Malek A M, Izumo S, Alper S L
Brigham & Women's Hospital/Children's Hospital, Department of Neurosurgery, Boston, MA 02115, USA.
Biotechniques. 1997 Jun;22(6):1150-3.
We describe here a novel method that relies on a digital imaging device to perform densitometric quantitation of radiographs in the laboratory setting. Using fluorescent back-illumination and appropriate exposure settings, a commercially available handheld charge-coupled device (CCD) digital camera is used to acquire the image of the radiograph. Following acquisition, the image is downloaded by means of a serial interface to a personal computer. There, it is analyzed to ensure that the series of pixel intensities lie within the linear range and then quantitated using two-dimensional integration with local background substraction. Using a linear dot blot established with serial dilution of 32P and imaging with standard radiographic film, we found that images acquired using the handheld digital camera were comparable to those input with a desktop scanner in transmittance mode. Quantitative densitometric analysis showed similar linear results between the digital camera and the desktop scanner over the 16-fold linear response of the radiographic film, both of which were comparable to phosphor imaging over that limited range. These findings demonstrate that the ever-improving technology of handheld digital imaging should be added to the repertoire of techniques for quantitative densitometry.
我们在此描述一种新方法，该方法依靠数字成像设备在实验室环境中对X光片进行密度定量分析。利用荧光背照光和适当的曝光设置，使用市售的手持式电荷耦合器件（CCD）数码相机获取X光片的图像。采集后，通过串行接口将图像下载到个人计算机。在计算机上，对图像进行分析以确保一系列像素强度处于线性范围内，然后使用二维积分和局部背景扣除进行定量分析。使用通过对32P进行系列稀释建立的线性点杂交，并使用标准X光胶片成像，我们发现使用手持式数码相机获取的图像在透射模式下与使用台式扫描仪输入的图像相当。定量密度分析表明，在X光胶片的16倍线性响应范围内，数码相机和台式扫描仪之间的线性结果相似，在该有限范围内两者均与磷光成像相当。这些发现表明，不断改进的手持式数字成像技术应添加到定量密度测定技术的方法库中。
