Wu C Y, Glüer C C, Jergas M, Bendavid E, Genant H K
Department of Radiology, University of California, San Francisco 94143-0628, USA.
Bone. 1995 Jan;16(1):137-41.
Quantitative ultrasound (QUS) is a simple, inexpensive and radiation-free technique to study skeletal status in osteoporosis. Broadband ultrasound attenuation (BUA) is typically used without normalizing for bone thickness. We investigated the impact of bone thickness on BUA, both in in vitro and in vivo, using commercially available ultrasound scanners (Walker Sonix UBA 575 and 575+). For the study in vitro, we analyzed 12 paired cubes (12 x 12 x 12 mm3) of bovine trabecular bone cut from six "parent" blocks (24 x 12 x 12 mm3). These "parent" blocks showed a fairly homogeneous structure as assessed by conventional radiography. BUA and dual x-ray absorptiometry (DXA) measurements of bone mineral density (BMD) were obtained. The difference between the paired cubes was significant for BUA (p < 0.001), but not for BMD (p > 0.05). The BUA of the "parent" blocks was larger by 32-92% than the average BUA of the corresponding paired cubes, and always less than the sum of the paired cubes (5-34%). BUA thus added up in a complex and nonlinear fashion. Measurements in vivo of the calcaneal bone width demonstrated on radiographs (study in vivo I, 28 postmenopausal women) and CT images (study in vivo II, 17 women) showed a small, positive but not significant correlation with BUA (r2 = 0.13 and r2 = 0.007, p > 0.05). The magnitude of this effect provides further evidence that BUA does not scale linearly with bone size. Our results indicate that simple normalization of BUA data by specifying the results in decibels per megahertz per millimeter units may not be appropriate.(ABSTRACT TRUNCATED AT 250 WORDS)
定量超声（QUS）是一种用于研究骨质疏松症骨骼状况的简单、廉价且无辐射的技术。宽带超声衰减（BUA）通常在未对骨厚度进行标准化的情况下使用。我们使用市售超声扫描仪（沃克Sonix UBA 575和575+），在体外和体内研究了骨厚度对BUA的影响。对于体外研究，我们分析了从六个“母体”块（24×12×12 mm³）切下的12对牛松质骨立方体（12×12×12 mm³）。通过传统X线摄影评估，这些“母体”块显示出相当均匀的结构。获得了骨密度（BMD）的BUA和双能X线吸收法（DXA）测量值。配对立方体之间的差异在BUA方面具有显著性（p < 0.001），但在BMD方面不具有显著性（p > 0.05）。“母体”块的BUA比相应配对立方体的平均BUA大32% - 92%，且始终小于配对立方体之和（5% - 34%）。因此，BUA以复杂的非线性方式累加。在X线片上显示的跟骨宽度的体内测量（体内研究I，28名绝经后女性）以及CT图像（体内研究II，17名女性）显示，与BUA存在小的正相关但不显著（r² = 0.13和r² = 0.007，p > 0.05）。这种效应的大小提供了进一步的证据，表明BUA与骨大小并非线性相关。我们的结果表明，通过指定以每兆赫兹每毫米分贝为单位的结果对BUA数据进行简单标准化可能不合适。（摘要截取自250字）
