Predictors of Photographic Quality with a Handheld Nonmydriatic Fundus Camera Used for Screening of Vision-Threatening Diabetic Retinopathy

Abstract

Purpose: To analyze predictors of image quality for a handheld nonmydriatic fundus camera used for screening of vision-threatening diabetic retinopathy. Methods: An ophthalmic photographer at an Aravind Eye Hospital obtained nonmydriatic and mydriatic fundus images from 3 fields in 275 eyes of 155 participants over 13 months using a Smartscope camera (Optomed, Oulu, Finland) and a Topcon tabletop fundus camera (Topcon, Tokyo, Japan). Two fellowship-trained retina specialists graded the images. Repeated-measures logistic regression assessed predictors of the main outcome measure: gradability of the fundus images. Results: Of 2,475 images, 76.2% of the Smartscope nonmydriatic images, 90.1% of the Smartscope mydriatic images, and 92.0% of the Topcon mydriatic images were gradable. Eyes with vitreous hemorrhage (OR = 0.24, p < 0.0001) or advanced cataract (OR = 0.08, p < 0.0001) had decreased odds of image gradability. Excluding eyes with cataract or vitreous hemorrhage, nonmydriatic macular image gradability improved from 68.4% in the first set of 55 eyes to 94.6% in the final set of 55 eyes. Conclusion: With sufficient training, paraprofessional health care staff can obtain high-quality images with a portable nonmydriatic fundus camera, particularly in patients with clear lenses and clear ocular media.

Diabetic retinopathy screening in urban primary care setting with a handheld smartphone-based retinal camera

“…Diabetic retinopathy (DR) is a leading cause of severe visual loss which affects approximately 30 million individuals worldwide and can be prevented with timely screening, detection and treatment; however, even in high-income countries, access to yearly eye examinations is limited to only one-third to one-half of adults with diabetes, leaving a substantial number of patients at risk [1]. In the USA, only about 60% of people with diabetes have recommended yearly screenings for diabetic retinopathy; in some community-based studies, that rate is even lower [2]; in middle-to low-income countries, where access to ophthalmic care is generally limited, the rate of individuals with diabetes who have access to eye examinations is remarkably low [3].…”

“…Handheld cameras are increasingly available for diabetic retinopathy screening, having several advantages over traditional tabletop cameras, such as increased portability and decreased cost, with the potential of improving DR screening rates [1]. For optimal image quality, training in image acquisition and ocular media transparence are needed.…”

Diabetic Retinopathy Screening in Urban Primary Care Setting with a Handheld Smartphone-based Retinal Camera.

“…Visual loss secondary to diabetic retinopathy (DR), a leading cause of severe visual loss worldwide, can be prevented with timely screening, detection, and treatment; however, even in high-income countries, access to yearly eye examinations is limited, leaving a substantial number of patients at risk [1]. In middle to low income countries, the rate of individuals with diabetes who have access to eye examinations is remarkably low [2].…”

“…Hand-held cameras are increasingly available for diabetic retinopathy screening, having several advantages over traditional tabletop cameras, such as increased portability and decreased cost, with the potential of improving DR screening rates [1]. For optimal image quality, training in image acquisition and ocular media transparence are needed.…”

New open source 3-dimensional printed smartphone fundus imaging adaptor

“…1 Handheld fundus cameras such as the Optomed line of systems have shown good clinical value in several diseases in comparison to traditional desktop fundus cameras in clinics. 2,3 However, these systems cost approximately $10 000 to $14 000 each and require dedicated electronics, limiting their reach. In contrast, smartphones have been projected to reach 59% of the world's population by 2022.…”