Introduction  

Diabetic retinopathy is an eye condition that occurs when there is damage to the retinal blood vessels due to type 1 or 2 diabetes. The disorder appears asymptomatic in its early stages, at the non-proliferative stage. However, a number of symptomatic complications may arise when there is no intervention.
The disease will usually progress to the advanced stage without showing any symptoms. Therefore, individuals may find out about it when the damage is severe.
At the non-proliferative stage, blockage of the tiny vessels of the retina occurs, followed by protrusion of tiny bulges known as microaneurysms from the walls. Blood and fluid may seep from these balloon-like formations and find their way to the retinal tissue.
After vascular damage, the supply to the retina is completely closed off and the growth factor is now stimulated to create new vessels (proliferative stage). The vessels grow abnormally and fail to develop properly. Due to their fragile nature, they leak blood into the vitreous gel, what is referred to as vitreous hemorrhage. At this stage, further problems may arise and lead to blindness.

Also Known As

Diabetic eye disease (DED)

Sub-Types

There are two major subtypes of diabetic retinopathy based on the severity of the disease. These are:

  • Non-proliferative diabetic retinopathy (NPDR)

It is the earliest phase of the disease, usually asymptomatic.

  • Proliferative diabetic retinopathy

This is the stage at which the disease has progressed significantly. It involves abnormal blood vessel growth.

Causes and Risk Factors

The damage to the retina in diabetic patients occurs due to high sugar levels in the blood. This results in blockage of the tiny vessels that supply the retina and eventually, leakage of fluids and blood. The factors that increase the risk of developing diabetic retinopathy include:

  • The severity of the disease
  • Those in the advanced stage of diabetes are more likely to develop retinopathy
  • High blood pressure
  • Pregnancy
  • Smoking
  • High cholesterol levels
  • Poor blood sugar regulation
     

Signs & Symptoms

As the disease advances, symptoms may include:

  • Floaters ( dark strings or spots that float in vision)
  • Blank or dark areas in vision
  • Blurred images
  • Poor night vision
  • Impaired color vision
     

Diagnosis

A comprehensive eye exam by an eye care professional can be used to diagnose diabetic retinopathy. The tests can comprise of:

  • An optical coherence tomography (OCT)
  • Fluorescein angiography
  • Tonometry
  • Dilated eye test
  • Visual acuity testing

The diagnosis is aimed at checking for changes in blood vessels, edema, leakages and damage to the optic nerve tissues.

Treatment 

Treatment of diabetic retinopathy is aimed at managing diabetes and preventing complications.

Medical Treatment

Usually, doctors will monitor the progress of the disease before prescribing any medication. Depending on the severity and type, the condition may resolve with proper sugar level control. In other cases an anti-VEGF injection may be administered to prevent abnormally blood vessel growth.

Surgical Treatment

Surgical procedures that can be carried out include the focal macular laser surgery which helps to reduce swelling and scatter surgery which causes the abnormal blood vessels to shrink. The vitrectomy is also another procedure conducted in cases of severe bleeding.

Prognosis/Long-term outlook

Symptoms of diabetes retinopathy may go away with sugar level control and proper adherence to diabetes treatment. However, without good management, the disease is likely to progress and cause complications such as vitreous hemorrhage, detachment of the retina, glaucoma and eventually, blindness.

Prevention/Follow Up

Patients can prevent retinopathy by managing their diabetes well, monitoring blood sugar levels, and regular eye check-ups (at least annually). Those already diagnosed should also visit eye care providers frequently to prevent further complications.