Telemedicine screening of retinal diseases with a handheld portable non-mydriatic fundus camera

Abstract

BackgroundWe modified and reconstructed a high image quality portable non-mydriatic fundus camera and compared it with the tabletop fundus camera to evaluate the efficacy of the new camera in detecting retinal diseases.MethodsWe designed and built a novel portable handheld fundus camera with telemedicine system. The image quality of fundus cameras was compared to that of existing commercial tabletop cameras by taking photographs of 364 eyes from the 254 patients. In all 800 fundus images taken by two camera types, 400 images per camera, were graded with the four image clarity classifications.ResultsUsing the portable fundus camera, 63% (252/400) images were graded as excellent overall quality, 20.5% (82/400) were good, 11.75% (47/400) were fair, and 4.75% (19/400) were inadequate. Using the tabletop fundus camera, 70.75% (283/400) images were graded as excellent overall quality, 20.4% (51/400) were good, 13.25% (53/400) were fair, and 3.25% (13/400) were inadequate. Common retinal diseases were easily identified from fundus images obtained from the portable fundus camera.ConclusionThe new type of non-mydriatic portable fundus camera was qualified to have professional quality of fundus images. The revolutionary screening camera provides a foundational platform which can potentially improve the accessibility of retinal screening programmes.

Diagnostic Test Accuracy of Diabetic Retinopathy Screening by Physician Graders Using a Hand-held Non-Mydriatic Retinal Camera at a Tertiary Level Medical Clinic

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“…Some defined the cup margin at specific depths from the disc margin such as 150 and 120 μm. Others defined the margin as a proportion of the total cup depth such as one‐fifth, one‐third and one‐half . One group used a hybrid approach defining the cup margins as 150 μm depth while using one‐fifth depth for especially shallow or deep cups (<0.2 or >1.0 mm) .…”

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New open source 3-dimensional printed smartphone fundus imaging adaptor

“…The recent development of portable fundus imaging systems has enabled greater access to disease screening, monitoring, and documentation in resource-poor situations and reduced the level of expertise required for the user. 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.…”