Mukherjee Souvick, De Silva Tharindu, Grisso Peyton, Wiley Henry, Tiarnan D L Keenan, Thavikulwat Alisa T, Chew Emily, Cukras Catherine
Unit on Clinical Investigation of Retinal Disease, 10 Center Drive, Building 10-CRC Room 3-2531, MD 20892-1204, USA.
Division of Epidemiology and Clinical Applications in National Eye Institute, National Institutes of Health, Bethesda, MD 20892-4874, USA.
Biomed Opt Express. 2022 May 5;13(6):3195-3210. doi: 10.1364/BOE.450193. eCollection 2022 Jun 1.
Retinal layer segmentation in optical coherence tomography (OCT) images is an important approach for detecting and prognosing disease. Automating segmentation using robust machine learning techniques lead to computationally efficient solutions and significantly reduces the cost of labor-intensive labeling, which is traditionally performed by trained graders at a reading center, sometimes aided by semi-automated algorithms. Although several algorithms have been proposed since the revival of deep learning, eyes with severe pathological conditions continue to challenge fully automated segmentation approaches. There remains an opportunity to leverage the underlying spatial correlations between the retinal surfaces in the segmentation approach. Some of these proposed traditional methods can be expanded to utilize the three-dimensional spatial context governing the retinal image volumes by replacing the use of 2D filters with 3D filters. Towards this purpose, we propose a spatial-context, continuity and anatomical relationship preserving semantic segmentation algorithm, which utilizes the 3D spatial context from the image volumes with the use of 3D filters. We propose a 3D deep neural network capable of learning the surface positions of the layers in the retinal volumes. We utilize a dataset of OCT images from patients with Age-related Macular Degeneration (AMD) to assess performance of our model and provide both qualitative (including segmentation maps and thickness maps) and quantitative (including error metric comparisons and volumetric comparisons) results, which demonstrate that our proposed method performs favorably even for eyes with pathological changes caused by severe retinal diseases. The Mean Absolute Error (MAE) and Root Mean Squared Error (RMSE) for patients with a wide range of AMD severity scores (0-11) were within 0.84±0.41 and 1.33±0.73 pixels, respectively, which are significantly better than some of the other state-of-the-art algorithms. The results demonstrate the utility of extracting features from the entire OCT volume by treating the volume as a correlated entity and show the benefit of utilizing 3D autoencoder based regression networks for smoothing the approximated retinal layers by inducing shape based regularization constraints.
光学相干断层扫描(OCT)图像中的视网膜层分割是检测和预测疾病的重要方法。使用强大的机器学习技术实现分割自动化可带来计算效率高的解决方案,并显著降低劳动密集型标注的成本,传统上这种标注由阅读中心的训练有素的分级人员进行,有时还借助半自动算法。尽管自深度学习复兴以来已提出了多种算法,但患有严重病理状况的眼睛仍对全自动分割方法构成挑战。在分割方法中利用视网膜表面之间潜在的空间相关性仍存在机会。其中一些已提出的传统方法可以通过用3D滤波器替代2D滤波器的使用来扩展,以利用控制视网膜图像体积的三维空间上下文。为此,我们提出一种保留空间上下文、连续性和解剖关系的语义分割算法,该算法利用3D滤波器从图像体积中获取3D空间上下文。我们提出一种能够学习视网膜体积中层的表面位置的3D深度神经网络。我们利用来自年龄相关性黄斑变性(AMD)患者的OCT图像数据集来评估我们模型的性能,并提供定性(包括分割图和厚度图)和定量(包括误差度量比较和体积比较)结果,这些结果表明我们提出的方法即使对于患有由严重视网膜疾病引起的病理变化的眼睛也表现良好。对于具有广泛AMD严重程度评分(0 - 11)的患者,平均绝对误差(MAE)和均方根误差(RMSE)分别在0.84±0.41和1.33±0.73像素以内,这明显优于其他一些最先进的算法。结果证明了将体积视为相关实体从整个OCT体积中提取特征的实用性,并展示了利用基于3D自动编码器的回归网络通过引入基于形状的正则化约束来平滑近似视网膜层的好处。