Chang Herng-Hua, Valentino Daniel J, Duckwiler Gary R, Toga Arthur W
Biomedical Engineering IDP and Laboratory of Neuro Imaging, University of California at Los Angeles, UCLA Radiology Mail Stop 172115, Los Angeles, CA 90095-1721, USA.
IEEE Trans Biomed Eng. 2007 Oct;54(10):1798-813. doi: 10.1109/TBME.2007.895104.
In this paper, we developed a new deformable model, the charged fluid model (CFM), that uses the simulation of a charged fluid to segment anatomic structures in magnetic resonance (MR) images of the brain. Conceptually, the charged fluid behaves like a liquid such that it flows through and around different obstacles. The simulation evolves in two steps governed by Poisson's equation. The first step distributes the elements of the charged fluid within the propagating interface until an electrostatic equilibrium is achieved. The second step advances the propagating front of the charged fluid such that it deforms into a new shape in response to the image gradient. This approach required no prior knowledge of anatomic structures, required the use of only one parameter, and provided subpixel precision in the region of interest. We demonstrated the performance of this new algorithm in the segmentation of anatomic structures on simulated and real brain MR images of different subjects. The CFM was compared to the level-set-based methods [Caselles et al. (1993) and Malladi et al (1995)] in segmenting difficult objects in a variety of brain MR images. The experimental results in different types of MR images indicate that the CFM algorithm achieves good segmentation results and is of potential value in brain image processing applications.
在本文中,我们开发了一种新的可变形模型——带电流体模型(CFM),该模型利用带电流体模拟对脑部磁共振(MR)图像中的解剖结构进行分割。从概念上讲,带电流体的行为类似于液体,能够在不同障碍物之间流动并绕过它们。模拟过程分两步进行,由泊松方程控制。第一步是在传播界面内分布带电流体的元素,直至达到静电平衡。第二步推进带电流体的传播前沿,使其根据图像梯度变形为新的形状。这种方法无需解剖结构的先验知识,仅需使用一个参数,并在感兴趣区域提供亚像素精度。我们在不同受试者的模拟和真实脑部MR图像上展示了这种新算法在解剖结构分割方面的性能。在对各种脑部MR图像中的困难物体进行分割时,将CFM与基于水平集的方法[卡塞莱斯等人(1993年)和马拉迪等人(1995年)]进行了比较。不同类型MR图像的实验结果表明,CFM算法取得了良好的分割效果,在脑图像处理应用中具有潜在价值。