Validity of a new automated software program for visceral adipose tissue estimation

Introduction: Given the considerable time and research cost of analyzing biomedical images to quantify adipose tissue volumes, automated image analysis methods are highly desirable. Hippo Fat™ is a new software program designed to automatically quantify adipose tissue areas from magnetic resonance images without user inputs. Hippo Fat™ has yet to be independently validated against commonly used image analysis software programs. Objective: Our aim was to compare estimates of VAT (visceral adipose tissue) and SAT (subcutaneous adipose tissue) using the new Hippo Fat™ software against those from a widely used, validated, computer-assisted manual method (slice-O-matic version 4.2, Tomovision, Montreal, CA, USA) to assess its potential utility for large-scale studies. Methods: A Siemens Magnetom Vision 1.5-T whole-body scanner and a T1-weighted fast-spin echo pulse sequence were used to collect multiple, contiguous axial images of the abdomen from a sample of 40 healthy adults (20 men) aged 18-77 years of age, with mean body mass index of 29 kg/m² (range=19-43 kg/m²). Results: Hippo Fat™ provided estimates of VAT and SAT that were highly correlated with estimates using slice-O-matic (R ²>0.9). Average VAT was 9.4% lower and average SAT was 3.7% higher using Hippo Fat™ compared to slice-O-matic; the overestimation of SAT tended to be greater among individuals with greater adiposity. Individual-level differences for VAT were also substantial; Hippo Fat™ gave estimates of VAT ranging from 1184 cm ³ less to 566 cm³ more than estimates for the same person using slice-O-matic. Conclusion: Hippo Fat™ provides a rapid method of quantifying total VAT, although the method does not provide estimates that are interchangeable with slice-O-matic at either the group (mean) or individual level.