摘要
PROPELLER数据采集成像算法是磁共振成像中的一项新技术,由于其数据的网格化直接影响该成像算法的效果,因此提出一种基于Voronoi图的网格化算法.该算法对采样数据集进行网格分组查找,快速消除位置相同点;加入边缘闭包后进行Voronoi网格化,计算Voronoi网格面积并将其作为网格化的密度补偿权函数,提出基于网格分组的快速网格化算法并成像.实验表明,该算法运行速度快,成像清晰,图像对比度和细节较好,信噪比得到有效提高.
PROPELLER (periodically rotated overlapping parallel lines with enhanced reconstruction) method is a new technique of MRI imaging, and the quality of the MRI images reconstructed by PROPELLER is seriously affected by data gridding. A new gridding method based on Voronoi diagrams was proposed. Firstly, the sampling data was grouped based on the grid, and the points with the same position were eliminated. Then, a closure was established round the sampling data. Voronoi diagrams were generated and their areas were used as the sampling density compensation in the gridding reconstruction. Finally, a rapid gridding algorithm based on grid-grouping was proposed. Experimental results demonstrate that the method can be used in MR image reconstruction to obtain clear images with high contrast and good details. The signal to noise ratio of images can be improved as well.
基金
国家自然科学基金(60771007)资助