Introduction  

Proliferative diabetic retinopathy is an eye disorder that occurs when there’s an abnormal vascular growth in the retina. It is a serious condition that threatens vision if not attended to.
 
Without proper management of diabetes, patients will usually suffer a myriad of problems. Proliferative diabetic retinopathy is just one of them. The condition starts asymptomatically at the earlier stage known as the non-proliferative phase. This is where small protrusions develop on the walls of the retinal blood vessels (microaneurysms). The swelling may leak fluid into the retina distorting vision. 

As the disease progresses, the vessels become damaged, and blood supply to the retina is cut short. The body responds by triggering proliferation of new blood vessels. Being fragile, the new vessels bleed easily and leak blood to other parts. Some complications can arise from here if the patient does not seek treatment early.

Also Known As

Advanced diabetic retinopathy

Causes and Risk Factors

Diabetic patients suffer damage to the retinal blood vessels due to the high sugar level in the blood. The sugar blocks the tiny blood vessels and distorts regular supply to the retina. Among the patients, risk factors for proliferative retinopathy include:

  • High cholesterol levels
  • Genetic predisposition
  • Longer duration of diabetes - Patients who’ve had diabetes for a long while are at a higher risk of contracting retinopathy.
  • Poor regulation of blood sugar - Diabetics who don’t adhere to treatment will more likely suffer from eye problems compared to those who do.
  • Hypertension - Having high blood pressure makes it harder for diabetic patients. The condition increases the risk for retinopathy.
  • Type 1 diabetes - Majority of the patients with the eye condition suffer from Type 1 diabetes.
  • Age - The condition is more apparent in individuals over 40 years.

Signs & Symptoms

Although there are usually no symptoms in the earlier non-proliferative stage, they begin to show in the proliferative phase. Patients present symptoms such as:

  • Blurred vision
  • Blindness
  • Blank spots in vision
  • Floaters (dark strings or spots in vision)

Diagnosis

To diagnose proliferative retinopathy, the eye professional will need to carry out a comprehensive exam. It may include tests such as:

  • Dilated eye exam - Dilator drops are used to enable proper viewing of the inside of the eyes. The growth of new blood vessels will indicate proliferative diabetic retinopathy.
  • Fluorescein angiography - It is done to pinpoint the specific blood vessels that are leaked or closed.
  • Fundus photography - Images are taken for documentation of the state of the retina
  • Visual acuity test - This is done to check for defects in the patient’s vision. Distorted vision is an indicator that the disease has progressed. 
  • Tonometry - The test is used to measure the pressure inside the eyes. Elevated pressure may result in glaucoma.
     

Treatment 

Treatment is aimed at inhibiting further growth of the abnormal vessels. It also focuses on preventing the eventual loss of vision.

Medical Treatment

The Anti-Vascular endothelial growth factor (Anti- VEGF) injection, mostly used in the non-proliferative phase can also be used in the proliferative stage to slow progression. The drug inhibits the work of the vascular endothelial growth factor. This is the hormone that promotes the proliferation of new blood vessels.

Surgical Treatment

  • Photocoagulation - This is a laser surgery therapy. The laser burns work to seal the leaking blood vessels. They also prevent bleeding by other vessels.
  • Vitrectomy - This is a surgical procedure that involves removal of the vitreous gel at the center of the eye. It is done in cases where there is severe blood leaking into the vitreous. After the surgery, the eye is covered with a patch for up to weeks. Drops can be used to ease inflammation and to prevent infection.

 

Prognosis/Long-term outlook

Proliferative diabetic retinopathy, if not treated early enough will result in many complications. These include:

  • Macular edema - This is where the retinal fluid leaks into the macula and causes it to swell.
  • Vitreous hemorrhage - With the new blood vessels leaking, blood can get its way into the vitreous space. The bleeding is responsible for the dark floaters that individuals see in the vision. The blood can, in some instances, fill the whole space and completely block vision.
  • Retinal detachment - Scar tissues may form with abnormal blood vessel growth. The tissues can detach the retina from the back.
  • Glaucoma - The blood vessel growth interferes with normal eye fluid drainage. It causes pressure to rise to levels that may damage the optic nerve. The result is a condition referred to as glaucoma.
  • Blindness - Due to complications, such as glaucoma, proliferative diabetic retinopathy can eventually lead to blindness.
     

Prevention/Follow Up

Individuals with diabetes can take the following preventive measures:

  • Sticking to recommended diet and lifestyle
  • Adhering to their prescribed medication
  • Exercising regularly
  • Regulating blood pressure
  • Avoiding cigarettes/alcohol
  • Monitoring vision by screening frequently