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  • 1
    ISSN: 1433-2965
    Keywords: Bone mineral measurements ; Broadband ultrasonic attenuation ; Ultrasound
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We report a study of broadband ultrasonic attenuation (BUA) in the calcaneus in 248 women. Measurements were performed with a Walker-Sonix UBA-575 ultrasonic bone analyser. The populations studied were 15 healthy young volunteers (group 1, mean age 26 years), 200 healthy pre- and postmenopausal women (group 2, mean age 53 years) and 33 osteoporotic women with vertebral crush fractures (group 3, mean age 66 years). Subjects in group 1 each had 10 repeated measurements of their right heel. Duplicate BUA measurements in the right heel were performed in 96 subjects and bilateral scans in a further 87 women in group 2. The remaining 17 subjects in group 2 and those in group 3 had a single scan of the right heel. All women in groups 2 and 3 had dual X-ray absorptiometry (DXA) scans of the lumbar spine and femoral neck. The precision study on the women in group 1 gave a root mean square (RMS) coefficient of variation (CV) of 4.2%. Individual CV results showed statistically significant differences (range 1.3%–7.6%). Duplicate scans in subjects in group 2 gave a RMS CV of 4.6% while the bilateral measurements showed no significant difference between the two heels. Linear regression analysis gave the following relationship between BUA and age: BUA=87.1−0.76 (Age −40) dB/MHz (r=−0.31,p〈0.001, SEE=14.0 dB/MHz). Multivariate regression analysis showed that, in addition to age, years since the menopause was also a significant factor in predicting BUA. In the first 5 years following the menopause BUA decreased by 2.5%/year, while in the next 5 years the decrease fell to 0.5%/year. The BUA measurements in the osteoporotic subjects in group 3 gave a mean T-score of −2.1 compared with 66 premenopausal normal women and a mean Z-score of −1.0 compared with 27 age-matched elderly normal women in group 2. In comparison the lumbar spine DXA measurements for the same women gave a mean T-score of −3.2 and a mean Z-score of −1.8. DXA therefore gave substantially better discrimination between osteoporotic and normal subjects than the BUA measurements.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1433-2965
    Keywords: Bone mineral measurement ; Dual-energy X-ray absorptiometry ; Longitudinal studies ; Supine lateral DXA
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We report a study to assess whether supine lateral dual-energy X-ray absorptiometry (DXA) scans of the lumbar spine provide better data for monitoring response to treatment than alternative measurement sites such as the posteroanterior (PA) spine, hip and total body. The study population was 152 women enrolled in a placebo-controlled clinical trial of cyclical etidronate therapy. All subjects were 1–10 years after the menopause with bone mineral density (BMD) between 0 and −2 SD of age-matched normal women. Paired PA and lateral spine, left hip and total-body DXA scans were performed at baseline, 1 year and 2 years on a Hologic QDR-2000. One hundred and thirty-one subjects completed the study. Mean percentage change from baseline at 2 years in the treated (n=61) and control (n=70) groups was calculated for vertebral body, width-adjusted (WA) vertebral body, mid-vertebral body and WA mid-vertebral body BMD measurements on the lateral scans and compared with the percentage changes in PA spine, femoral neck, trochanter, Ward's triangle and total-body BMD. The long-term precision for each BMD measurement site was obtained by linear regression analysis in subjects taking placebo. Overall treatment effect, defined as the difference in the percentage change in BMD in the two treatment groups at 2 years, was divided by long-term precision to give an index of the ability of each site to monitor response to treatment. Results (and standard errors) normalized to the ratio of treatment effect/precision for PA spine BMD were as follows: PA spine, 1.00; vertebral body, 0.89 (0.14); WA vertebral body, 0.78 (0.14); mid-vertebral body, 0.65 (0.14); WA mid-vertebral body, 0.60 (0.13); femoral neck, 0.35 (0.15); trochanter, 0.45 (0.15); Ward's triangle, 0.59 (0.22); total body, 0.52 (0.19). Although treatment effect was larger for lateral than for PA spine BMD, this advantage was offset by the greater precision errors. PA spine BMD remains the optimum measurement for longitudinal studies in recently postmenopausal women.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1432-0827
    Keywords: Bone mineral measurements ; Broadband ultrasonic attenuation ; Calcaneus ; Ultrasonic velocity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Measurements of broadband ultrasonic attenuation (BUA) and velocity of ultrasound through the heel (heel velocity, HV) were performed with a Contact Ultrasonic Bone Analyzer (CUBA-Research model) in 229 women. The subjects consisted of 16 healthy young volunteers (Group 1, mean age 26 years), 170 healthy pre- and postmenopausal women (Group 2, mean age 53 years), and 43 osteoporotic women with radiographically defined vertebral crush fracture (Group 3, mean age 66 years). Subjects in Group 1 had 10 repeated measurements in a study of short-term precision. Women in Groups 2 and 3 also had dual X-ray absorptiometry (DXA) scans to measure lumbar spine and femoral neck bone mineral density (BMD). The BUA and HV measurements for all 229 women showed a significant correlation (r = 0.75,P 〈 0.001). The precision study on the subjects in Group 1 gave a root mean square coefficient of variation of 6.3% for BUA and 1.04% for HV. Linear regression analysis gave the following relationship between BUA and age for the 170 normal women in Group 2: BUA = 83.6 − 0.86 (age 40) dB/MHz (r = −0.31,P 〈 0.001, SEE = 16.3 dB/MHz). The relationship between HV and age was as follows: HV = 1614 − 2.3 (age 40) m/s (r = −0.33,P 〈 0.001, SEE = 42 m/s). Multivariate regression analysis showed that in addition to age, years since the menopause was also a significant factor in determining both BUA and HV. In the first 5 years following the menopause, BUA and HV decreased by 2.2% and 0.3%/year, respectively, whereas in the next 10 years the rates of decrease fell to 0.5% and 0.03%/year. The BUA and HV measurements on the 43 osteoporotic subjects in Group 3 gave mean T-scores of −2.1 and −1.9 compared with 59 premenopausal women, and mean Z-scores of −1.3 and −0.9 compared with 26 age-matched normal women in Group 2, respectively. In comparison, the lumbar spine and femoral neck DXA measurements in the same subjects gave mean T-scores of −2.9 and −2.1 and mean Z-scores of −1.7 and −1.0, respectively. Lumbar spine BMD gave the best discrimination between women with osteoporotic vertebral fractures and normal subjects. However, the difference between the lumbar spine and BUA Z-scores was not statistically significant. Femoral neck BMD was equivalent to the ultrasound parameters in T-score and Z-score values.
    Type of Medium: Electronic Resource
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