Applicability of portable retinal cameras and telemedicine as facilitating tools in screening diabetic retinopathy in the COVID-19 pandemic scenario

ABSTRACT Purpose: Diabetes mellitus is a leading cause of impaired vision. The objective of this study was to evaluate the feasibility of use of portable retinograph and remote analysis of images along with a virtual questionnaire for screening for diabetic retinopathy in basic health units in the city of Ribeirão Preto/SP during the Covid-19 pandemic. Methods: Standard Covid-19 protocol was followed during the screening. Blood pressure and capillary blood glucose were measured. Demographic and social data were collected through a standardized online questionnaire via smartphone. After pupillary dilation, fundal images were obtained with portable retinographs by trained ophthalmology residents. Two standardized 45° images were acquired: one posterior segment and another nasal to the optic nerve. Diabetic retinopathy was classified according to the Early Treatment Diabetic Retinopathy Study. Results: A total of 350 patients (64% female; 45% aged 55-70 years; 55% Caucasian) were evaluated. For 40.5% of patients, the campaign was the first opportunity for retinal evaluation; 47.56% had diabetes mellitus for >10 years. On repeat analysis of images stored in a cloud-based repository by retinal specialist, a 7.8% difference was observed in the Early Treatment Diabetic Retinopathy Study diabetic retinopathy classification, compared to the screening findings. Mild diabetic retinopathy was observed in 12.23%, moderate diabetic retinopathy in 6.31%, and proliferative diabetic retinopathy in 2.58% patients. Macular edema was present in 4.58% patients. Diabetic retinopathy was not detected in 72.78% patients. Conclusion: Use of portable retinographs together with telemedicine can provide efficient alternative to traditional methods for screening and diagnosis of diabetic retinopathy.

摘要
目的：糖尿病是引发视力损害的主要病因。本研究旨在评估新冠疫情期间，于巴西圣保罗州里贝朗普雷图市基层卫生机构中，使用便携式视网膜照相机（portable retinograph）、图像远程分析结合虚拟问卷开展糖尿病视网膜病变（diabetic retinopathy）筛查的可行性。
方法：筛查过程严格遵循新冠防控标准流程。测量受试者血压与毛细血管血糖值，通过智能手机端的标准化线上问卷收集人口统计学与社会经济学数据。散瞳后，由经过培训的眼科住院医师使用便携式视网膜照相机拍摄眼底图像，采集两张标准化45°眼底图像：一张为后极部图像，另一张为视神经鼻侧图像。糖尿病视网膜病变的分级参照《早期糖尿病视网膜病变治疗研究》（Early Treatment Diabetic Retinopathy Study）标准进行。
结果：本研究共纳入350例受试者（女性占64%；45%的受试者年龄为55~70岁；55%为白人）。其中40.5%的受试者此次筛查为其首次接受眼底检查；47.56%的受试者糖尿病病程超过10年。由视网膜专科医师对存储于云存储库中的图像进行复阅分析后发现，与初筛结果相比，糖尿病视网膜病变的早期糖尿病视网膜病变治疗研究分级结果存在7.8%的差异。12.23%的受试者被检出轻度糖尿病视网膜病变，6.31%为中度糖尿病视网膜病变，2.58%为增殖性糖尿病视网膜病变；4.58%的受试者合并黄斑水肿；72.78%的受试者未检出糖尿病视网膜病变。
结论：便携式视网膜照相机联合远程医疗可作为糖尿病视网膜病变筛查与诊断的传统方法的高效替代方案。