Ge Y, Udupa J K, Nyúl L G, Wei L, Grossman R I
Department of Radiology, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania 19104-6021, USA.
J Magn Reson Imaging. 2000 Nov;12(5):715-21. doi: 10.1002/1522-2586(200011)12:5<715::aid-jmri8>3.0.co;2-d.
Image intensity standardization is a recently developed postprocessing method that is capable of correcting the signal intensity variations in MR images. We evaluated signal intensity of healthy and diseased tissues in 10 multiple sclerosis (MS) patients based on standardized dual fast spin-echo MR images using a numerical postprocessing technique. The main idea of this technique is to deform the volume image histogram of each study to match a standard histogram and to utilize the resulting transformation to map the image intensities into standard scale. Upon standardization, the coefficients of variation of signal intensities for each segmented tissue (gray matter, white matter, lesion plaques, and diffuse abnormal white matter) in all patients were significantly smaller (2.3-9.2 times) than in the original images, and the same tissues from different patients looked alike, with similar intensity characteristics. Numerical tissue characterizability of different tissues in MS achieved by standardization offers a fixed tissue-specific meaning for the numerical values and can significantly facilitate image segmentation and analysis.
图像强度标准化是一种最近开发的后处理方法，能够校正磁共振图像中的信号强度变化。我们使用一种数值后处理技术，基于标准化的双快速自旋回波磁共振图像，评估了10例多发性硬化症（MS）患者健康组织和病变组织的信号强度。该技术的主要思想是使每个研究的体图像直方图变形，以匹配标准直方图，并利用所得变换将图像强度映射到标准尺度。标准化后，所有患者中每个分割组织（灰质、白质、病变斑块和弥漫性异常白质）的信号强度变异系数明显小于原始图像（2.3至9.2倍），并且来自不同患者的相同组织看起来相似，具有相似的强度特征。通过标准化实现的MS中不同组织的数值组织可表征性为数值提供了固定的组织特异性含义，并可显著促进图像分割和分析。
