Abstract Background Dual-energy X-ray absorptiometry (DXA) allows clinically relevant measurement of bone mineral density (BMD) at central and appendicular skeletal sites, but DXA has a limited ...ability to assess bone geometry and cannot distinguish between the cortical and trabecular bone compartments. Quantitative computed tomography (QCT) can supplement DXA by enabling geometric and compartmental bone assessments. Whole-body spiral CT scanners are widely available and require only seconds per scan, in contrast to peripheral QCT scanners, which have restricted availability, limited spatial resolution, and require several minutes of scanning time. This study evaluated the accuracy and precision of whole-body spiral CT scanners for quantitatively assessing the distal radius, a common site of non-vertebral osteoporosis-related fractures, and compared the CT-measured densitometric values with those obtained from dual-energy-X-ray absorptiometry. Subjects and methods A total of 161 postmenopausal women with baseline lumbar spine BMD T -scores between − 1.0 and − 2.5 underwent left forearm QCT using whole-body spiral CT scanners twice, 1 month apart. QCT volumes of interest were defined and analyzed at 3 specific radial regions: the ultradistal region by using slices at 8, 9, and 10 mm proximal to the ulnar styloid tip; the distal region by a slice 20 mm proximal; and the middle region by a slice 40 mm proximal. BMD, bone mineral content (BMC), volume, and average cortical thickness and circumference were measured. We evaluated QCT accuracy and precision and also report correlations between QCT and DXA for BMD and BMC. Results Overall accuracy and precision errors for BMD, BMC and volume were consistent with known skeletal QCT technology precision and were generally less than 3%. BMD and BMC assessed by QCT and DXA were correlated ( r = 0.55 to 0.80). Discussion Whole-body spiral CT scanners allow densitometric evaluations of the distal radius with good accuracy and very good precision. This original and convenient method provides a tool to further investigate cortical and trabecular bone variables in the peripheral skeleton in osteoporotic patients. These assessments, coupled with evaluation of the effects on cortical and trabecular bone measured in response to therapies for osteoporosis, may advance our understanding of the contributors to non-vertebral fracture occurrence.
Since the discovery of cortisol and the synthesis of related compounds, these potent pharmacologic agents have been progressively
more widely utilized in allergic, pulmonary, and rheumatologic ...conditions. Organ transplantation represents a new group of
patients added to the already large pool of subjects receiving glucocorticoids. However, glucocorticoids cause major side
effects involving several organ systems, including the cardiovascular, endocrine, gastrointestinal, ophthalmologic, and musculoskeletal
systems. Among the most dramatic side effects is the development of glucocorticoid-induced osteoporosis. Glucocorticoid use
in the treatment of chronic obstructive pulmonary disease accounts for the majority of male patients with osteoporosis seen
in our mineral metabolism clinic. This article focuses on glucocorticoid-induced osteoporosis in the adult with an emphasis
on the clinical aspects of this condition. It is intended not as an extensive review on the subject but as a practical guide
to help clinicians prevent and treat this condition in adult patients.
PDF
