Aims: To present an authoritative, universal, easy-to-use morphologic classification of diabetic maculopathy based on spectral domain optical coherence tomography. Methods: The first draft of the project was developed based on previously published classifications and a literature search regarding the spectral domain optical coherence tomography quantitative and qualitative features of diabetic maculopathy. This draft was sent to an international panel of retina experts for a first revision. The panel met at the European School for Advanced Studies in Ophthalmology headquarters in Lugano, Switzerland, and elaborated the final document. Results: Seven tomographic qualitative and quantitative features are taken into account and scored according to a grading protocol termed TCED-HFV, which includes foveal thickness (T), corresponding to either central subfoveal thickness or macular volume, intraretinal cysts (C), the ellipsoid zone (EZ) and/or external limiting membrane (ELM) status (E), presence of disorganization of the inner retinal layers (D), number of hyperreflective foci (H), subfoveal fluid (F), and vitreoretinal relationship (V). Four different stages of the disease, that is, early diabetic maculopathy, advanced diabetic maculopathy, severe diabetic maculopathy, and atrophic maculopathy, are based on the first four variables, namely the T, C, E, and D. The different stages reflect progressive severity of the disease. Conclusion: A novel grading system of diabetic maculopathy is hereby proposed. The classification is aimed at providing a simple, direct, objective tool to classify diabetic maculopathy (irrespective to the treatment status) even for non-retinal experts and can be used for therapeutic and prognostic purposes, as well as for correct evaluation and reproducibility of clinical investigations.

Our measurement showed significantly decreased flow velocities in the retinal arterioles and venules of patients with diabetes compared with healthy control subjects, supporting the view of abnormal vessel function in eyes with nonproliferative diabetic retinopathy.

Retinal disease management has witnessed remarkable advances in posterior segment pharmacotherapy with the development of anti-VEGF molecules such as Lucentis® (ranibizumab), Eylea® (aflibercept), and off-label bevacizumab (Avastin). The US patents for ranibizumab and aflibercept will expire in 2020 (though Regeneron has indicated that it might attempt to extend its US patent to June 2023 with additional patent claims), and their European patents will expire in 2022 and 2025. Aflibercept comes off patent in 2022 in People’s Republic of China and Japan. As soon as each patent expires, biosimilar molecules could potentially come in the mainstream clinical practice as a more cost-efficient choice in the form of generic biosimilars. It is difficult to predict how significant this shift would be in terms of more cost-effective clinical management and how it will impact the care in developed and developing world. It is important for clinicians to have a clear understanding about ophthalmic biosimilars before the industry brings these molecules to the mainstream clinical use globally.

There was an increase in arterial and venous retinal blood flow velocities of patients with early DM with no diabetic retinopathy. These findings support the notion that abnormalities in vessel function exist in diabetic eyes before the development of structural changes. This noninvasive approach facilitated the assessment of early hemodynamic abnormalities and may assist in screening and monitoring.