Digital orthopantomograms in osteoporosis detection: mandibular density and mandibular radiographic indices as skeletal BMD predictors

Objectives:

To determine the correlation of skeletal bone mineral density (BMD) with mandibular density and mandibular radiographic indices estimated on digital panoramic radiographs.

Methods:

Study comprised 112 female subjects older than 45 years. Digital panoramic radiographs were taken, and patients were referred to densitometric measuring (dual energy X-ray absorptiometry) of BMD in the hip bones and lumbar spine regions (L1–L4). On the radiographs, mandibular bone density was estimated and the following indices were measured by the DIGORA^® software (Soredex, Tuusula, Finland): mental index (MI), gonial index (GI), antegonial index (AI), panoramic mandibular index (PMI) and alveolar crest resorption degree (M/M). Mandibular cortical index (MCI) was visually estimated.

Results:

Mandibular density and visual index MCI are significant predictors of hip and spine BMD. Mandibular density was marked by a significant square trend: it decreased until the age of 54 years and remained constant until the age of 64 years when it started to increase. Significant correlations were found between MI, AI and PMI values and BMD in the hip but not in the lumbar spine region. The GI and M/M values did not show statistically significant correlations with BMD of either region.

Conclusions:

Mandibular bone density and mandibular radiographic indices are useful in detecting patients with decreased BMD. The applicability of orthopantomograms in diagnosing osteoporosis/osteopenia should be recognized as the potential greatest benefit of this everyday diagnostic method in dental practice.     

Bone mineral density of the lumbar spine by dual photon absorptiometry: age-related regression in normal Japanese subjects and fracture threshold in osteoporotics

The bone mineral density (BMD) of the lumbar spine was determined by DPA in 280 normal Japanese volunteers and 11 osteoporotic women with compression fractures. In women, bone loss started from the mid thirties and accelerated after the age of 50 years at the rate of 0.75% (0.0074 g/cm2) per year. In men, bone loss started from the mid twenties and occurred linearly at the rate of 0.30% (0.0032 g/cm2). The overall diminutions in vertebral BMD throughout life in men and women were 13.0% and 24.3%, respectively. The mean vertebral BMD of the osteoporotic women with recent compression fractures was 37.5% lower than that of age-matched controls. The 90th percentile for vertebral BMD in this group was 0.584 g/cm2. By the age of 80 years, approximately one-fifth of normal Japanese women have BMD values less than this.     

Vertebral morphometry: evaluation of osteoporosis-caused fractures

PURPOSE: To compare visual reading of spine radiographs and quantitative morphometric approach for assessing the prevalence of vertebral fractures in postmenopausal osteoporosis. MATERIAL AND METHODS: In 473 postmenopausal women afferent to our Centre of Osteoporosis under-went lateral thoracic and lumbar spine radiograph to identify vertebral fractures and dual energy X-ray absorptiometry (DXA) to measure bone mineral density (BMD) of the lumbar spine (L1-L4). Osteoporosis was defined according to the World Health Organization (WHO) guidelines. To identify vertebral fractures the radiographs were visually analyzed by two radiologists; a woman was judged as fractured only if both readers independently found at least one vertebral fracture on her films. Then the spine radiographs were digitized by means of a scanner to perform quantitative vertebral morphometry (QVM) using specific software. An expert operator manually located the calipers on the vertebral bodies from T4 to L5 and the computer automatically calculated the anterior, middle and posterior vertebral heights and their ratios. A vertebral fracture was defined by morphometry as a reduction by at least 20%, with an absolute decrease of at least 4 mm, in one of three height ratios of any vertebral body compared to the corresponding reference ratio for fertile women. RESULTS: Visual reading by radiologists detected 9.5% (45/473) women with vertebral fractures and QVM detected 13.7% (65/473) with statistical significance (p < 0.001). In the 75-80 years age group the prevalence of vertebral fractures reaches the maximum value, 26.3% by visual reading and 36.8% by QVM. Among fractured women, 34 were osteoporotic by DXA; 11 women found fractured by visual reading and 21 by QVM were osteopenic women, with bone mineral densities between -1 and -2.5 SD of the T-score. CONCLUSION: This study showed that quantitative assessment of spine radiographs by vertebral morphometry is an objective method that allows to identify a larger number of vertebral fractures compared to visual inspection. This is very important not only for epidemiological studies, but also for clinical use because a previous vertebral fracture increases the risk of subsequent fractures significantly. Therefore, to improve the risk assessment of vertebral fractures for osteoporotic patients it is necessary to combine the use of QVM and BMD.     

Age-related changes in cortical and trabecular bone mineral status. A quantitative CT study in lumbar vertebrae

Purpose: To investigate the age and sex dependence of the bone mineral status of human lumbar vertebrae with special regard to differences between cortical and trabecular bone.Material and Methods: The study group comprised 125 normal Japanese healthy volunteers (54 males and 71 females), and was subdivided into adult male and female groups (subjects younger than 40 years), intermediate male and female groups (ages ranging between 41 and 64 years) and old male and female groups (subjects older than 65 years). The cortical bone mineral status was estimated using a single-energy quantitative CT (SE-QCT) technique, whereas trabecular bone mineral density (BMD) was estimated using a dual-energy (DE-QCT) technique.Results: A considerable gender difference in the age-related cortical bone status was found. There was a significant reduction of the mean values of the cortical volume and BMD in the old female group compared with those obtained in the old male group.Conclusion: The results suggest that in men, cortical and trabecular bone volume decrease very little with age. In women, cortical volume and BMD and trabecular BMD decrease with age while trabecular bone volume does not. The study showed that all variables had higher values in men than in women and that the difference increased with age.     

Determination of bone mineral density in the third lumbar vertebral body using photon absorptiometry techniques

Dual-photon absorptiometry and triple-energy X-ray absorptiometry were used to investigate the total bone mineral content and density as well as the trabecular bone mineral density in the third lumbar vertebral body. Both anteroposterior (AP) and lateral (LAT) measurements were performed. By combining the two projections it was found that the mean trabecular bone mineral density for all 202 subjects included in the study was 52% (SD±20%) of the total bone mineral density in the third lumbar vertebral body. The mean trabecular bone mineral density as a fraction of the total vertebral body bone mineral density decreased as a function of age. The relative annual change in this fraction differed between males and females. It was also found that neither trabecular nor total bone mineral density differed significantly between male and female subjects aged 25–35 years, and bone mineral density (BMD), expressed in g/cm³, showed no correlation to subject height, body weight or body mass index (BMI). Male and female individuals showed different rates of change of trabecular bone mineral density with age.     

Risk of vertebral osteoporosis in post-menopausal women with alterations of the mandible

BACKGROUND: Previous studies have suggested that a thin or eroded cortex of the mandible detected on dental panoramic radiographs is associated with low vertebral bone mineral density (BMD) or osteoporosis. However, those studies did not estimate the multivariate-adjusted risk for low vertebral BMD or osteoporosis associated with alterations of the mandible. METHODS: BMD of the lumbar vertebrae (L2-L4) was compared among quartiles of cortical width and among three cortical shape categories in 450 post-menopausal women (mean age, 57.2 years), adjusted for potential confounders. The odds ratios for low BMD or osteoporosis according to cortical width and shape were also calculated. RESULTS: Significant associations were found between cortical width and shape, and vertebral BMD. The odds ratios for low vertebral BMD associated with the second, third and lowermost quartiles of cortical width were 1.71 (95% confidence interval (CI), 0.96-3.05), 2.30 (95% CI, 1.29-4.11) and 5.43 (95% CI, 2.16-10.71), respectively, compared with the uppermost quartile. The odds ratios for osteoporosis according to cortical width category were similar to those for low BMD. The odds ratios for low BMD associated with mildly to moderately and severely eroded cortices were 3.85 (95% CI, 2.37-6.25) and 7.84 (95% CI, 2.57-23.90), respectively, compared with normal cortex. The odds ratios for osteoporosis associated with mildly to moderately and severely eroded cortices were 4.73 (95% CI, 2.54-8.80) and 14.73 (95% CI, 6.14-35.47), respectively. CONCLUSIONS: Post-menopausal women with alterations of the mandible may have an increased risk for low vertebral BMD or osteoporosis.     

Dual-energy X-ray absorptiometry of the vertebrae: determining which vertebrae should be scanned]

This study was aimed at verifying whether bone mineral density (BMD) and its loss with aging are different in the lumbar vertebrae and whether the region of interest--which is usually limited to the L2-L4 segment--may be extended to L1-L4. BMD was measured by means of dual-energy X-ray absorptiometry (Hologic QDR 1000) in 74 women, aged 37 to 78 years, not affected with any disease or subjected to any treatment known to interfere with bone metabolism. The relationship between age and BMD was expressed by the following equations for L1, L2, L3: BMD-L1 = 1181.68-7.85 x age, BDM-L2 = 1251.57-7.70 x age, BMD-L3 = 1231.66-6.57 x age, as shown by linear regression analysis. The behavior of the bone density of L4 with age appeared to be different and could not be described by linear regression curves and was therefore not comparable with that of the other vertebrae. BMD was different in the four lumbar vertebrae as shown by: a) the diversity of the intercept of the regression lines describing age-bone density relationships (F = 7.7, p < 0.001); b) the bone density of L1 being lower than the mean bone density of the L2-L4 region (p < 0.005); c) the bone density of L4 being higher than the mean bone density of the L1-L3 region (p < 0.001). In order to evaluate the effect of senile degenerative changes of the vertebrae on the relevant bone density, two groups of women were considered, according to age--i.e., pre- or iuxtamenopausal and late postmenopausal. It appeared that the BMD of L1 was always more correlated to the bone density of L2 and L3 than the BMD of L4. Our results suggest that L1 is homogeneous to the L2-L3 region, relative to both bone density and its loss with aging. Therefore, L1 should be included in the region of interest during the examination. Even though the bone mineral content of L4 and its loss with aging seem to be different, our results do not allow the exclusion of L4 from the scanned area.     

Influence of anthropometric parameters and bone size on bone mineral density using volumetric quantitative computed tomography and dual X-ray absorptiometry at the hip

PURPOSE: To evaluate the influence of anthropometric parameters (age, height, and weight) and bone size on bone mineral density (BMD) using volumetric quantitative computed tomography (QCT) and dual X-ray absorptiometry (DXA) in a group of elderly women. MATERIAL AND METHODS: BMD values were obtained with DXA and QCT at the spine and hip in a cohort of 84 elderly women (mean age 73 +/- 6 years). QCT measures included trabecular, integral, and cortical BMD assessed at the hip and spine as well as cross-sectional areas of the mid-vertebrae and proximal femora. Spinal integral and femoral neck BMD measures were well matched to the regions of bone quantified on anteroposterior (AP) spine DXA and the femoral neck region of hip DXA. RESULTS: When QCT parameters were linearly regressed against body height and weight, only the relationships with weight were found to be statistically significant. Except for cortical BMD at the femoral neck, all BMD and geometric parameters measured from both DXA and QCT showed statistically significant associations with body weight (r2 = 0.4, 0.0001 < P < 0.02). The strongest associations with weight were found for DXA Neck (DXA_NECK) and DXA lumbar spine (DXA_LSP) (r2 = 0.4, P < 0.0001). CONCLUSION: The relationship of DXA BMD is stronger than QCT BMD with body weight and it encompasses the response of both bone size and density to increasing body mass.     

Quantitative ultrasound of the phalanges and DXA of the lumbar spine and proximal femur in evaluating the risk of osteoporotic vertebral fracture in postmenopausal women

Purpose

This study was undertaken to compare the quantitative ultrasound (QUS) parameters of amplitudedependent speed of sound (AD-SoS) and ultrasound bone profile index (UBPI) of the phalanges with bone mineral density (BMD) of the lumbar spine and proximal hip using dual-energy X-ray absorptiometry (DXA) in discriminating women with vertebral fracture.

Materials and methods

A total of 692 postmenopausal Caucasian women were included in the study. The presence of vertebral fracture was evaluated by radiography. AD-SoS and UBPI were measured at the phalangeal metaphysis using a DBM Sonic device. Multiple logistic regression analysis was performed to estimate the odds ratio (OR) for vertebral fractures. The ORs were also adjusted for the significant anthropometric variables of age, weight and height. Furthermore, for QUS parameters, the ORs were also adjusted for lumbar spine and total hip BMD.

Results

All measurements obtained with DXA and QUS significantly discriminated between women with and without fractures (p<0.0001). However, the OR was higher for lumbar spine BMD (OR 4.01), AD-SoS (OR 3.81), total hip (OR 3.7) and femoral neck BMD (OR 3.62).

Conclusions

The QUS parameter AD-SoS showed diagnostic sensitivity equal to that of lumbar DXA in discriminating between women with and without osteoporotic vertebral fractures.     

Lumbar and radial bone mineral density in children and adolescents with X-linked hypophosphatemia: evaluation with dual X-ray absorptiometry

Objective. To evaluate the bone mineral status of children being treated for X-linked hypophosphatemia, including potential differences between cortical bone in the radial diaphysis and combined cortical and trabecular bone in the lumbar spine. Design and patients. Forty-four bone mineral evaluations were performed in 11 children and adolescents with X-linked hypophosphatemia. Bone mineral density (BMD) of the lumbar spine and the radial diaphysis were measured by dual X-ray absorptiometry (DXA), second metacarpal cortical thickness was measured on hand radiographs, and these results were expressed as Z-scores (standard deviations from the mean). Results. For the 11 initial examinations, Z-scores (mean±SD) were: radial BMD, –2.73±1.15, lumbar BMD, +1.28±1.53; and cortical thickness, –2.21±0.95. Lumbar BMD Z-scores were significantly greater than those for radial BMD and cortical thickness. On follow-up examinations there was a mild increase in radial BMD and decrease in lumbar BMD. Although these changes were statistically significant, they were quite small and the discordance between radial and lumbar BMD was not corrected. Conclusions. Children and adolescents who are being treated for X-linked hypophosphatemia manifest a bone mineral disorder characterized by decreased BMD in the appendicular skeleton and increased BMD in the lumbar spine. Although current therapy is successful in its anti-rachitic effects, it does not correct this bone mineral disorder and additional therapeutic trials should be considered. Received: 28 May 1999 Revision requested: 22 July 1999 Revision received: 18 October 1999 Accepted: 26 October 1999     

Measurement of bone mineral content and bone density in healthy twelve-year-old white females.

Bone mineral content (BMC) and bone mineral density (BMD) measurements were made by dual-energy x-ray absorptiometry (DEXA) in 112 healthy 12-yr-old white girls for the purposes of: (1) establishing reference data on total-body mineral content of 12-yr-old girls and (2) comparing the lumbar spinal bone density values from a dedicated scan with the lumbar region of interest bone density values from a whole-body scan. Total BMC ranged from 799 g to 2083 g with mean and median values of 1276 g and 1218 g. Total-body bone density ranged from 0.75 to 1.03 g/cm2 with mean and median values of 0.88 and 0.87 g/cm2. The mean and median lumbar bone density values from the lumbar scan mode were 0.74 and 0.73 g/cm2 and were not significantly different from the mean and median lumbar bone density values of 0.71 and 0.70 g/cm2 obtained from the region of interest data from the total-body scan. These results establish baseline bone mass and bone density values for our longitudinal study of bone accretion in young women and validate the use of lumbar vertebral bone density values obtained from whole-body scans.     

Vertebral bone mineral measurement using dual photon absorptiometry and computed tomography

The lumbar spine of 14 cadavers was studied both by 153Gd dual photon absorptiometry (DPA) and quantitative computed tomography (QCT) at 96 and 125 kVp. The intact spine and the individual vertebrae were analyzed. After these measurements the ash content of the vertebral body, the posterior elements, and the transverse processes was determined. The fat content of the vertebral body as well as its volume was also measured. With DPA, the bone mineral content (BMC) determined in situ as well as on excised spine specimens correlated highly with the amount of total vertebral ash (r greater than 0.92, SEE less than 3.2 g). The bone mineral density (BMD, area density) of 3 lumbar vertebrae correlated accurately with the mean ash density of the vertebral body (r greater than 0.81, SEE less than 0.015 g/cm3). The so-called corpus density and central density determinations were less accurate. No difference in accuracy was found between measurements when using 3 mm and 4.5 mm step intervals. Variations in the distribution of mineral between the vertebral body and the posterior elements contribute to the error in predicting vertebral body mineral with DPA. QCT gave a smaller error when a cylindric portion of the vertebral body with a 20 mm diameter was measured compared with one with a 9 mm diameter, when the dual energy technique was used (p less than 0.01). With dual energy QCT a correlation was found between a center segment of 3 vertebrae in the lumbar spine and the mean ash density of the vertebral body of r = 0.92 (SEE = 0.010 g/cm3).(ABSTRACT TRUNCATED AT 250 WORDS)     

Comparison of ultrasound transmission velocity with computed metacarpal radiogrammetry and dual-photon absorptiometry

The aim of our study was to evaluate the validity of a quantitative US technique for measuring the bone density of the proximal phalanges of the nondominant hand compared with computed metacarpal radiogrammetry and dual-photon absorptiometry (DPA) of the lumbar spine. Mean US bone velocity (UBV) correlated with mean metacarpal cortical index (MCI), with mean metacarpal bone density (MBD) and with bone mineral density (BMD) of the lumbar spine, whereas it was correlated negatively with age and menopause duration. The average UBV was significantly higher in premenopausal women than in postmenopausal women, and higher in normal lumbar DPA patients than in reduced lumbar DPA patients. We conclude that the US evaluation of the nondominant hand proximal phalanges may be a new alternative way for measuring bone mass in screening of osteoporosis. Correspondence to: A. Sili Scavalli     

Computerized analysis of gray-value profiles in spongy and cortical bone. Clinical experience.

RATIONALE AND OBJECTIVES: Osteoporosis is characterized by a loss of bone mineral density and deterioration of structure. The authors present a structural parameter for the quantitative assessment of osteoporotic changes in vertebral bone. METHODS: In 40 patients without or with known osteoporotic fractures, spongiosa and cortical bone mineral density was measured in lumbar vertebrae 1 to 3 by quantitative CT. Additional axial high-resolution CT slices were obtained for the structural analysis. In the spongiosa, the gray-value profile along a horizontal line in the CT slice was used, whereas in the cortical shell a profile was obtained from the cortical ridge. Both profiles were intersected with a horizontal line of variable position, and the maximum number of intersections was determined. RESULTS: The maximum number of intersections is significantly higher in cases with fractures (spongiosa 48.6, cortical shell 77.3) than in cases without fractures (spongiosa 42.1, cortical shell 62.4). It also correlates with bone mineral density and age. CONCLUSIONS: The presented method shows significantly different numeric results for patients with and without osteoporotic fractures. The analysis is easy to perform and provides additional information on the bone structure that may be used in combination with bone mineral density measurements.     

Relationships of cervical, thoracic, and lumbar bone mineral density by quantitative CT

PURPOSE: The purpose of this work was to compare, using quantitative CT (QCT), vertebral bone mineral density (BMD) in the cervical, thoracic, and lumbar spine in healthy volunteers. METHOD: QCT of the vertebral bodies of C2, C5, T12, and L4 was performed on 50 healthy volunteers (25 women, 25 men; mean age 31.7 years). Trabecular BMD analysis was performed at each level. RESULTS: Mean BMDs (mg/cm3 calcium hydroxyapatite) for women and men were highest at C5 (BMD women/men 341.6/300.6 mg/cm3) and C2 (297.2/269.6 mg/cm3) and lowest at T12 (193.1/184.9 mg/cm3) and L4 (186.2/180.1 mg/cm3). The BMD of C2 was statistically significantly different from that of C5, T12, and L4 (p < 0.0001) for both genders. Also, the BMD of C5 differed significantly from that of T12 and L4 (p < 0.0001). The BMD of C5 showed significant gender differences (p = 0.002). Correlation coefficient showed a strong correlation between the BMD of T12 and L4 for both genders (women, r = 0.67; men, r = 0.90). CONCLUSION: Trabecular BMD of C2 and C5 measured by QCT is significantly higher than trabecular BMD of T12 and L4 in nonosteoporotic volunteers of both genders.     

CT evaluation of trabecular and cortical bone mineral density of the lumbar spine in patients on hemodialysis

It is difficult to evaluate the severity of bone involvement in patients on maintenance hemodialysis (HD) by the measurement of vertebral bone mineral density (BMD), since many endocrine factors influence bone metabolism, making the value of BMD variable from high to low. It is also difficult to interpret the BMD measured in one ROI (region of interest) since bone density distribution is sometimes very heterogenous. On the other hand QCT method is useful to evaluate the value of trabecular and cortical bone mineral density separately. Vertebral BMD was measured in 138 patients on maintenance HD, by using DEQCT (dual energy QCT). 161 patients without bone metabolic disorders were studied for control group. In patients on HD, various BMD values ranging from high to low were observed, and there was no correlation between BMD value and duration of HD. The number of patients with low mineral content was greater than that with high mineral content in both cortical and trabecular bone. The trabecular BMD decreased with age, and the speed of BMD decline was the same in both sexes. The rapid decrease of trabecular BMD after menopause seen in control female group was not observed in female patients on hemodialysis. The deviation of BMD from the age-matched average BMD value was smaller in older male patients than that in young male and female patients. In order to evaluate the difference of change between the trabecular and cortical bone at the same vertebra, cases in which discrepancy of Z-score was more than 0.2 were divided into three groups; group A: increased trabecular BMD (Z-score greater than 1), group B: decreased trabecular BMD (-1 greater than Z-score), group C: normal trabecular BMD (-1 less than Z-score less than 1), and in each group T/C ratio (Z-score of trabecular BMD/Z-score of cortical BMD ratio) was evaluated. In group A, almost all cases showed trabecular BMD to be higher than cortical, and in group B, 60% cases showed trabecular BMD to be lower than cortical, suggesting that the change of BMD in trabecular bone is greater than that in cortical bone.     

The effect of region of interest selection on dual energy X-ray absorptiometry measurements of the calcaneus in 55 post-menopausal women

Bone mineral density (BMD) of the calcaneus was assessed by dual energy X-ray absorptiometry (DXA) in four different regions of the calcaneus in 20 pre-menopausal and 55 post-menopausal women, none of whom were on treatment or suffering from conditions affecting bone. The total body option in the small animal software package of a Lunar DPX-L bone densitometer was used. The precision of the technique (%CV) varied from 0.7 to 2.2% depending on the region scanned. For post-menopausal women, BMD results in the mid and posterior parts of the calcaneus varied by < 7% while BMD in the anterior region was about 20% lower. DXA of the calcaneus was compared with measurements at the spine (L2-L4) and hip (femoral neck) and changes with age were estimated from cross-sectional data. BMD of the calcaneus was significantly reduced in 28 post-menopausal women with low lumbar spine BMD (-2SD) compared with women with normal spine BMD. Calcaneal BMD was significantly correlated to axial BMD (r = 0.45-0.77) and to age (r = 0.45 to -0.63). For a subgroup of 33 post-menopausal women measured twice after approximately 1 year, calcaneus BMD decreased by between 1.2% and 2.5% while axial BMD showed no significant change. Unlike spine or femoral neck BMD, the decrease in calcaneus BMD was significantly greater in women with low spine BMD than in normal women, possibly indicating improved detection of skeletal changes. The optimum measurement sites for BMD in the calcaneus were within the mid or posterior part of the calcaneus or enclosing the whole posterior calcaneus. The calcaneus was shown to be a precise, sensitive and simple measurement site suitable for the assessment of osteoporosis, especially in the elderly where degenerative changes in the spine and hip can complicate BMD assessment.     

绝经后妇女腰椎骨密度测量的研究

作者对患有或未患腰椎骨折的绝经后妇女的骨密度测量进行了研究分析，旨在比较L－DXA和mL－DXA对骨折诊断的敏感性。材料和方法：共240例绝经后妇女。根据各胸腰椎（胸4至腰4）倒位X线平片所见，并采用目视半定量法判断椎体的骨折或其程度，腰椎骨密度值分别选用L－DXA和mL－DXA所测数据。结果：骨折组的年龄高于非骨折组，而其BMD值则低于非骨折组。分析比较L－DXA和mL—DXA的结果表明其下降百分数和Z分数相似，ROC曲线下面积也无显著性差异，logistic回归分析中，两者年龄调整后的优势比无显著性差异。进一步将正常与轻度骨折组比较，两者的ROC面积仍无显著性差异。结论：在区分正常与骨折以及正常与轻度骨折时，mL－DXA并不优于L－DXA。因轻度骨折的L－DXA和mL－DXA所测骨密度值均低于非骨折组，故应视其为骨折。     

Quantitative computed tomography

Quantitative computed tomography (QCT) is an established technique for measuring bone mineral density (BMD) in the axial spine and peripheral skeleton (forearm, tibia). QCT can determine in three dimensions the true volumetric density (mg/cm 3) of trabecular or cortical bone at any skeletal site. However, because of the high responsiveness of spinal trabecular bone and its importance for vertebral strength, QCT has been principally employed to determine trabecular BMD in the vertebral body. QCT has been used for assessment of vertebral fracture risk, measurement of age-related bone loss, and follow-up of osteoporosis and other metabolic bone diseases. This article reviews the current capabilities of QCT at different skeletal sites and the recent technical developments, including volumetric acquisition.     

老年男性腰椎的QCT骨密度测量

目的:探讨老年男性腰椎定量CT(QCT)骨密度(BMD)测量的价值及其应用中的注意事项。方法:对516例老年男性进行腰椎体松质骨的QCT骨密度测量。检查时通过L_(1～5)椎体中心和腰椎体模中心行轴位扫描。然后对各椎体及体模图像进行测量。所得数据由腰椎骨密度分析软件分析处理,得出个体腰椎的平均骨密度值及T-Score值、Z-Score值,再将其结果与正常人群的骨密度峰值进行比较,经分析得出诊断结论。诊断标准参照WHO的标准及国内推荐的标准执行。结果:516例中骨密度正常者24例,占4.7%;骨密度降低者109例,占21.1%;骨质疏松症者318例,占61.6%;严重骨质疏松症者65例,占12.6%。结论:腰椎体松质骨的QCT骨密度测量可较早地反映出老年男性体内骨矿含量的变化,对早期发现和确诊老年男性的骨质疏松症具有十分重要的价值。在QCT检查中,需高度重视测量质量的控制。