Comparison of total-body measurements by dual-energy x-ray absorptiometry and dual-photon absorptiometry

Abstract

Both dual-photon absorptiometry (DPA) using 153Gd and dual-energy x-ray absorptiometry (DEXA) can be used for measurement of bone mineral content (BMC) and bone mineral density (BMD) of the total skeleton and its seven major regions. The short-term precision (coefficient of variation, CV) of DEXA for total-body BMD using the medium (20 minute) and fast (10 minute) speeds was 0.34 and 0.68% in 5 normal subjects; the corresponding CV in 5 osteoporotic females were 0.70 and 1.04%. The CV for BMD using DPA was 0.82% in 8 normal subjects and 0.70% in 12 osteoporotic patients. The CV for regional BMD using DPA was similar to fast-speed DEXA, without significant differences (p NS); precision with medium-speed DEXA was superior to DPA, and the differences were statistically significant (p less than 0.05) for head, spine, trunk, ribs, and pelvis. Total-body measurements using both DPA and DEXA were done on 99 subjects (84 females and 15 males). Significant correlations (r = 0.98; p less than 0.001) were found between DEXA and DPA measurements of both BMC and BMD. There were also significant correlations (r = 0.94-0.98; p less than 0.001) between DEXA and DPA measurements of anatomic regions (head, trunk, spine, pelvis, ribs, arms, and legs). DPA and DEXA results for BMD of total skeleton, ribs, pelvis, and legs were similar (p NS), and statistically significant differences were found in head, spine, and arm measurements (p less than 0.01, p less than 0.01, and p less than 0.05, respectively); regression equations allowed adjustment of DEXA values in patients already measured with the earlier DPA method.

Bone mineral status and bone loss over time in men with chronic systolic heart failure and their clinical and hormonal determinants

“…The precision of densitometric parameters was assessed by repeated DEXA measurements in 14 CHF patients (mean duration between assessments 4±1 days, range 2–7). Coefficients of variance for repeated measurements for all parameters were below 3%, which was in accordance with other studies showing a short‐term variability of <5% ,,…”

The 12-week progressive quadriceps resistance training improves muscle strength, exercise capacity and quality of life in patients with stable chronic heart failure

“…DEXA is a widely applied, non-invasive and reproducible method for the assessment of body composition, and involves only a minimal exposure to ionizing radiation [22].…”

Reduced bone mineral density in adult women diagnosed with menstrual disorders during adolescence

“…The T ‐ and Z ‐scores were estimated using mean BMD and SD values supplied by the Hologic equipment manufacturer. The reproducibility of the whole body BMD is calculated as <0.01 g/cm 2 or 0.1 SD (17), (18).…”