Pereira Renata C, Bischoff David S, Yamaguchi Dean, Salusky Isidro B, Wesseling-Perry Katherine
Department of Pediatrics, David Geffen School of Medicine at the University of California, Los Angeles, Los Angeles, California; and.
Department of Medicine, Veterans Affairs Sepulveda and David Geffen School of Medicine at the University of California, Los Angeles, Los Angeles, California.
Clin J Am Soc Nephrol. 2016 Mar 7;11(3):481-7. doi: 10.2215/CJN.04810515. Epub 2015 Dec 28.
Computed tomography (CT) measurements can distinguish between cortical and trabecular bone density in vivo. High-resolution CTs assess both bone volume and density in the same compartment, thus potentially yielding information regarding bone mineralization as well. The relationship between bone histomorphometric parameters of skeletal mineralization and bone density from microcomputed tomography (μCT) measurements of bone cores from patients on dialysis has not been assessed.
DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Bone cores from 68 patients with ESRD (age =13.9±0.5 years old; 50% men) and 14 controls (age =15.3±3.8 years old; 50% men) obtained as part of research protocols between 1983 and 2006 were analyzed by bone histomorphometry and μCT.
Bone histomorphometric diagnoses in the patients were normal to high bone turnover in 76%, adynamic bone in 13%, and osteomalacia in 11%. Bone formation rate did not correlate with any μCT determinations. Bone volume measurements were highly correlated between bone histomorphometry and μCT (bone volume/tissue volume between the two techniques: r=0.70; P<0.001, trabecular thickness and trabecular separation: r=0.71; P<0.001, and r=0.56; P<0.001, respectively). Osteoid accumulation as determined by bone histomorphometry correlated inversely with bone mineral density as assessed by μCT (osteoid thickness: r=-0.32; P=0.01 and osteoid volume: r=-0.28; P=0.05). By multivariable analysis, the combination of bone mineral density and bone volume (as assessed by μCT) along with parathyroid hormone and calcium levels accounted for 38% of the variability in osteoid volume (by histomorphometry).
Measures of bone volume can be accurately assessed with μCT. Bone mineral density is lower in patients with excessive osteoid accumulation and higher in patients with adynamic, well mineralized bone. Thus, bone mineralization may be accurately assessed by μCT of bone biopsy cores. Additional studies are warranted to define the value of high-resolution CT in the prediction of bone mineralization in vivo.
计算机断层扫描（CT）测量可在体内区分皮质骨和小梁骨密度。高分辨率CT可评估同一骨腔室的骨体积和密度，因此也可能提供有关骨矿化的信息。尚未评估透析患者骨芯的微计算机断层扫描（μCT）测量所得的骨骼矿化骨组织形态计量学参数与骨密度之间的关系。
设计、场所、参与者及测量方法：对1983年至2006年间作为研究方案一部分获取的68例终末期肾病患者（年龄=13.9±0.5岁；50%为男性）和14例对照者（年龄=15.3±3.8岁；50%为男性）的骨芯进行骨组织形态计量学和μCT分析。
患者的骨组织形态计量学诊断结果为：76%为正常至高骨转换，13%为骨动力不足，11%为骨软化。骨形成率与任何μCT测定结果均无相关性。骨组织形态计量学与μCT之间的骨体积测量结果高度相关（两种技术之间的骨体积/组织体积：r=0.70；P<0.001，小梁厚度和小梁间距：r分别为0.71；P<0.001和0.56；P<0.001）。骨组织形态计量学测定的类骨质积聚与μCT评估的骨矿物质密度呈负相关（类骨质厚度：r=-0.32；P=0.01，类骨质体积：r=-0.28；P=0.05）。通过多变量分析，骨矿物质密度和骨体积（通过μCT评估）与甲状旁腺激素和钙水平的组合占类骨质体积（通过组织形态计量学）变异性的38%。
μCT可准确评估骨体积测量值。类骨质积聚过多的患者骨矿物质密度较低，骨动力不足、矿化良好的患者骨矿物质密度较高。因此，通过骨活检芯的μCT可准确评估骨矿化情况。有必要进行更多研究以确定高分辨率CT在体内预测骨矿化中的价值。
