For measurement of the degree of osteoporosis, various methods have been used. The Saville's index of the lumbar spine is very simple method. With the object of studying the reliability and clinical usefulness of Saville's index, authors compared the Saville's index with anteroposterior(A.P.) and lateral Dual x-ray absorptiometry, and the Singh's index with the anteroposterior D.X.A. We took the D.X.A. and simple lumbar spine lateral view in 124 patients in same time and also performed D.X.A. and both hips anteroposterior views in 112 patients, then analyzed the correlation between the A.P. and lateral D.X.A., Saville's index and D.X.A., Singh's index and D.X.A. The results were as follows. 1. The correlation coefficient of the A.P. and lateral D.X.A. was 0.46 and appeared the low degree of correlation. 2. The correlation coefficient of the A.P. and lateral D.X.A. compared with Saville's index were 0.68 and 0.83, respectively. Saville's index appeared the higher correlation in lateral D.X.A. than A.P. D.X.A. 3. The correlation coefficient of Singh's index and D.X.A. was 0.84, appeared nearly the same results of Saville's index with lateral D.X.A. 4. Intrapersonal differences were 36% in Saville's index, 28% in Singh's index. Saville's index appeared higher intrapersonal error than Singh's index. The lateral D.X.A. is more accurate and precise method than A.P. D.X.A. because lateral D.X.A. reduces the influence of soft tissue calcification and degenerative changes of spine. As Saville's index is a grading method based on lateral view of lumbar spine, we think that it should be compared with the lateral D.X.A. Regarding this results, authors suggest that Saville's index is not any accurate measurement of bone quantity, but has clinical usefulness for evaluation of osteroporosis.
Absorptiometry, Photon ; Bone Density ; Hip ; Humans ; Methods ; Osteoporosis ; Spine

PURPOSE: Dual-energy X-ray imaging is widely used today in various areas of medicine and in other applications. However, no similar technique exists for dental applications. In this study, we propose a dual-energy technique for dental diagnoses based on voltage-switching. MATERIALS AND METHODS: The method presented in this study allowed different groups of materials to be classified based on atomic number, thereby enabling two-dimensional images to be colorized. Computer simulations showed the feasibility of this approach. Using a number of different samples with typical biologic and synthetic dental materials, the technique was applied to radiographs acquired with a commercially available dental X-ray unit. RESULTS: This technique provided a novel visual representation of the intraoral environment in three colors, and is of diagnostic value when compared to state-of-the-art grayscale images, since the oral cavity often contains multiple permanent foreign materials. CONCLUSION: This work developed a technique for two-dimensional dual-energy imaging in the context of dental applications and showed its feasibility with a commercial dental X-ray unit in simulation and experimental studies.
Absorptiometry, Photon ; Computer Simulation ; Dental Materials* ; Diagnosis ; Methods ; Mouth ; Radiographic Image Enhancement

Manifold methods for bone mineral density analyses are introduced in this paper, and the characteristics of precision, accuracy, position, convenience, sensitivity and the radiation hazards of these methods are also discussed here.
Absorptiometry, Photon ; methods ; Bone Density ; Humans ; Osteoporosis ; diagnosis ; Sensitivity and Specificity ; Tomography, X-Ray Computed ; Ultrasonography ; instrumentation

OBJECTIVE: Use of quantitative computed tomography (CT) to evaluate bone mineral density was suggested in the 1970s. Despite its reliability and accuracy, technical shortcomings restricted its usage, and dual-energy X-ray absorptiometry (DXA) became the gold standard evaluation method. Advances in CT technology have reduced its previous limitations, and CT evaluation of bone quality may now be applicable in clinical practice. The aim of this study was to determine if the Hounsfield unit (HU) values obtained from CT correlate with patient age and bone mineral density. METHODS: A total of 128 female patients who underwent lumbar CT for back pain were enrolled in the study. Their mean age was 66.4 years. Among them, 70 patients also underwent DXA. The patients were stratified by decade of life, forming five age groups. Lumbar vertebrae L1-4 were analyzed. The HU value of each vertebra was determined by averaging three measurements of the vertebra's trabecular portion, as shown in consecutive axial CT images. The HU values were compared between age groups, and correlations of HU value with bone mineral density and T-scores were determined. RESULTS: The HU values consistently decreased with increasing age with significant differences between age groups (p<0.001). There were significant positive correlations (p<0.001) of HU value with bone mineral density and T-score. CONCLUSION: The trabecular area HU value consistently decreases with age. Based on the strong positive correlation between HU value and bone mineral density, CT-based HU values might be useful in detecting bone mineral diseases, such as osteoporosis.
Absorptiometry, Photon* ; Back Pain ; Bone Density* ; Female ; Humans ; Lumbar Vertebrae ; Methods ; Osteoporosis ; Spine*

In order to meet the requirements of ultrasound bone density measurement, we designed a sofware based on Visual Studio C+ + 2008. The software includes interface design, acquisition and control, data processing and parameter extraction, data storage and printing. Excellent human-computer interface (HCI) will give users a convenient experience. Auto gain control (AGC) and digital filter can improve the precision effectively. In addition, we can observe waveform clearly in real time. By using USB communication, we can send control commands to the acquisition and get data effectively, which can shorten the measuring time. Then we calculated the speed of sound (SOS) and broadband ultrasound attenuation (BUA). Patients' information can be accessed by using XML document. Finally, the software offers printing function.
Absorptiometry, Photon ; instrumentation ; Bone Density ; Humans ; Information Storage and Retrieval ; Software ; Sound ; Ultrasonics ; methods ; User-Computer Interface

Osteoporotic vertebral fractures are associated with increased morbidity and mortality. Morbidity associated with these fractures includes pain and decreased physical function, which have a significant impact on the quality of life. The detection of osteoporotic vertebral fracture is based mainly on the identification of vertebral collapse, but this can be misleading in the presence of a fracture without radiologic collapse. And the diagnosis of vertebral fractures in simple radiographs is difficult because of normal variants and degenerative change of vertebrae. We review the various methods for evaluating osteoporotic vertebral fractures based on simple radiography or dual-energy X-ray absorptiometry (DXA). The preferred method may be Genant's semiquantitative method which was developed in an attempt to reduce subjectivity associated with visual diagnosis of osteoporotic vertebral fracture. Recently, vertebral fracture assessment (VFA) by DXA can be used to detect vertebral fractures in asymptomatic patients undergoing routine BMD measurements. Yoshida's classification is useful alternative method in the incidental vertebral fracture diagnosis with a morphological change in the anterior bone cortex.
Absorptiometry, Photon ; Classification ; Diagnosis ; Humans ; Methods ; Mortality ; Osteoporosis ; Quality of Life ; Radiography ; Spinal Fractures ; Spine

Objective To compare the consistency of quantitative ultrasound(QUS)and dual-energy X-ray absorptiometry(DXA)in measuring bone mineral density(BMD)of adults aged 18-40 years in Guangzhou and evaluate the diagnostic value of QUS for identifying low bone mass.Methods DXA was employed to measure the BMD and QUS to measure the speed of sound(SOS)in 731 participants.The Bland-Altman analysis was performed to evaluate the consistency of Z scores between SOS and BMD.With the BMD Z ≤-2.00 as the diagnostic criterion for low bone mass,the receiver operating characteristics curve of QUS was established,and the area under the curve(AUC)and the sensitivity,specificity,and correct diagnostic index for the optimal cut-off of SOS Z score were calculated.Results The results of Bland-Altman analysis showed that the mean differences in the Z scores of SOS and BMD in males and females were 1.27(-0.94 to 3.47)and 0.93(-1.33 to 3.18),respectively.The AUC of SOS Z score in the diagnosis of low bone mass in males and females was 0.734(95%CI=0.380-0.788)and 0.679(95%CI=0.625-0.732),respectively.In males,the optimal cut-off of SOS Z score for low bone mass was -0.35,with the sensitivity,specificity,and correct diagnostic index of 64.1%,68.6%,and 0.327,respectively.In females,the optimal cut-off value of SOS Z scores for low bone mass was -1.14,with the sensitivity,specificity,and correct index of 73.9%,54.8%,and 0.285,respectively.Conclusion QUS and DXA show poor consistency in the diagnosis of BMD in the adults aged 18-40 years in Guangzhou,while QUS demonstrates an acceptable value in identifying low bone mass.
Male ; Female ; Adult ; Humans ; Absorptiometry, Photon/methods* ; Bone Density ; Ultrasonography ; Bone and Bones ; ROC Curve ; Sensitivity and Specificity

OBJECTIVES: The purpose of this study was to evaluate the effects of hyperthyroidism and their etiology on bone mineral density (BMD), on body soft tissue composition, on the prevalence of vertebral fractures detected by vertebral fracture assessment (VFA) and on the trabecular bone score (TBS). METHODS: From an initial population of 119 Portuguese men (78 with hyperthyroidism [HT]+ 41 controls [CTs]) admitted to the Endocrinology Department we selected 41 men aged over 50 with clinical hyperthyroidism to participate; each one was matched by age and height with a control person. BMD (g/cm²) at the lumbar spine, hip, radius 33% and whole body and the total body masses (kg) were studied by dual-energy X-ray absorptiometry (DXA). VFA with Genant semiquantitative method was used to detect fractures. The TBS was obtained from lumbar spine DXA images. No patient had been treated previously for hyperthyroidism or osteoporosis. Adequate statistical tests were used. RESULTS: In the hyperthyroidism group, total lean mass (CT 58.16 ± 7.7 vs. HT 52.3 ± 5.7, P = 0.03) and distal radius BMD (CT 0.769 ± 0.05 vs. HT 0.722 ± 0.08, P = 0.005) were lower; there was a significantly higher prevalence of osteoporosis (CT 9.7% vs. HT 29.3%, P = 0.015) and vertebral fractures (CT 2.4% vs. HT 24.4%, P = 0.007). TBS was similar in both groups (CT 1.328 ± 0.11 vs. HT 1.356 ± 0.11, P = not significant). Comparing patients with Graves' disease with patients with toxic goiter, there were no differences regarding BMD, BMD qualification, prevalence of fractures and TBS and just total lean mass was significantly lower in patients with Graves' disease. CONCLUSIONS: These results suggest that in a group of hyperthyroid men aged over 50 there are significant decreases in cortical bone BMD and lean mass and a higher prevalence of osteoporosis and silent vertebral fractures, but the etiology of the hyperthyroidism does not seem to influence it. Besides the antithyroid drugs, some patients may benefit from bone-directed treatments.
Absorptiometry, Photon ; Antithyroid Agents ; Bone Density ; Endocrinology ; Goiter ; Graves Disease ; Hip ; Humans ; Hyperthyroidism* ; Male ; Methods ; Osteoporosis* ; Prevalence* ; Radius ; Spine

BACKGROUNDThe performance of computed tomography X-ray absorptiometry (CTXA) against the dual energy X-ray absorptiometry (DXA) as standard has not been studied in Chinese population. The aim of this study was to evaluate the precision of this measurement and validate the value of quantitative computed tomography (QCT) by comparing CTXA results with DXA results in an elderly Chinese population.

METHODSOne hundred and three females of 46 to 76 years old and 49 males of 52 to 76 years old were recruited from the Prospective Urban Rural Epidemiology study. All subjects underwent hip scans by both QCT and DXA on the same day. For precision determination, 30 subjects had duplicate DXA hip scans. The hip QCT data of a subset of 27 subjects were separately analyzed by two observers and reanalyzed by one observer at a different time. The inter- and intra-observer variations of CTXA measurement were assessed, and the difference and correlation between CTXA and DXA results were analyzed.

RESULTSThe inter- and intra-observer variations of CTXA were 0.070 and 0.024 g/cm(2) in the femoral neck (FN), and 0.030 and 0.012 g/cm(2) in the total hip (TH), which were comparable to the DXA inter-scan variations (0.013 g/cm(2) for FN and 0.014 g/cm(2) for TH). The results of CTXA bone mineral density (BMD) were highly correlated with those of DXA (R(2) = 0.810 for FN and R(2) = 0.878 for TH). The BMD values of CTXA in FN and TH were lower than those of DXA by 21.0% and 17.8% (P < 0.05), respectively. However, after appropriate transformation, the difference was eliminated and a comparable T score could be obtained.

CONCLUSIONSCTXA shows good agreement with DXA for the measurement of BMD in the proximal femur, which makes QCT suitable for the quantification of bone mineral content in the hip and helpful for the diagnosis of osteoporosis.

Absorptiometry, Photon ; methods ; Aged ; Bone Density ; physiology ; Female ; Humans ; Male ; Middle Aged ; Osteoporosis ; diagnosis ; diagnostic imaging ; Tomography, X-Ray Computed

OBJECTIVETo measure hip bone mineral density (BMD) on different femoral rotations and to identify the influence of femoral rotation during hip densitometry.

METHODSForty women were recruited at the out-department of orthopedic, with the average age of 60.7 years (45-85 years), the average height of 161.8 cm (150-175 cm), and the average weight of 67.4 kg (48-80 kg). BMD measurement of hip was done in neutral position (0 degrees), 15 degrees and 30 degrees of internal rotation under quality control of DXA machine. All the subjects were asked to get down scan table and reposition after each measuring in different rotation.

RESULTSHip BMD of proximal femur (femoral neck, Ward's area and trochanter region) have significant variations in measurement (P < 0.01) among neutral position, 15 degrees and 30 degrees of internal rotation. There were more BMD change at the cancellous region (Ward's triangle and trochanter region) than at cortical bone area (femoral neck region). Statistical analysis showed a significant positive correlation for hip BMD change between neutral degrees to 15 degrees of internal rotation and 15 degrees to 30 degrees of internal rotation. But no correlation between neutral degrees to 30 degrees of internal rotation for hip BMD change.

CONCLUSIONSFemoral rotation was shown to have a significant effect on hip BMD measurements. Cortical bone region of hip have a less BMD change than cancellous bone region. Proper positioning of the femur during scan can improve precision significantly.

Absorptiometry, Photon ; methods ; Aged ; Aged, 80 and over ; Bone Density ; Female ; Femur ; Hip ; Humans ; Middle Aged ; Posture ; Rotation