Lidayová Kristína, Frimmel Hans, Bengtsson Ewert, Smedby Örjan
Uppsala University, Centre for Image Analysis, Division of Visual Information and Interaction, Uppsala, Sweden.
Uppsala University, Division of Scientific Computing, Department of Information Technology, Sweden.
J Med Imaging (Bellingham). 2017 Apr;4(2):024004. doi: 10.1117/1.JMI.4.2.024004. Epub 2017 Apr 28.
Vascular segmentation plays an important role in the assessment of peripheral arterial disease. The segmentation is very challenging especially for arteries with severe stenosis or complete occlusion. We present a cascading algorithm for vascular centerline tree detection specializing in detecting centerlines in diseased peripheral arteries. It takes a three-dimensional computed tomography angiography (CTA) volume and returns a vascular centerline tree, which can be used for accelerating and facilitating the vascular segmentation. The algorithm consists of four levels, two of which detect healthy arteries of varying sizes and two that specialize in different types of vascular pathology: severe calcification and occlusion. We perform four main steps at each level: appropriate parameters for each level are selected automatically, a set of centrally located voxels is detected, these voxels are connected together based on the connection criteria, and the resulting centerline tree is corrected from spurious branches. The proposed method was tested on 25 CTA scans of the lower limbs, achieving an average overlap rate of 89% and an average detection rate of 82%. The average execution time using four CPU cores was 70 s, and the technique was successful also in detecting very distal artery branches, e.g., in the foot.
血管分割在周围动脉疾病的评估中起着重要作用。这种分割极具挑战性，尤其是对于存在严重狭窄或完全闭塞的动脉。我们提出了一种用于血管中心线树检测的级联算法，专门用于检测病变外周动脉的中心线。它以三维计算机断层血管造影（CTA）容积作为输入，并返回一棵血管中心线树，可用于加速和辅助血管分割。该算法由四个层级组成，其中两个层级检测不同大小的健康动脉，另外两个层级专门处理不同类型的血管病变：严重钙化和闭塞。我们在每个层级执行四个主要步骤：自动选择每个层级的合适参数，检测一组位于中心的体素，根据连接标准将这些体素连接在一起，以及从伪分支中校正生成的中心线树。所提出的方法在25例下肢CTA扫描上进行了测试，平均重叠率达到89%，平均检测率为82%。使用四个CPU核心时的平均执行时间为70秒，该技术在检测非常远端的动脉分支（如足部的分支）时也很成功。
