Lee Taekhee, Barone Teresa, Rubinstein Elaine, Mischler Steven
Health Hazards Prevention Branch, Pittsburgh Mining Research Division, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Pittsburgh, Pennsylvania, USA.
Human Systems Integration Branch, Pittsburgh Mining Research Division, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Pittsburgh, Pennsylvania, USA.
J Occup Environ Hyg. 2022 Jun;19(6):370-380. doi: 10.1080/15459624.2022.2063878. Epub 2022 May 5.
The objective of the present study is to find a fast and accurate procedure to measure the length and width of asbestos fibers using images acquired by a scanning electron microscope (SEM), a phase-contrast microscope (PCM), and a polarized light microscope (PLM). The accuracy of the procedure was evaluated by comparing fiber length and width measurements to manual measurements. Four different types of images were used in the evaluation: (1) backscattered electron SEM images of fibrous tremolite, (2) secondary electron SEM images of fibrous grunerite, (3) PCM images of fibrous grunerite, and (4) PLM images of fibrous grunerite. Fiber length and width were measured with ImageJ (manual measurement) and Image-Pro software and were compared on an individual fiber basis and over the number-length and number-width distribution of each sample. The results of the comparison showed that the individual length and width measurements with ImageJ and Image-Pro software had a nearly 1:1 relationship except for the width measurement in PLM images (8% of the variance in ImageJ width measurements was not explained by Image-Pro width measurements). Similarly, the number-length distributions were not significantly different ( > 0.05) between ImageJ and Image-Pro, but the number-width distributions were significantly different ( < 0.05) for PLM and secondary electron SEM images. Although the image analysis procedure for measuring fiber length and width with Image-Pro is not a fully automated procedure and still requires some manual intervention, it can be a more efficient and equally accurate alternative to time-consuming manual fiber length and width measurements for well dispersed fibers with high aspect ratios.
本研究的目的是找到一种快速准确的程序，利用扫描电子显微镜（SEM）、相差显微镜（PCM）和偏振光显微镜（PLM）获取的图像来测量石棉纤维的长度和宽度。通过将纤维长度和宽度测量值与手动测量值进行比较，评估该程序的准确性。评估中使用了四种不同类型的图像：（1）纤维透闪石的背散射电子SEM图像，（2）纤维铁闪石的二次电子SEM图像，（3）纤维铁闪石的PCM图像，以及（4）纤维铁闪石的PLM图像。使用ImageJ（手动测量）和Image-Pro软件测量纤维长度和宽度，并在单根纤维基础上以及每个样品的数量-长度和数量-宽度分布上进行比较。比较结果表明，除了PLM图像中的宽度测量外，使用ImageJ和Image-Pro软件进行的单根长度和宽度测量具有近乎1:1的关系（ImageJ宽度测量中8%的方差无法由Image-Pro宽度测量解释）。同样，ImageJ和Image-Pro之间的数量-长度分布没有显著差异（>0.05），但PLM和二次电子SEM图像的数量-宽度分布存在显著差异（<0.05）。尽管使用Image-Pro测量纤维长度和宽度的图像分析程序不是一个完全自动化的程序，仍然需要一些人工干预，但对于高纵横比且分散良好的纤维，它可以是一种比耗时的手动纤维长度和宽度测量更高效且同样准确的替代方法。
