摘要
共聚焦激光显微内镜技术可以实时、原位获取细胞级图像,能够辅助医生术中实时诊断,但是其无创性给重新定位光学活检部位带来了困难。共聚焦探针定位算法可以自动计算探针尖端坐标,即光学活检部位坐标。本文提出了一种基于区域生长和内窥镜尺寸先验的共聚焦探针定位算法,该算法在探针边缘图像上通过区域生长检测探针区域,随后基于给定的探针轴线搜索尖端点,并迭代优化。最后基于探针单自由度运动特点,利用内窥镜的尺寸先验信息计算出探针尖端点的三维坐标,解决了单目相机的尺度不确定问题。在本文采集到的数据集上对共聚焦探针定位算法进行测试,结果表明,该算法不再依赖于探针的颜色信息,避免了光照不均匀对探针像素灰度值的影响,具有较鲁棒的定位精度和运行速度。在探针伸出内窥镜0~5 cm的长度范围内,像素误差最低可达11.76像素,平均相对位置误差最低可达1.66 mm,能够实时、准确地实现共聚焦探针的定位。
Confocal laser endomicroscopy technology can obtain cell-level images in real time and in situ, which can assist doctors in real-time intraoperative diagnosis, but its non-invasiveness makes it difficult to relocate the optical biopsy site. The confocal probe localization algorithm can automatically calculate the coordinates of the probe tip, that is,the coordinates of the optical biopsy site. In this paper, a confocal probe localization algorithm based on region growing and endoscope size prior was proposed. The algorithm detected the probe region by region growing on the probe edge image, then searched for tip points based on a given probe axis, and iteratively optimized it. Finally, based on the singledegree-of-freedom motion characteristics of the probe, the three-dimensional coordinates of the tip of the probe were calculated by using the prior information of the size of the endoscope, which solved the scale uncertainty problem of the monocular camera. The confocal probe localization algorithm was tested on the dataset collected in this paper. The results showed that our algorithm no longer relied on the color information of the probe, avoided the influence of uneven illumination on the gray value of the probe pixels, and had a more robust location accuracy and running speed. Within the length of the probe extending out of the endoscope from 0 to 5 cm, the pixel error could be as low as 11.76 pixels, and the average relative position error could be as low as 1.66 mm, which can achieve the real-time and accurate localization of the confocal probe.
作者
刘玉莹
王一帆
左思洋
LIU Yuying;WANG Yifan;ZUO Siyang(School of Mechanical Engineering,Tianjin University,Tianjin 300350,P.R.China)
出处
《生物医学工程学杂志》
EI
CAS
CSCD
北大核心
2022年第5期945-957,共13页
Journal of Biomedical Engineering
基金
国家重点研发计划(2019YFB1311501)
国家自然科学基金(62133010)。
