Documenta Ophthalmologica

, Volume 124, Issue 1, pp 15–26 | Cite as

The pathogenesis of early retinal changes of diabetic retinopathy

  • G. B. ArdenEmail author
  • S. Sivaprasad
Review Article


Recent successful trials of antibodies to vascular endothelial growth factor (VEGF) in diabetic retinopathy implicate this cytokine as a major cause of diabetic retinopathy (DR) and diabetic macular oedema (DME). The mechanisms which cause VEGF to be over-expressed to cause the vasculopathy are not entirely clear. This review explores the earliest changes to the retina in DR and the factors that predispose or prevent DR, including sleep apnoea, receptor degenerations laser treatment and VEGF polymorphism. The review also presents the evidence that retinal hypoxia, existing in the earliest stages, causes DR. This hypoxia is much increased by dark adaptation, indicating a new and possibly superior therapy.


Diabetic retinopathy Rods Dark adaptation VEGF Oxidative stress hypoxia 


Conflict of interest

G.B. Arden has a commercial relation with KeepSight Ltd, who intend to manufacture lightmasks.


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Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  1. 1.City University LondonLondonUK
  2. 2.Kings College Hospital NHS Foundation TrustLondonUK

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