Duerinckx A J, Macovski A
Med Phys. 1980 Mar-Apr;7(2):127-34. doi: 10.1118/1.594771.
In conventional computed tomography images only the average CT number, which is a first-order statistical parameter, is used to characterize the tissues by giving an estimate of tissue density. Second order statistical parameters such as the signal variance and cross-correlation function have also been used to obtain additional information to discriminate between certain tissues and lesions. However, the contribution of quantum noise to the signal variance and cross-correlation function creates, for the conventional CT patient dose, a background signal often larger than the signal containing the information about tissue structure. The misleading information, called "artifacts", in second-order image statistics caused by quantum noise, is studied.
在传统的计算机断层扫描图像中，仅使用平均CT值（它是一阶统计参数）通过估计组织密度来表征组织。二阶统计参数，如信号方差和互相关函数，也已被用于获取额外信息，以区分某些组织和病变。然而，对于传统CT的患者剂量，量子噪声对信号方差和互相关函数的贡献会产生一个背景信号，该背景信号通常大于包含组织结构信息的信号。本文研究了由量子噪声引起的二阶图像统计中的误导性信息，即“伪影”。
