Diabetic Retinopathy

Diabetic retinopathy is a progressive ophthalmic condition that is associated with diabetes and can have devastating consequences. It is a leading cause of blindness in adults of working age and is characterised by capillary leakage, capillary vessel occlusion and subsequent new vessel formation.
It can be broadly classified as:

  • non-proliferative diabetic retinopathy that is characterised by microaneurysms, haemorrhages, exudates, intraretinal microvascular abnormalities (IRMA), venous beading and clinically significant macular oedema
  • proliferative retinopathy that is defined growth of abnormal new vessels on the retina, on the optic disc or into the vitreous cavity, in addition to lesions described under non-proliferative retinopathy.

Duration of diabetes is a major risk indicator associated with the development of retinopathy. Retinopathy will develop within 5 years of diagnosis of diabetes in approximately:

  • 25% of people with Type 1 diabetes (1)
  • 40% of people with Type 2 diabetes who are taking insulin (2)
  • 24% of people with Type 2 diabetes who are not taking insulin (2).

There are currently three evidence-based approaches with long-term effects on the progression of retinopathy in patients with diabetes (glycaemic control, anti-hypertensive therapy and laser photocoagulation treatment).

Diabetic macular oedema is a separate manifestation of  non-proliferative retinopathy, characterised by oedema, hard exudates (lipoprotein deposits) and microaneurysms located in the macular area.

References
  1. Klein R, Klein BEK, Moss SE, et al. The Wisconsin Epidemiological Study of Diabetic Retinopathy. II. Prevalence and risk of diabetic retinopathy when age at diagnosis is less than 30 years. Arch Ophthalmol 1984;102:520–526.
  2. Klein R, Klein BEK, Moss SE, et al. The Wisconsin Epidemiological Study of Diabetic Retinopathy. III. Prevalence and risk of diabetic retinopathy when age at diagnosis is 30 or more years. Arch Ophthalmol 1984;102:527–532.