Program Book and Abstracts - ISCD

Poster Number 124
Central DXA
Use of External Quality Control Site for Validation of DXA Data
Sunil Wimalawansa, UMDNJ-RWJMS
Bone Mineral Density (BMD) can be measured at several skeletal sites, including the
lumber spine, femoral neck, total hip, and the forearm. Lumbar spine and dual hip
sites are routinely performed in most centers. Here we describe DXA studies done
o in 186 women over a five year period (a three year follow-up) using a GE-Luna
DXA Prodigy scanner. We have submitted a duplicate set of DXA scans to an
independent evaluation site for validation of data. These studies were done without
referring to the scanned-analyzed at the primary site; UMDNJ-RWJMS. Data
consisted of baseline, 6 months, 12 months, and 24 months. Complete set of data
from 36 months was not available at the time we send the DXA scans to the QA site.
Study group consist of postmenopausal women (13 months to 10 years since last
menses, and 18 percent was non-Caucasians. Half the women were within five years
of menopause and reminder were between 5 and 10 years since menopause.
Overall, study revealed a normal distribution of BMD across this study population.
Table below indicate the BMD values as analyzed at the primary site vs. data analyzed
at the independent quality assurance site.
Timing of # Subjects Mean SEM p value
BMD
Base Line
Pri. Site 186 1.0769 0.006 0.018
186* 1.0611 0.0052 0.51
QA site 179 1.0588 0.0061
12 months
Pri. Site 180 1.058 0.0069 0.912
180* 1.0576 0.006 0.693
QA site 180 1.0596 0.0067
6 months
Pri. Site 182 1.0765 0.0067 0.036
182* 1.0603 0.0059 0.91
QA site 180 1.0596 0.0065
24 months
Pri. Site 175 1.0573 0.0072 0.075
175* 1.0512 0.0066 0.245
QA site 175 1.0469 0.0069
Poster Number 125
Central DXA
The Importance of Lean Body Mass in Bone Mineral Density of Postmenopausal
Women
Mee-Ran Kim, The Catholic University of Korea
Objective: The aim of the study is to investigate the importance of lean body mass in
bone mineral density (BMD) of post-menopausal women.
Materials and methods: BMD of lumbar spine and both femur were measured with
Dual-Energy X-ray Absorptiometry (DXA), Lunar Prodigy Advance TM (GE
healthcare, United States of America) in 55 healthy, post-menopausal women, aged
between 50 and 77 years old. The candidates were selected from patients who visited
menopausal clinic in department of gynecology, Kangnam St. Mary’s hospital, Catholic
university of Korea. Lean body mass and fat mass of both arms, legs, trunk and BMD
of lumbar spine, both femur neck, trochanter were measured with DXA.
Results: The mean age was 57.19 ± 6.13 (range 50 - 77) years old, height 156 ± 5
cm, weight 57.82 ± 5.80 kg, body mass index 23.73 ± 2.42. In post-menopausal
women, percentage of android fat mass (42.84 ± 6.12%) was higher than that of
gynoid fat mass (39.57 ± 4.37%). There was negative correlation between BMD of
both femur and android fat mass, total fat mass. Each fat mass of arms, legs, trunk
and gynoid fat mass showed no significant correlation with BMD. Lean body mass of
legs, trunk had significant correlation with BMD of lumbar and femur, although that
of arms did not.
Conclusion: Body fat mass had little significance in correlation with BMD, except for
android and total fat mass of the body, which had negative correlation with femur
BMD. Lean body mass of legs, trunk showed significant relation with BMD. In
conclusion, as android fat mass and total fat mass decrease, BMD increases and lean
body mass of legs, trunk increase, BMD increases. Therefore, it will be helpful for
increasing BMD to do adequate exercise in order to increase lean body mass in
post-menopausal women.
Data revealed a non-statistical slightly higher BMD data for the entire group in the
primary site in comparison to the QA site. In part this was due to the noncorrection
of the repeat scans to the base line scan positioning using the copy
feature of the GE-Lunar GE machine. Corrections of this using the copy-feature
lead to virtually identical results between the two
groups of analysis. In conclusion, the data generated
from the GE-Lunar Prodigy DXA machine is highly
accurate, as indicated by this comparison of data
from an independent DXA quality assurance site. In
follow-up DXA scans, if one uses built-in copy
feature and position patients correctly, there is no
need to have external quality assurance program to
validate DXA data.
Poster Number 126
Central DXA
Body Composition Assessment Using Siri Underwater Equivalent Percent
Fat Assessed by Norland Equipment
Chad Dudzek, Norland—a CooperSurgical Company; George Ekker, Norland—a
CooperSurgical Company; Kathy Dudzek, Norland—a CooperSurgical Company; Tom
Sanchez, Norland—a CooperSurgical Company
Assessment of body composition by DXA is showing significant interest in the clinical
community. The current study examines effectiveness of the Norland based DXA Siri
Underwater Equivalent Percent Fat to reflect clinically labeled conditions of
Underfat, Healthy, Overfat and Obese. A population of 150 subjects (75 males
between 20 and 77 years old with a Body Mass Index between 16.0 and 42.8 and
75 females between 20 and 74 years old with a Body Mass Index between 17.3 and
41.9) underwent whole body studies using a Norland XR-46 fitted with Illuminatus
software. Careful measurements of height and weight were also obtained immediately
before scanning. The accuracy of DXA measurements in these subjects was
confirmed by comparing the total body weight measured by DXA (bone mass +
lean mass + fat mass) to the total body weight measured by scale (y = 0.9931x +
0.599, r=0.9993, p