Diabetic Retinopathy

Many patients with diabetes especially those with poorly controlled blood glucose have damaged vessels at the retina. This is called diabetic retinopathy. It affects 80% of patients who have diabetes for at least 10 years. All asymptomatic patients with diabetes are advised to have an annual dilated ophthalmic examination of their retinas to screen for diabetic retinopathy.

To prevent the onset of diabetic retinopathy one should ensure good control of the blood sugar, blood pressure and cholesterol. This can be achieved following advice from nutritionists, general practitioners and diabetologists.

Many people with mild diabetic retinopathy (non proliferative diabetic retinopathy) have good vision, but there are two types of sight-threatening diabetic retinopathy: diabetic macular oedema (DMO) and proliferative diabetic retinopathy (PDR)

Proliferative Diabetic Retinopathy (PDR)

Proliferating diabetic retinopathy occurs when the retinal vessels close and the retina becomes ischaemic (starved of blood and oxygen). As a result, abnormally fragile vessels develop on the surface of the retina. These vessels can lead to loss of vision secondary to bleeding into the eye, scarring or retinal detachment. The main treatment for PDR remains the laser. Anti-VEGF injections may be added as an adjuvant treatment.

Diabetic macular oedema (DMO)

Diabetic macular oedema if fluid collection that results from leaky damaged retinal vessels. It usually concentrates at the macula, the area responsible for the central detailed vision. The accumulation of fluid (oedema) leads to blurred vision. If this is left untreated, the patients will not be able to drive and will lose central vision. The peripheral vision is usually not affected from the oedema. The mainstay of DMO treatment is in the form of anti-VEGF injections to the eye. The VEGF antibodies injected reduce the fluid leakage from the damaged vessels. Laser therapy may be applicable in certain situations.

Normal macular OCT

Diabetic macular oedema at the macula OCT

How shall I reduce the risk of diabetic retinopathy?

Regular eye checks are essential for all the patients with diabetes. If diabetic retinopathy is detected and treated early, the vision is likely to remain stable. To prevent the onset of diabetic retinopathy one should ensure good control of the blood sugar, blood pressure and cholesterol. This can be achieved following advice from nutritionists, general practitioners and diabetologists.

Related Articles

• Diabetic Retinopathy: Causes, Symptoms, Treatment (American Academy of Ophthalmology)
• Understanding eye conditions related to diabetes (Royal National Institute of Blind People - RNIB)