Zamburlini M, Pejović-Milić A, Chettle D R, Webber C E, Gyorffy J
Medical Physics and Applied Radiation Science, McMaster University, Hamilton, L8S 4K1, Canada.
Phys Med Biol. 2007 Apr 21;52(8):2107-22. doi: 10.1088/0031-9155/52/8/005. Epub 2007 Mar 26.
An x-ray fluorescence (XRF) system using 125I as the source was developed to measure strontium in bone in vivo. As part of an in vivo pilot study, 22 people were measured at two bone sites, namely the index finger and the tibial ankle joint. Ultrasound measurements were used to obtain the soft tissue thickness at each site, which was necessary to correct the signal for tissue attenuation. For all 22 people, the strontium peak was clearly distinguishable from the background, proving that the system is able to measure Sr in vivo in people having normal bone Sr levels. Monte Carlo simulations were carried out to test the feasibility and the limitations of using the coherently scattered peak at 35.5 keV as a means to normalize the signal to correct for the bone size and shape. These showed that the accuracy of the normalized Sr signal when comparing different people is about 12%. An interesting result arising from the study is that, in the measured population, significantly higher measurements of bone Sr concentration were observed in continental Asian people, suggesting the possibility of a dietary or race dependence of the bone Sr concentration or a different bone biology between races.
开发了一种使用¹²⁵I作为源的X射线荧光（XRF）系统，用于在体内测量骨骼中的锶。作为体内初步研究的一部分，对22人在两个骨骼部位进行了测量，即食指和胫踝关节。使用超声测量来获取每个部位的软组织厚度，这对于校正组织衰减信号是必要的。对于所有22人，锶峰与背景明显可区分，证明该系统能够在骨骼锶水平正常的人体内测量锶。进行了蒙特卡罗模拟，以测试使用35.5 keV处的相干散射峰作为归一化信号以校正骨骼大小和形状的可行性和局限性。结果表明，在比较不同人时，归一化锶信号的准确度约为12%。该研究产生的一个有趣结果是，在被测人群中，观察到亚洲大陆人群的骨骼锶浓度测量值明显更高，这表明骨骼锶浓度可能存在饮食或种族依赖性，或者不同种族之间存在不同的骨骼生物学特性。
