There remain many unanswered questions on how to assess and treat the pathology and complications that arise from diabetic retinopathy (DR). Optical coherence tomography angiography (OCTA) is a novel and non-invasive three-dimensional imaging method that can visualize capillaries in all retinal layers. Numerous studies have confirmed that OCTA can identify early evidence of microvascular changes and provide quantitative assessment of the extent of diseases such as DR and its complications.

A number of informative OCTA metrics could be used to assess DR in clinical trials, including measurements of the foveal avascular zone (FAZ; area, acircularity, 3D para-FAZ vessel density), vessel density, extrafoveal avascular zones, and neovascularization. Assessing patients with DR using a full-retinal slab OCTA image can limit segmentation errors and confounding factors such as those related to center-involved diabetic macular edema. Given emerging data suggesting the importance of the peripheral retinal vasculature in assessing and predicting DR progression, wide-field OCTA imaging should also be used. Finally, the use of automated methods and algorithms for OCTA image analysis, such as those that can distinguish between areas of true and false signals, reconstruct images, and produce quantitative metrics, such as FAZ area, will greatly improve the efficiency and standardization of results between studies.

Most importantly, clinical trial protocols should account for the relatively high frequency of poor-quality data related to sub-optimal imaging conditions in DR and should incorporate time for assessing OCTA image quality and re-imaging patients where necessary.

关于如何评估和治疗糖尿病视网膜病变 (DR) 引起的病理和并发症，仍有许多未解答的问题。光学相干断层扫描血管造影（OCTA）是一种新颖的非侵入性三维成像方法，可以可视化所有视网膜层的毛细血管。大量研究证实，OCTA可以识别微血管变化的早期证据，并对DR及其并发症等疾病的程度提供定量评估。

许多信息丰富的 OCTA 指标可用于评估临床试验中的 DR，包括中心凹无血管区（FAZ；面积、非循环性、3D para-FAZ 血管密度）、血管密度、中心凹外无血管区和新血管形成的测量。使用全视网膜平板 OCTA 图像评估 DR 患者可以限制分割错误和混杂因素，例如与中心参与的糖尿病黄斑水肿相关的因素。鉴于新出现的数据表明周边视网膜血管系统在评估和预测 DR 进展方面的重要性，还应使用宽视野 OCTA 成像。最后，使用自动化方法和算法进行 OCTA 图像分析，例如能够区分真假信号区域、重建图像以及产生定量指标（例如 FAZ 面积）的方法和算法，将大大提高结果的效率和标准化学习之间。

最重要的是，临床试验方案应考虑到 DR 中与次优成像条件相关的相对较高频率的低质量数据，并应纳入评估 OCTA 图像质量和必要时对患者重新成像的时间。