容积性定量CT测量股骨近端骨密度准确性研究

目的通过分别对比容积性定量CT(vQCT)、双能X射线吸收法(DXA)与灰化法测量股骨近端骨密度结果,确定并对比相关性,进行指导临床骨质疏松诊断及治疗。方法选取20个尸体股骨近端标本,先使用DXA骨密度仪扫描,测得骨矿含量(BMC)及骨密度(BMD)。再对标本相同部位行64层螺旋CT扫描,数据导入OsteoCAD软件自动分析得出骨密度值。应用灰化法得出标本灰质量密度。所有资料进行统计分析分别确定并对比vQCT及DXA测量的骨密度值与灰密度之间的相关性。结果vQCT测量股骨颈骨密度与灰质量密度线性相关性较好(r=0.852,P0.01),DXA与灰质量密度的相关性略差(r=0.807,P0.01)。结论vQCT测得的骨密度较DXA与灰质量密度线性相关性更好,可靠性高,对于诊断骨质疏松,预测骨质疏松性骨折,评价、指导骨质疏松骨折手术更有应用价值。     

单能X线和定量CT测量骨密度的相关性研究

目的：比较跟骨单能X线（SXA）测定值和腰椎定量CT（QCT）测定值的相关性,旨在为临床上合理地应用跟骨SXA测定仪。方法：应用单能X线和定量CT骨密度测定仪测量了201例正常或病人的跟骨及椎体骨密度,对测量结果进性了统计学相关性分析。结果：男女人群SXA和QCT的总相关系数分别为0．653和0．638;P＜0．001,骨质疏松组SXA与QCT的测定值有非常显的相关性（P＜0．001）,骨量正常组和骨量减少组则无显的相关性（P＞0．05）,从年龄上40岁以上女性与60岁以上男性SXA与QCT的测定值有非常显的相关性。结论：SXA测定不能代替QCT测定,但SXA机型小,轻便且价廉,尤其在40岁以上的女性和在60岁以上的老年男性,以及患有面骨质疏松的病人,他们的测量结果与QCT有着显的相关性,故在临床上不失为诊断绝经后妇女和老年性骨质疏松的一种手段。     

两种QCT骨密度测量软件检测腰椎骨密度的比较

目的 探讨飞利浦工作站IntelliSpace (IP) （无体模）和Mindways (MW) QCT Pro（有体模）两种骨密度测量软件测量腰椎BMD值的重复性、相关性、一致性及其在临床中的应用价值。方法 临床需要进行腹部扫描患者222例,将扫描数据分别传到IP和MW骨密度测量软件进行测量,应用 Pearson 相关性检验分析两种软件测量结果的相关性,应用配对样本 t 检验分析两种方法测量结果平均值是否有差异,应用Bland-Altman 图分析二者的一致性。自222例数据中随机抽取30例,由 2 名测量者在不同时间分别在各自软件上测量2 次椎体BMD 值,评价两个软件测量重复性。结果 重复性研究：IP及MW 对于所选 30 例 2 次测量结果之间均具有显著相关性(r=0.977,P＜0.01) 。2次测量结果之间差异均无统计学意义 (P>0.05) 。IP测量BMD值（92.93±36.16 mg/cm3）显著低于MW测量BMD值（112.78±41.36 mg/ cm3）,但两者测量值之间成正相关（r=0.911,P＜0.01）,对原始数据进行Bland-Altman 分析,差值大部分位于差值平均值±1. 96 标准差范围内,提示两种测量一致性好。结论 IP骨密度测量软件不能直接采用QCT诊断标准,但其与MW骨密度测量软件的一致性及相关性好,可用于对临床患者骨密度的评价及随访。     

绝经妇女腰椎及髋关节定量cT骨密度测量诊断骨质疏松的初步研究

目的比较绝经后妇女L2-L4椎体及髋关节两个部位的定量CT骨密度（BMD )测量诊断骨 质疏松的效能。方法175例绝经妇女,年龄48-96岁,平均年龄为69 ±9岁。同时QCT测量L2-L4椎体的平均体积骨密度及髋关节类DXA的面积骨密度,右股骨颈和全髋二个感兴趣区（ROI )。 采用国际临床骨密度学会（ISCD )QCT骨质疏松诊断标准（<80 mg/cm3 )和WHO髋关节DXA骨密 度诊断标准即股骨颈或全髋感兴趣区的T值（-2.5 SD )进行骨质疏松诊断。比较二者诊断骨质疏 松的效能。结果175绝经后妇女中,QCT骨密度测量腰椎部位骨密度值骨质疏松的检出率是44%( 77/175 )。如果采用髋部检查股骨颈部位为11%.( 19/175 ),全髋部位为14%.( 24/175 ),或二者任一 部位为18%_( 31/175 )。如果只做腰椎,不做髋关节,有7人漏诊,而如果只做髋关节,不做腰椎会漏 诊44人。结论采用QCT骨密度测量,绝经妇女腰椎检查骨质疏松检出率为44%_,而髋部检查检出 率为18%_。采用QCT骨密度测量,测量腰椎一个部位就可以诊断骨质疏松。     

中老年人椎体骨密度定量CT测定研究

目的探讨定量CT（quantitative CT,QCT）椎体骨密度（bone mineral density,BMD）测定在诊断骨质疏松症中的临床价值,分析骨质疏松发生率与年龄、性别的关系。方法对597例中老年无症状体检者进行BMD测定,其中男性356例,女性241例,年龄30～89岁,按年龄、性别分组,每10岁为一年龄段。将QCT扫描线分别定位于L1～4椎体中间层面,与椎体上下缘平行扫描。结果中老年人BMD随年龄增高而下降,本组骨质疏松症发生率,女性：50～59岁为54.05%,60～69岁为81.81%,70～79岁为94.74%,80～89岁为100%;男性：50～59岁为25%,60～69岁为50%,70～79岁为64.52%,80～89岁为90.91%。结论 QCT诊断骨质疏松症敏感、准确、重复性强,易于推广应用。骨质疏松症发生率与年龄增加有关,年龄越大,骨质疏松症发生率越高,女性显著高于男性。     

腰椎定量CT与双能X线骨密度测量对老年男性骨质疏松的诊断效能比较

目的评估腰椎定量悦栽与双能X线骨密度测量诊断老年男性骨质疏松的效能。方法 连续选取2012年2月至2012年8月期间于北京积水潭医院干部科住院的老年男性患者,共59例,年 龄54耀92岁。本组病例均行腰椎正位和髋关节DXA及腰椎QCT检查,且两项检查间隔时间不超过 1个月。结果采用世界卫生组织（WHO )DXA -2. 5SD和国际临床骨密度学会（ISCD )腰椎QCT < 80 mg/cm3的骨质疏松诊断标准,DXA诊断本组病例腰椎、髋关节及腰椎或髋关节任一部位骨质疏松 的检出率分别为0%_、. 5豫和8. 5豫。腰椎QCT诊断本组病例骨质疏松的检出率为35. 6豫。其中腰 椎QCT诊断为骨质疏松而腰椎正位DXA未诊断者21例,占35. 6豫,其中3例CT显示有骨质疏松性 椎体骨折;腰椎QCT诊断为骨质疏松而髋关节DXA或任一部位DXA未诊断者均为16例,占 27. 1豫。结论 腰椎QCT比髋关节DXA及腰椎正位DXA对老年男性骨质疏松的诊断更敏感。腰 椎QCT骨密度测量对老年男性的骨质疏松诊断具有较高的临床价值。     

能量CT定量测量骨密度和骨髓脂肪的研究现状

一直以来，骨质疏松症都是一个主要的公共卫生疾病，有着很高的致残率和死亡率，严重影响着患者的生命健康和生活质量，也导致国家医疗卫生系统承担着高昂的医疗保健费用。目前，骨密度是诊断骨质疏松症和预测骨折风险的主要指标。因此，精确测量骨密度对骨质疏松的早期预防至关重要，但是影响骨密度精确测量的因素有很多，骨髓脂肪便是现在关注的一个重点。目前，定量分析骨髓脂肪含量和骨密度的手段在不断革新，而能量CT作为一个新型技术备受研究者们的关注。因此，本综述旨在探讨能量CT定量分析骨密度和骨髓脂肪含量的研究进展，以期为后续相关研究提供一个新的可行性影像方法。     

定量CT腰椎骨密度测量的低剂量研究

目的通过临床验证多排螺旋定量悦栽腰椎低剂量扫描参数,制定最佳的低剂量多排螺旋 QCT腰椎扫描协议。资料与方法选取住院拟进行腰椎手术,术前行常规多排螺旋悦栽平扫和腰椎 匝悦栽检查的30位患者。其中男：0例,女20例;年龄48耀79岁,平均年龄63.97依8.66岁。分两次 采集常规250皂粤和50皂粤两组腰椎加校准体模QCT容积数据,将两组L2-L4容积数据传至骨密度 工作站进行骨密度（Bone Mineral DensiLy )测量。应用统计软件杂孕杂杂15. 0进行统计分析。结果250 皂粤组与50皂粤组L2、L3、蕴4平均BMD值无差异（孕>0. 05 )两组三椎体总平均BMD值无差异（责跃 0. 05 )250 mA 组辐射剂量 DLP 值为 229. 06 土 12. 35 mGy cm。0 mA 组 DLP 值为 45. 78 ±2. 48 mGy 糟皂。结论多排螺旋定量QCT腰椎低剂量扫描技术能够保证BMD测量准确性,同时使患者的受辐射 剂量比常规多排螺旋CT腰椎扫描大幅度降低     

定量超声和双能X线骨密度测定诊断骨质疏松的比较

目的通过对同一个人的跟骨超声强度（STI）测量与双能X线吸收法（DEXA）测量腰2-4、股骨近端骨密度（BMD）的临床对比,评价定量超声骨质测量仪（QUS）跟骨STI的测量,对诊断骨质疏松（OP）的敏感性和与DEXA测量BMD的相关性.方法对3266名20～89岁健康人群同时采用DEXA测量L2-4、右股骨近端（Neck、Ward、Troch）BMD和QUS测量右跟骨STI值进行相关分析.结果峰值骨量男性STI与BMD均出现在20～29岁,女性STI出现在20～29岁,BMD则出现在30～39岁;随年龄的增加腰椎、股骨近端BMD及超声强度均下降,女性在50岁后,男性在70岁后有个显著下降过程;OP检出率两种仪器无明显差异.在健康人中BMD与STI的相关系数（R=0.21-0.26）,骨质疏松患者BMD与STI的相关系数（R=0.14-0.24）.结论DEXA测量的BMD与QUS测量的STI无相关关系.这表明QUS主要测量骨的结构,而DEXA则是测量骨量的变化,两者相辅相承,共同测量能更好地监测骨质疏松、预测OP性骨折的发生.     

双能X线吸收法骨密度测定

骨质疏松作为老年人的常见病之一 ,越来越受到社会各界的关注。骨密度测量是明确骨质疏松的诊断、估计骨质疏松的程度、评价骨质疏松的疗效[1 ] 的必要手段。随着骨密度测量技术的发展 ,越来越多的精确度和准确度越来越高的骨密度测量方法问世。双能Ｘ线吸收法 (ＤＸＡ)以其准确度和精确度高、辐射剂量低、扫描时间短、调节稳定等优点广泛地应用于临床[2 ] 。本文就ＤＸＡ测定方法有关内容进行综述 ,供广大临床工作者参考。ＤＸＡ的工作原理ＤＸＡ用Ｘ线管代替同位素产生独立的双能量光子 ,通过单独测量这两种能量光子的吸收情况 ,计算出骨…     

Thoracic bone mineral density measured by quantitative computed tomography in patients undergoing spine surgery

BACKGROUND CONTEXTThe thoracic spine is a common location for vertebral fractures as well as instrumentation failure after long spinal fusion procedures. The association between those complications and bone mineral density (BMD) are well recognized. Due to the overlying sternum and ribs in the thoracic spine, projectional BMD assessment tools such as dual energy x-ray absorptiometry (DXA) are limited to the lumbar spine. Quantitative computed tomography circumvents several shortcomings of DXA and allows for level-specific BMD measurements. Studies comprehensively quantifying BMD of the entire thoracic spine in patients undergoing spine surgery are limited.PURPOSEThe objective of this study was: (1) to assess the reliability of thoracic QCT measurements, (2) to determine possible level-specific BMD variation throughout the thoracic spine and (3) to assess the correlation between BMDs of the T1-T12 spinal levels.STUDY DESIGN/SETTINGCross-sectional observation study.PATIENT SAMPLEPatients undergoing spine surgery from 2016–2020 at a single, academic institution with available preoperative CT imaging of the thoracic spine were included in this study.OUTCOME MEASURESThe outcome measure was BMD measured by QCT.METHODSPatients undergoing spine surgery from 2016–2020 at a single, academic institution with available preoperative CT imaging of the thoracic spine were included in this study. Subjects with previous instrumentation at any thoracic level, concurrent vertebral fractures, a Cobb angle of more than 20 degrees, or incomplete thoracic spine CT imaging were excluded. Asynchronous quantitative computed tomography (QCT) measurements of T1-T12 were performed. To assess inter- and intra-observer reliability, a validation study was performed on 120 vertebrae in 10 randomly selected patients. The interclass correlation coefficient (ICC) was calculated. A pairwise comparison of BMD was conducted and correlations between each thoracic level were evaluated. The statistical significance level was set at p<.05.RESULTS60 patients (men, 51.7%) met inclusion criteria. The study population was 90% Caucasian with a mean age of 62.2 years and a mean BMI of 30.2 kg/m². The inter- and intra-observer reliability of the thoracic QCT measurements was excellent (ICC of 0.97 and 0.97, respectively). The trabecular BMD was highest in the upper thoracic spine and decreased in the caudal direction (T1 = 182.3 mg/cm³, T2 = 168.1 mg/cm³, T3 = 163.5 mg/cm³, T4 = 164.7 mg/cm³, T5 = 161.4 mg/cm³, T6 = 152.5 mg/cm³, T7 = 143.5 mg/cm³, T8 = 141.3 mg/cm³, T9 = 143.5 mg/cm³, T10 = 145.1 mg/cm³, T11 = 145.3 mg/cm³, T12 = 133.6 mg/cm³). The BMD of all thoracic levels cranial to T6 was statistically higher than the BMD of all levels caudal to T6 (p < .001). Nonetheless, significant correlations in BMD among all measured thoracic levels were observed, with a Pearson's correlation coefficient ranging from 0.74 to 0.97.CONCLUSIONSThere is significant regional BMD variation in the thoracic spine depending on spinal level. This BMD variation might contribute to several clinically relevant phenomena. First, vertebral fractures occur most commonly at the thoracolumbar junction including T12. In addition to mechanical reasons, these fractures might be partially attributed to thoracic BMD that is lowest at T12. Second, the optimal upper instrumented vertebra (UIV) for stopping long fusions to the sacrum and pelvis is controversial. The BMD of surgically relevant upper thoracic stopping points (T2-T4) was significantly higher than the BMD of lower thoracic stopping points (T10-T12). Besides stress concentration at the relatively mobile lower thoracic segments, the low BMD at these levels might contribute to previously suggested higher rates of junctional failures with short fusions.     

Regional bone mineral density differences measured by quantitative computed tomography in patients undergoing anterior cervical spine surgery

BACKGROUND CONTEXTClinically, the association between bone mineral density (BMD) and surgical instrumentation efficacy is well recognized. Although several studies have quantified the BMD of the human lumbar spine, comprehensive BMD data for the cervical spine is limited. The few available studies included young and healthy patient samples, which may not represent the typical cervical fusion patient. Currently no large scale study provides detailed BMD information of the cervical and first thoracic vertebrae in patients undergoing anterior cervical spine surgery.PURPOSEThe objective of this study was to determine possible trabecular BMD variations throughout the cervical spine and first thoracic vertebra in patients undergoing anterior cervical discectomy and fusion (ACDF) and to assess the correlation between BMDs of the spinal levels C1–T1.STUDY DESIGN/SETTINGThis is a retrospective case series.PATIENT SAMPLEPatients undergoing ACDF from 2015 to 2018 at a single, academic institution with available preoperative CT imaging were included in this study.OUTCOME MEASURESThe outcome measure was BMD measured by QCT.METHODSPatients that underwent ACDF from 2015 to 2018 at a single, academic institution were included in this study. Subjects with previous cervical instrumentation or missing/incomplete preoperative cervical spine CT imaging were excluded. Asynchronous quantitative computed tomography (QCT) measurements of the lateral masses of C1 and the C2-T1 vertebral bodies were performed. For this purpose, an elliptical region of interest that consisted exclusively of trabecular bone was selected. Any apparent sclerotic levels that might affect trabecular QCT measurements were excluded from the final analysis. Interobserver reliability of measurements was assessed by calculating the interclass correlation coefficients (ICC). Pairwise comparison of BMD was performed and correlations between the various cervical levels were evaluated. The statistical significance level was set at p<.05.RESULTSIn all, 194 patients (men, 62.9%) met inclusion criteria. The patient population was 91.2% Caucasian with a mean age of 55.9 years and mean BMI of 28.2 kg/m². The ICC of cervical QCT measurements was excellent (ICC 0.92). The trabecular BMD was highest in the mid-cervical spine (C4) and decreased in the caudal direction (C1 average=253.3 mg/cm³, C2=276.6 mg/cm³, C3=272.2 mg/cm³, C4=283.5 mg/cm³, C5=265.1 mg/cm³, C6=235.3 mg/cm³, C7=216.8 mg/cm³, T1=184.4 mg/cm³). The BMD of C7 and T1 was significantly lower than those of all other levels. Nonetheless, significant correlations in BMD among all measured levels were observed, with a Pearson's correlation coefficient ranging from 0.507 to 0.885.CONCLUSIONSTo the authors’ knowledge this is the largest study assessing trabecular BMD of the entire cervical spine and first thoracic vertebra by QCT. The patient sample consisted of patients undergoing ACDF, which adds to the clinical relevance of the findings. Knowledge of BMD variation in the cervical spine might be useful to surgeons utilizing anterior cervical spine plate and screw systems. Due to the significant variation in cervical BMD, procedures involving instrumentation at lower density caudal levels might potentially benefit from a modification in instrumentation or surgical technique to achieve results similar to more cephalad levels.     

Quantification of bone mineral measured by single-energy computed tomography

Twenty cadaver femoral condyles were examined with single-energy quantitated computed tomography (QCT), and the composition of the bone scanned was analyzed chemically. The calcium concentration correlated well with the QCT density (r = 0.89, P less than 0.001). The highest correlation was recorded between the total calcium content in the scanned slices and the bone mass-related measures recorded by QCT (r = 0.96, P less than 0.001). Single-energy computed tomography thus provides an accurate measure of total bone mineral content.     

Treatment with raloxifene for 2 years increases vertebral bone mineral density as measured by volumetric quantitative computed tomography

Volumetric quantitative computed tomography (vQCT), using multiple thin-slice acquisition, measures three-dimensional volumetric bone mineral density (BMD, mg/cm3). vQCT is often used to measure BMD of lumbar vertebrae and may detect early changes in trabecular, cortical, or integral BMD that extend beyond the technical limits of areal dual X-ray absorptiometry (DXA) BMD measurements. The objective of this study was to determine the effect of 2 years of raloxifene (RLX) treatment on several volumetric BMD measures in a subset of postmenopausal women (n=58) enrolled in the Multiple Outcomes of Raloxifene Evaluation (MORE) trial. Patients in this study were randomized to one of three treatment groups: placebo (n=21), RLX 60 mg/day (n=17), or RLX 120 mg/day (n=20), and all patients received daily calcium (500 mg) and vitamin D (400-600 IU) supplementation. Data from the raloxifene treatment groups were pooled for each analysis. Following 2 years of raloxifene treatment, there was a significant percent change from baseline in the vQCT regions of interest (ROIs) of midintegral BMD, total trabecular BMD, and total integral BMD (P<0.05) compared to placebo, while there was no significant change in the spinal DXA BMD measurement. These data provide the first longitudinal assessment by vQCT of changes in vertebral bone density after 2 years of treatment with raloxifene. vQCT appears to be a valuable technique for measuring the effects of raloxifene treatment in this population of postmenopausal women with osteoporosis.     

定量CT椎体骨密度测定诊断骨质疏松症

[目的]探讨定量CT（QCT）椎体骨密度（BMD）测定在诊断骨质疏松症中的临床价值和诊断标准。[方法]对53例健康无症状中老年人和68例临床拟诊骨质疏松患者进行L1-4。椎体BMD测定。[结果]健康中老年人BMD随年龄增长而明显降低，有显著性差异。以BMD≤x-2．0 SD为诊断骨质量疏松症标准有68例，且各年龄段的BMD值均明显低于骨量截断值；如以BMD≤x-2．5 SD为诊断标准则有60例。[结论]QCT诊断骨质疏松症敏感、准确、重复性强，易于推广应用。以BMD≤x-2．0SD为诊断标准，更符合临床实际病例，并能减少漏诊。     

QCT椎体骨密度测定诊断骨质疏松症

目的 探讨定量CT(QCT)椎体骨密度(BMD)测定在诊断骨质疏松症中的临床价值和诊断标准.方法 对53例健康无症状中老年人和68例临床拟诊骨质疏松患者进行L1-L4椎体BMD测定.结果 健康中老年人BMD随年龄增长而明显降低,有显著性差异.以BMD≤x-2.0SD为诊断骨质疏松症标准有68例,且各年龄段的BMD值均明显低于骨量截断值;如以BMD≤x-2.5SD为诊断标准则有60例.结论 QCT诊断骨质疏松症敏感、准确、重复性强,易于推广应用.以BMD≤x-2.0SD为诊断标准,更符合临床实际病例,并能减少漏诊.     

Further improvements on the factors affecting bone mineral density measured by quantitative micro-computed tomography

The effects of imaging parameters and special configuration of objects within the reconstruction space on the micro computed tomography (μCT) based mineral density have been explored, and a series of density correction curves have been presented. A manufacturer-provided calibration phantom (0, 100, 200, 400, 800 mg HA/cm(3)) was imaged at all possible imaging conditions (n=216) based on energy, resolution, vial diameter, beam hardening correction factor and averaging. For each imaging condition, a linear regression model was fitted to the observed versus expected densities, and the intercepts (β(0)) and slopes (β(1)) of the regression lines and each density level were modeled using multiple regression modeling. Additionally, a custom made phantom (0, 50, 150, 500, 800, 1000 and 1500 mg HA/cm(3)) was scanned in order to study the effects of location and orientation of an object within the reconstruction space and presence of surrounding objects on μCT based mineral density. The energy, vial diameter and beam hardening correction factor were significant predictors of cumineral density (P values<0.001), while averaging and resolution did not have a significant effect on the observed density values (P values>0.1) except for 0.0 density (P values<0.04). Varying the location of an object within the reconstruction space from the center to the periphery resulted in a drop in observed mineral density up to 10% (P values<0.005). The presence of surrounding densities resulted in decreased observed mineral density up to 17% at the center and up to 14% at the periphery of the reconstruction space (P values<0.001 for all densities). Changing the orientation of the sample also had a significant effect on the observed mineral density, resulting in up to 16% lower observed mineral density for vertical vs. horizontal orientation at the center of the reconstruction space (P value<0.001). We conclude that energy, resolution and post processing correction factor are significant predictors of the observed mineral density in μCT.     

Evaluation of bone mineral density after instrumented lumbar fusion with computed tomography

BACKGROUND CONTEXTComputed tomography (CT) measurement of Hounsfield Units (HU) has been described as a tool for assessing BMD. For surgeons considering a revision lumbar fusion, knowledge of the BMD of the UIV is of value for surgical planning. However, the presence of metal artifact from instrumentation presents a potential confounder, and prior studies have not validated measurements of HU in this setting.PURPOSETo determine if HU can be measured reliably at the supra-adjacent and upper instrumented levels of a lumbar fusion.STUDY DESIGNRetrospective observational cohortPATIENT SAMPLEConsecutive series of patients who had lumbar CT scans after an instrumented posterior lumbar fusion.OUTCOME MEASURESHounsfield Units at the upper instrumented vertebra and levels proximal.METHODSWe analysed pre- and postoperative CT scans of 50 patients who underwent L2 and distal instrumented lumbar fusion whose scans were no greater than 1 year apart, obtaining HU measurements of analogous axial cuts at the upper instrumented level (immediately caudal to the halo of the pedicle screw), as well as additional control levels above the construct.RESULTSThe HU at the pre-and postoperative UIV exhibited a strong correlation (r=0.917, p<.001), as did one (r=0.887, p<.001) and two (r=0.853, p<.001) levels above the UIV. There were significant but predictable reductions in the postoperative HU compared to preoperative at one (-9.0±26.2) and two (-12.2±30.2) levels above the UIV, as well as T12 (-13.9±42.2). There was no significant difference in HU at the UIV (4.6±34.1).CONCLUSIONSPostoperative HU at the UIV was strongly correlated with and not significantly different from the preoperative HU. Although the HU in the vertebrae proximal to the UIV were slightly lower postoperatively, this change was predictable using a correction factor.     

Comparison of trabecular bone density at vertebral and radial sites using quantitative computed tomography

Trabecular volumetric bone mineral density (VMD) was measured at the lumbar spine using quantitative computed tomography (QCT) and at the distal radius using peripheral QCT (pQCT) in 60 Japanese women aged 21–86 years. The age-dependent decrease between age 20 and 80 years was found to be almost identical between vertebral trabecular VMD and radial trabecular VMD, averaging 2.5±0.26 (SE) and 2.5±0.30 mg/cm³ per year, respectively. A highly significant correlation was found between vertebral and radial trabecular VMD (r=0.806,p<0.001) with a prediction error of ±9.6% (± SD/mean). In the present study, a relatively constant trabecular VMD ratio was found between the vertebral and distal radial sites, despite the relatively small study population. This may indicate a close parallelism between vertebral and radial trabecular bone.