Department of Chronic Disease Epidemiology, Yale School of Public Health, New Haven, CT.
Department of Ophthalmology, Lahey Hospital & Medical Center, Burlington.
J Glaucoma. 2021 Jan 1;30(1):58-60. doi: 10.1097/IJG.0000000000001680.
Evaluation of nonmydriatic fundus photographs captured with a low-cost, smartphone-based camera facilitated remote screening of patients for enlarged optic nerve cup-to-disc ratio in the Independent Nation of Samoa, an underserved setting with one full-time ophthalmologist in the entire country.
To investigate factors that impact inter-rater agreement of glaucoma suspect optic disc status using a low-cost, handheld nonmydriatic fundus camera.
Color fundus photographs were obtained using the PanOptic iExaminer attached to an iPhone 6S by a lay examiner on 206 participants in the Independent Nation of Samoa. Images were remotely graded by an ophthalmologist and optometrist, and images from participants identified as at-risk for glaucoma were escalated to a glaucoma subspecialist for review. Fundus photo brightness, contrast, and focus were measured using the cup, rim, and temporal regions of the disc. Stereoscopic image pairs were subsequently generated from a subset of individual nonmydriatic photographs.
Features suggestive of glaucoma based on optic disc cupping were identified in 16.0% (33/206) of participants. There was moderately strong agreement between graders (90.3%) with κ=0.53 [95% confidence interval (CI)=0.33-0.73]. The intraclass correlation coefficients for the cup-to-disc ratio (CDR) and its difference were 0.84 (95% CI=0.81-0.87) and 0.68 (95% CI=0.59-0.75). Of the 33 participants identified, 94% had clinical risk criteria for potential glaucoma when reviewed by a subspecialist. Color fundus photograph cup brightness was significantly associated with cup-to-disc (CDR) grade, R2=0.36 (P<0.001), in which a brighter disc yielded a higher CDR.
Smartphone-based screening is a simple, low-cost method capable of measuring the CDR of the optic nerve. When combined with testing for other glaucoma risk factors such as intraocular pressure, this method of measuring CDR may help identify those patients who should be referred for further ophthalmologic assessment. We are currently conducting studies to assess the sensitivity and specificity of smart phone-based remote screening.
在萨摩亚独立国（一个全国只有一位全职眼科医生的服务不足地区），使用低成本的智能手机眼底相机对患者进行视神经杯盘比增大的远程筛查，评估了非散瞳眼底照片的效果。
研究使用低成本手持式非散瞳眼底相机影响青光眼疑似视神经盘状态的分级观察者间一致性的因素。
由一位非专业检查者使用 PanOptic iExaminer 连接 iPhone 6S 对 206 名萨摩亚独立国的参与者进行眼底彩照拍摄。由一名眼科医生和验光师进行远程分级，将被识别为青光眼高危的参与者的眼底照片升级给青光眼专家进行复查。使用视盘的杯、边缘和颞部测量眼底照片的亮度、对比度和焦点。从眼底照片中随机选择一部分生成立体图像对。
在 16.0%（206 名参与者中的 33 名）参与者中发现了基于视盘凹陷的青光眼特征。分级者之间的一致性较强（90.3%），κ=0.53[95%置信区间（CI）=0.33-0.73]。杯盘比（CDR）及其差值的组内相关系数分别为 0.84（95%CI=0.81-0.87）和 0.68（95%CI=0.59-0.75）。在被识别的 33 名参与者中，当由专家进行复查时，94%的参与者有潜在青光眼的临床风险标准。彩色眼底照片的视盘亮度与杯盘比（CDR）分级显著相关，R2=0.36（P<0.001），其中视盘越亮，CDR 越高。
基于智能手机的筛查是一种简单、低成本的方法，能够测量视神经的 CDR。当与眼压等其他青光眼危险因素测试相结合时，这种 CDR 测量方法可能有助于识别那些需要进一步眼科评估的患者。我们目前正在进行研究，以评估基于智能手机的远程筛查的敏感性和特异性。
