Approach for a Clinically Useful Comprehensive Classification of Vascular and Neural Aspects of Diabetic Retinal Disease

Abstract

The Early Treatment Diabetic Retinopathy Study (ETDRS) and other standardized classification schemes have laid a foundation for tremendous advances in the understanding and management of diabetic retinopathy (DR). However, technological advances in optics and image analysis, especially optical coherence tomography (OCT), OCT angiography (OCTa), and ultra-widefield imaging, as well as new discoveries in diabetic retinal neuropathy (DRN), are exposing the limitations of ETDRS and other classification systems to completely characterize retinal changes in diabetes, which we term diabetic retinal disease (DRD). While it may be most straightforward to add axes to existing classification schemes, as diabetic macular edema (DME) was added as an axis to earlier DR classifications, doing so may make these classifications increasingly complicated and thus clinically intractable. Therefore, we propose future research efforts to develop a new, comprehensive, and clinically useful classification system that will identify multimodal biomarkers to reflect the complex pathophysiology of DRD and accelerate the development of therapies to prevent vision-threatening DRD.

Figure

Dimension or axes in classification systems for diabetic retinopathy. Left: Current two-dimensional classification systems such as ETDRS, ICDR, and Eurodiab use two axes, one for diabetic macular edema (DME) severity and one for diabetic retinopathy (DR) proper (from no DR to proliferative DR [PDR]). In such a system, a patient can have extensive DME without any microaneurysms or hemorrhages. Right: Potential three-dimensional classification that includes estimated DRN damage in addition to the familiar two axes. In such a system, a patient can have extensive DME without any microaneurysms or hemorrhages, and early DRN.