Diabetic retinopathy develops in 35-50% of diabetic patients. Depending on the duration of diabetes, diabetic retinopathy develops with 10 years of diabetes in 20%, 20 years in 60%, and 30 years in 90%. The main risk factors are duration of diabetes mellitus, high level of glycemia, arterial hypertension

Pathogenesis of diabetic retinopathy

 Microcirculatory abnormalities related to the systemic disease include three main pathogenetic factors: vascular wall lesions, altered blood flow, impaired platelet function

- These factors underlie the pathological changes in diabetic retinopathy such as exudation through altered vessel walls, retinal ischemia due to capillary damage and occlusion. Ischemia leads to increased concentrations of vascular endothelial growth factor - VEGF factor. VEGF-A plays a major role in the development of neovascularization: it triggers endothelial cell proliferation, regulates their migration and prevents apoptosis, causes abnormal vascular permeability and subsequent edema changes in the affected tissues, stimulates pathological growth of new fragile blood vessels in the eye.

In retinal diseases associated with neovascularization, levels of VEGF and PGF, which contributes to abnormal vessel formation and inflammation, thus mediating the development of macular edema. Hyperglycemia, changes in the vascular wall, retinal ischemia lead to changes in type II collagen, cross linking (sticking) of collagen fibrils, thickening and contraction of collagen fibers, liquefaction of the vitreous body (synchisis and syneresis of VB), development of abnormal posterior vitreous detachment, and subsequently tractional retinal detachment

American Diabetes Association (2000)

- Diabetic retinopathy 0

- Nonproliferative diabetic retinopathy a (initial stage)

- Nonproliferative diabetic retinopathy b (middle stage nonproliferative DR)

- Nonproliferative diabetic retinopathy c (severe stage of nonproliferative DR)

- Proliferative diabetic retinopathy b (proliferative diabetic retinopathy)

WHO classification  (Kohner E. Porta M. (1991 ?)

Nonproliferative, Preproliferative, Proliferative Diabetic Retinopathy.

Depending on the localization and height of retinal detachment P. Kroll 1987 proposed a classification of proliferative diabetic vitreoretinopathy (stages A,B,C).

Depending on the stage of diabetic retinopathy different types of treatment are used at the present stage. At the preproliferative and proliferative stages, retinal laser photocoagulation, anti-VEGF therapy or their combinations are used. The presence of macular edema is an indication for intravitreal injection of anti-VEGF drugs. With the development of proliferative vitreoretinopathy, hemophthalmos, tractional retinal detachment, vitreoretinal surgical intervention is applied.  Different methods of treatment and their results will be demonstrated in the report.