Boundary segmentation based on modified random walks for vascular Doppler optical coherence tomography images

Vascular Doppler optical coherence tomography(DOCT) images with weak boundaries are usually difficult for most algorithms to segment. We propose a modified random walk(MRW) algorithm with a novel regularization for the segmentation of DOCT vessel images. Based on MRW, we perform automatic boundary detection of the vascular wall from intensity images and boundary extraction of the blood flowing region from Doppler phase images. Dice, sensitivity, and specificity coefficients were adopted to verify the segmentation performance. The experimental study on DOCT images of the mouse femoral artery showed the effectiveness of our proposed method, yielding three-dimensional visualization and quantitative evaluation of the vessel.     

多模态图像引导手术导航进展

手术导航综合运用器官分割建模与手术规划、位姿标定与跟踪定位、多模态图像配准与融合显示等技术，使医生精确定位病灶与手术工具的位置，透过组织表面对内部组织进行观测，可大幅提升手术的安全性，缩短手术时间并提高手术效率。常规手术通常使用超声、内窥镜或X光等单模态影像进行手术过程引导，信息单一且均为二维影像，空间立体信息缺失，手术过程严重依赖医生经验；而多模态图像引导的手术导航技术通过融合多模态图像的优势，在三维空间提供病灶的结构或功能信息，大幅提升医生对血管、神经以及重要组织结构的空间辨识力。由此，本文针对多模态图像分割建模、手术方案决策、手术空间位姿标定与跟踪、多模态图像配准、图像融合与显示等多模态图像引导手术导航的关键技术进行总结和分析，提出其进一步发展面临的挑战并展望其未来发展趋势。多模态图像引导手术导航技术已成为神经外科、颅颌面、骨科、经皮穿刺、血管介入等临床科室精准治疗的新兴手段，具有重要的应用前景。