基于改进分水岭的CTA去骨技术①

为避免快速分水岭在CTA图像去骨中存在的过分割现象,采用一种改进的可交互分水岭算法对CTA图像进行去骨研究。改进算法建立在快速分水岭的排序操作基础上,排序完成后,采用侧重于像素空间关系的方法对像素进行溢流标记,同时采用树结构组织水盆及其合并关系,最后通过用户给定标记和合并阈值对集水盆合并过程进行干预,从而影响分割结果以抑制过分割。实验结果表明,改进算法有效地解决了分水岭变换中的过分割问题,并较好地去除骨骼结构。

Improved Watershed Algorithm for Bone Removal from CTA

In this paper, we present an improved interactive watershed algorithm for bone removal from CTA (Computed Tomography Angiography). The improved watershed algorithm builds upon the sorting step of the fast immersion-based watershed transform. After the sorting step, each element is processed with the respect to its neighborhood in the specified order, and the resulting basins are organized in a tree structure. After that, the tree partitioning and basin merging are controlled by one global parameter called merging value and some markers are given by users to suppresses the over segmentation. The experiment indicates that the algorithm prevents the over segmentation effectively, and removes the bone structure excellently.