±0.6cm and R-DSAT=1.3±0.8cm vs L-DSAT=1.2±0.1cm. SAT, SSAT, and DSAT for US vs. CT was 3.4±1.9 vs 3.6±1.9cm, 1.6±1.0 vs 1.8±1.3cm, and 1.9±1.5 vs 1.7±1.2cm, respectively. Agreement was strong based on Cohen's kappa criteria (strong agreement= 0.8-0.9) using Lin's concordance (LCC)>0.81, intra-class correlation coefficient (ICC)>0.9, and Spearman's rho (SR)>0.87. ICC for SAT, SSAT and DSAT was 0.96 (p
Conclusion: Our findings confirm that thickness measurements taken with a portable, tablet-compatible ultrasound at bedside was highly comparable to that obtained by CT. This portable US and thickness assessment of AFD using published protocol has potential for enabling clinicians and researchers to assess body composition in non-clinical and/or outpatient settings where CT is less acceptable for research use.
Rush University Medical Center