title: Relationship between dual-energy X-ray absorptiometry volumetric assessment and X-ray computed tomography-derived single-slice measurement of visceral fat.
abstract: To reduce radiation exposure and cost, visceral adipose tissue (VAT) measurement on X-ray computed tomography (CT) has been limited to a single slice. Recently, the US Food and Drug Administration has approved a dual-energy X-ray absorptiometry (DXA) application validated against CT to measure VAT volume. The purpose of this study was to develop an algorithm to compute single-slice area values on DXA at 2 common landmarks, L2/3 and L4/5, from an automated volumetrically derived measurement of VAT. Volumetric CT and total body DXA were measured in 55 males (age: 21-77 yr; body mass index [BMI]: 21.1-37.9) and 60 females (age: 21-85 yr; BMI: 20.0-39.7). Equations were developed by applying the relationship of CT single-slice area and volume measurements of VAT to the DXA VAT volume measure as well as validating these against the CT single-slice measurements. Correlation coefficients between DXA estimate of single-slice area and CT were 0.94 for L2/3 and 0.96 for L4/5. The mean difference between DXA estimate of single-slice area and CT was 5 cm(2) at L2/3 and 3.8 cm(2) at L4/5. Bland-Altman analysis showed a fairly constant difference across the single-slice range in this study, and the 95% limits of agreement for the 2 methods were -44.6 to +54.6 cm(2) for L2/3 and -47.3 to +54.9 cm(2) for L4/5. In conclusion, a volumetric measurement of VAT by DXA can be used to estimate single-slice measurements at the L2/3 and the L4/5 landmarks.
authors.affiliation: GE Healthcare Lunar, Madison, WI, USA. Electronic address: Yi.Xia@ge.com.
authors.forename: Yi
authors.initials: Y
authors.lastname: Xia
authors.affiliation: GE Healthcare Lunar, Madison, WI, USA.
authors.forename: David L
authors.initials: DL
authors.lastname: Ergun
authors.affiliation: GE Healthcare Lunar, Madison, WI, USA.
authors.forename: Wynn K
authors.initials: WK
authors.lastname: Wacker
authors.affiliation: Applied Statistics Laboratory, GE Global Research Center, Niskayuna, NY, USA.
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
authors.affiliation: Computational Biology and Biostatistics Laboratory, GE Global Research Center, Niskayuna, NY, USA.
authors.forename: Cynthia E
authors.initials: CE
authors.lastname: Davis
authors.affiliation: Cardiovascular Medicine Division, Oregon Health and Sciences University, Portland, OR, USA.
authors.forename: Sanjiv
authors.initials: S
authors.lastname: Kaul
mesh_terms: D015502:Absorptiometry, Photon; D050154:Adiposity; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D015992:Body Mass Index; D015331:Cohort Studies; D005260:Female; D006801:Humans; D050152:Intra-Abdominal Fat; D008159:Lumbar Vertebrae; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012737:Sex Factors; D014057:Tomography, X-Ray Computed; D055815:Young Adult
keywords: X-ray computed tomography; dual-energy X-ray absorptiometry; visceral fat