基于黄斑距离优化的视网膜OCT图像层次分割方法

Optimum hierarchical segmentation of OCT images in retina based on macular distance

视网膜分层是视盘结构三维分析、青光眼三维特征提取的基础,为改善视网膜OCT图像的层次分割效果,提出了一个基于强度的二维视网膜黄斑OCT图像多层结构分割算法。分割方法通过预处理、滤波等操作,计算出视网膜OCT图像中每个A-scan的强度和强度梯度值,能很好地分割出视网膜OCT图像中的RNFL上界、IS和OS分界线、RPE层下界等,并用最短距离计算的黄斑距离策略对黄斑部位分层结果进行再优化,从而实现视网膜OCT图像的层次分割。实验结果表明,所提算法优化效果好,时间复杂度低,运行速度较快。

Retina layering was the basis of optic disc structure analysis and 3D feature extraction of glaucoma. In order to improve the layering effect of retinal OCT images, an intensity based multilayer segmentation algorithm for two-dimensional retinal OCT images was proposed. Through preprocessing and filtering operation, the segmentation algorithm calculated the intensity and intensity gradient of each A-scan in the retinal OCT image to obtain the upper bound RNFL, the dividing line IS and OS, and the lower bound RPE. Then macular distance strategy, calculated by the shortest distance, was used to further optimize the layering result of macular area, so as to achieve layering segmentation of the retinal OCT images. The experimental results show the algorithm has good optimization effect, low time complexity and fast running speed.