Vajda E G, Skedros J G, Bloebaum R D
Bone and Joint Research Laboratory, VA Medical Center, Salt Lake City, Utah 84148, USA.
Scanning. 1998 Oct;20(7):527-35. doi: 10.1002/sca.1998.4950200708.
Backscattered electron (BSE) imaging has proven to be a useful method for analyzing the mineral distribution in microscopic regions of bone. However, an accepted method of standardization has not been developed, limiting the utility of BSE imaging for truly quantitative analysis. Previous work has suggested that BSE images can be standardized by energy-dispersive x-ray spectrometry (EDX). Unfortunately, EDX-standardized BSE images tend to underestimate the mineral content of bone when compared with traditional ash measurements. The goal of this study is to investigate the nature of the deficit between EDX-standardized BSE images and ash measurements. A series of analytical standards, ashed bone specimens, and unembedded bone specimens were investigated to determine the source of the deficit previously reported. The primary source of error was found to be inaccurate ZAF corrections to account for the organic phase of the bone matrix. Conductive coatings, methylmethacrylate embedding media, and minor elemental constituents in bone mineral introduced negligible errors. It is suggested that the errors would remain constant and an empirical correction could be used to account for the deficit. However, extensive preliminary testing of the analysis equipment is essential.
背散射电子（BSE）成像已被证明是分析骨微观区域矿物质分布的一种有用方法。然而，尚未开发出一种公认的标准化方法，这限制了BSE成像在真正定量分析中的效用。先前的研究表明，BSE图像可以通过能量色散X射线光谱法（EDX）进行标准化。不幸的是，与传统的灰分测量相比，经EDX标准化的BSE图像往往会低估骨的矿物质含量。本研究的目的是调查经EDX标准化的BSE图像与灰分测量之间差异的本质。研究了一系列分析标准品、灰化骨标本和未包埋骨标本，以确定先前报道的差异来源。发现误差的主要来源是对骨基质有机相进行的ZAF校正不准确。导电涂层、甲基丙烯酸甲酯包埋介质和骨矿物质中的微量元素成分引入的误差可忽略不计。建议误差将保持恒定，可使用经验校正来弥补差异。然而，对分析设备进行广泛的初步测试至关重要。
