基于灰度和空间联合信息最小化的磁共振图像偏差场纠正(英文)  

MRI Intensity Inhomogeneity Correction by Minimizing Joint Information of Intensity and Space

作　　者：刘常春[1] 胡顺波[1] 顾建军[1] 杨金宝[1] 

机构地区：[1]山东大学控制科学与工程学院,山东济南250061

出　　处：《光子学报》2007年第9期1747-1753,共7页Acta Photonica Sinica

基　　金：Supported by The Hi-Tech Research and Development Program(863) of China (2006AA02Z4D9);Shandong Province Nature Science Fundation (Z2006C05)

摘　　要：在磁共振图像( MR)的偏差场纠正中,针对灰度信息最小化方法没有考虑空间信息问题,提出联合信息最小化方法,该方法把图像的灰度信息和空间信息结合起来.空间信息采用灰度导数信息.被偏差场破坏的图像灰度及其导数值的联合信息(联合熵)大于对应的没被偏差场破坏的图像联合熵.联合熵是通过计算灰度及其导数值的联合概率分布得到.仿真脑部MR数据和临床脑部MR数据的试验结果都表明,灰度及其二阶导数联合信息最小化方法纠正效果良好,大大减少了脑白质和脑灰质的灰度交叠.In the intensity inhomogeneity correction of magnetic resonance imaging, since entropy minimization method did not consider space information, a better correction method based on joint information minimization was proposed, which integrated image intensity features with additional spatial image features. The space features referred to intensity derivatives. The joint entropy between image intensities and corresponding derivatives in a corrupted image is greater than that in an uncorrupted one, and it is calculated by using the joint probability distribution of image intensities and corresponding derivatives. The results on simulated brain images and clinical brain MR images show that joint information minimization method between intensities and their second derivatives is good. It can largely decrease the overlap between white matter and gray matter.

关 键 词：图像处理 偏差场纠正 磁共振成像 联合熵最小化 

分 类 号：R318[医药卫生—生物医学工程]