Calibration of dual‐energy X‐ray absorptiometry for bone density
Calibration of dual‐energy X‐ray absorptiometry for bone density
复制标题
双能X射线骨密度测定法的校准
DOI：
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发表时间：
1991
影响因子：
6.2
通讯作者：
D. Hans
中科院分区：
文献类型：
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作者：
R. Mazess;J. Trempe;J. Bisek;J. Hanson;D. Hans
使用 Dexa (Lunar Dpx) 在水浴中、在存在均匀和不均匀的脂肪等效材料覆盖物的情况下测量已知的羟基磷灰石样品的骨矿物质含量 (Bmc、G)。在骨上选择性放置石蜡在减少表观 BMC 方面比猪油具有更大的效果，而聚碳酸酯塑料的效果较小。当 (1) 骨骼上的脂肪约为羟基磷灰石质量的两倍，并且 (2) 周围的软组织为 15-30% 脂肪时，测得的 BMC 为实际羟基磷灰石重量的 100.1 ± 1.1%。使用 Lunar DPX 或 Hologic QDR-1000 在铝体模上测量的观察值和预期 Bmc、面积 (Cm2) 和骨矿物质密度 (BMD, g/cm2) 之间存在线性关系。两个密度计测量的面积相同，但 BMC 不同。对于拟人体模和人类受试者，与标准 DPX 边缘检测算法相比，使用恒定阈值 (0.2 g/cm2) 边缘检测算法从横突中排除的低密度骨较少。边缘检测的差异可能会影响体模和体内获得的结果，并使系统相互比较变得困难。
Bone Mineral Content (Bmc, G) Using Dexa (Lunar Dpx) Was Measured On Known Hydroxyapatite Samples In A Water Bath In The Presence Of Uniform And Nonuniform Coverings Of Fat‐Equivalent Materials. Selective Placement Of Paraffin Over Bone Had A Greater Effect Than Lard In Reducing Apparent Bmc, And Polycarbonate Plastic Had A Lesser Effect. Measured Bmc Was 100.1 ± 1.1% Of Actual Hydroxyapatite Weight When (1) Fat Over Bone Was About Twice The Mass Of Hydroxyapatite, And (2) The Surrounding Soft Tissue Was 15–30% Fat. There Was A Linear Relationship Between Observed And Expected Bmc, Area (Cm2), and bone mineral density (BMD, g/cm2) measured on an aluminum phantom using either the Lunar DPX or the Hologic QDR‐1000. The measured area with the two densitometers was identical, but BMC differed. For both an anthropomorphic phantom and human subjects, use of a constant‐threshold (0.2 g/cm2) edge‐detection algorithm excluded less low‐density bone from the transverse processes than the standard DPX edge‐detection algorithm. Differences in edge detection could influence the results obtained with phantoms and in vivo and make system intercomparison difficult.