Validation of Smartphone-Based Retinal Photography for Diabetic Retinopathy Screening

Abstract

BACKROUND AND OBJECTIVE: Screening for diabetic retinopathy (DR) is cost-effective when compared with disability loss for those who go blind in the absence of a screening program. We aimed to evaluate the sensitivity and specificity of a smartphone-based device for the screening and detection of DR. PATIENTS AND METHODS: A cross-sectional study of 220 patients with diabetes (440 eyes, all patients age 25 years or older) was completed. Tropicamide 0.5% was used for iris dilation followed by an indirect ophthalmoscopy using a 20-D lens. Retinal images were later obtained using a smartphone attached to an adaptable camera device. Retinal images permitted the visualization of the macular and papillary regions and were sent without compression via the internet to a retinal specialist for interpretation. Sensitivity and specificity were calculated for all cases and stages of DR. RESULTS: Using our standard examination method, the prevalence of DR and macular edema were 13.6% and 6.4%, respectively. With the smartphone-based retinal camera, the prevalence of DR and macular edema were 18.2% and 8.2%, respectively. Sensitivity and specificity for the detection of all stages of DR was 73.3% and 90.5%, respectively. For the detection of macular edema, sensitivity was 77.8%, and specificity was 95%. For severe nonproliferative DR (NPDR), sensitivity and specificity were 80% and 99%, respectively; for proliferative DR (PDR), they were both 100%. In the early stages of DR, specificity was 89.8% for mild NPDR and 97.1% for moderate NPDR. Sensitivity was 57.1% and 42.9%, respectively. CONCLUSION: Screening for DR using a smartphone-based retinal camera has a satisfactory specificity at all DR stages. Its sensitivity seems to be high only in the stages of DR necessitating a specific therapeutic decision (eg, macular edema, severe NPDR, and PDR). A smartphone-based retinal camera may be a useful device to screen for DR in resource-limited settings. [ Ophthalmic Surg Lasers Imaging Retina . 2019;50:S18–S22.]

Screening for diabetic retinopathy: new perspectives and challenges

“…In addition, they are easy to use and have adequate levels of validated sensitivity and specificity and, therefore, their implementation appears both feasible and realistic. [78][79][80][81] Several studies show that eye diseases related to diabetes can be prevented through early detection and screening. Retinal evaluations help in the prevention of vision loss resulting from DR.…”

Comparison of Telemedicine Screening of Diabetic Retinopathy by Mydriatic Smartphone-Based vs Nonmydriatic Tabletop Camera-Based Fundus Imaging

“…Several other studies support the use of mydriatic smartphone-based fundus photography as a reliable and costeffective option to expand screening for DR. 11,[14][15][16]18,29,30 The prospective CAMRA (Comparison Among Methods of Retinopathy Assessment) study of 300 patients compared smartphone fundus photography after dilation and nonmydriatic fundus photography against reference standard 7field mydriatic fundus photography in their ability to detect and grade DR. 15 Tested in an outreach setting in India, detection of moderate NPDR or worse was comparable between mydriatic smartphone photography and nonmydriatic tabletop photography, with sensitivity of 59% (smartphone; 95% CI, 46%-72%) vs 54% (nonmydriatic; 95% CI, 40%-67%) and specificity of 100% (smartphone; 95% CI, 99%-100%) vs 99% (nonmydriatic; 95% CI, 98%-100%). Russo et al 14 prospectively compared mydriatic smartphone-based direct ophthalmoscopy to dilated slitlamp examination in the detection of DR in 120 patients with type 1 or type 2 diabetes and found exact agreement in 204 of 240 eyes (85%, k ¼ 0.78; CI, 0.71-0.84).…”

“…Bilong and colleagues, 29 in a cross-sectional study of 220 patients with diabetes, compared the detection of DR using a smartphone attached to an adaptable camera device with pupillary dilation in a teleophthalmology setting with DR detection using indirect ophthalmoscopy, and found the sensitivity and specificity for all stages of DR to be 73.3% and 90.5%, respectively. The sensitivity and specificity improved to 80% and 99%, respectively, for severe NPDR and to 100% for both in PDR.…”

Teleophthalmology and Artificial Intelligence As Game Changers in Ophthalmic Care After the COVID-19 Pandemic

“…It is estimated that 486 million people worldwide have DM and almost ⅓ suffers from DR while the visual-threatening cases are increasing according to Yau et al [ 27 , 28 ]. In this setting, teleophthalmological tools are essential for screening, management and follow up of DR. Retinal imaging is achieved with portable screening devices such as mobile imaging units, smartphone-based retinal photography and applications of AI providing high sensitivity and specificity [ 4 , 29 , 30 ]. Images are either evaluated by a remote ophthalmologist or automatically analyzed by a deep learning algorithm [ 31 ].…”