Introduction  

Non proliferative diabetic retinopathy (NPDR) is an eye condition resulting from diabetes complications. It occurs because of the deterioration of retinal blood vessels.
NPDR is the most common form of diabetic retinopathy. It usually affects both eyes.
In this eye disorder, the retinal blood vessels become weak and may develop leaks. As a result, blood and fluid may leak into the retina. Also, hard exudates, a fatty matter, can be deposited in the retina causing it to swell. 
Where the swelling occurs in the macula, the middle of the retina, it’s known as macular edema. It can reduce vision or cause it to blur. Leakage in other parts of the retina usually doesn’t affect sight.
NPDR can often affect anybody with type 1 or type 2 diabetes. The less controlled a patient’s blood sugar is and the longer one has diabetes, the higher the risk of developing this eye complication.
Statistics show that after 20 years of diabetes, a vast majority of patients experience some degree of retinopathy.

Also Known As

NPDR

Sub-Types

  • Mild nonproliferative retinopathy

It is the earliest stage of the eye disease. Tiny swellings, called microaneurysms, develop in the retina’s blood vessels. These swellings may cause fluid to leak into the retina.

  • Moderate nonproliferative retinopathy

This stage is characterized by blot and dot hemorrhages, multiple microaneurysms, cotton wool spots and venous beading.

  • Severe nonproliferative retinopathy 

It also goes by the name high risk non proliferative diabetic retinopathy; it is the advanced level of NPDR. Areas of the retina deprived of blood supply secrete growth factors signaling it to grow new blood vessels.

Causes and Risk Factors

Non proliferative diabetic retinopathy occurs because of long periods of high glucose or blood sugar levels which damage blood vessels of the retina.
NPDR risk factors include:

  • Duration of diabetes which is the primary factor
  • Poor glycaemic control 
  • Race - Hispanics and African Americans are at higher risk 
  • An increase in cholesterol levels
  • Pregnant women are at a higher risk
  • Kidney impairment
  • Cataract surgery
  • Genetics
     

Signs & Symptoms

In the early stages, NPDR may have no symptoms or a patient may experience mild vision problems. 
In the advanced stages the symptoms may include:

  • Sudden onset of black or red strings or spots (floaters)
  • Blurred Vision
  • Reduced central vision
  • Distorted vision
  • Poor night vision
  • Vision loss
     

Diagnosis

The eye care professional conducts a slit lamp examination to diagnose non proliferative diabetic retinopathy. For a more comprehensive evaluation, the other methods may be used. These include: 

  • Fluorescein angiography (FA)
  • B-Scan ultrasound (B- Scan)
  • Optical coherence tomography (OCT)
  • Fundus photography (FP)

It enables the professional to detect:

  • Abnormalities in the optic nerve
  • Abnormal blood vessels
  • Retinal detachment
  • Blood or fatty deposits or swelling of the macula
  • Damaged nerve tissue and growth of new blood vessels  
  • Leaking blood vessels

He/she may also:

  • Test the patient’s vision
  • Check for evidence of cataracts
  • Measure eye pressure to test for glaucoma
     

Treatment 

Treatment aims at slowing or stopping the progression of the disease.

Medical Treatment

Treatment depends on the stage of NPDR. Patients with mild or moderate NPDR may not need treatment immediately. Usually, dietary interventions and medications are enough to control the condition. The eye care doctor monitors the patient’s eyes to determine when treatment is necessary. 

Moderate nonproliferative and severe nonproliferative retinopathy may need medications called anti-VEGF therapy before proliferation develops. These medications block the effects of growth signals that prompt the development of new blood vessels. 

Surgical Treatment

Photocoagulation or focal laser treatment may help to stop or slow blood and fluid leaking in the eye. The doctor uses laser burns to treat leaks from abnormal blood vessels. 

Panretinal photocoagulation or scatter laser treatment may help to shrink unusual blood vessels. 

Vitrectomy, a procedure that removes unwanted fluid from the eye and scar tissue on the retina. 

It is important to note that surgery doesn’t cure; it can only slow or stop the progression of the disease.

Home Care

Patients with NPDR should take adequate measures at home to control blood sugar, blood pressure and cholesterol. It cuts the chances of the disease progression. 

To this end, one should get at least 150 minutes of moderate exercise per week. Taking up the 10 000 step per day program is a great idea. A healthy diet is also critical. It is also important to avoid sugary and processed foods, smoking and excess alcohol intake.
 

Prognosis/Long-term outlook

In the long term, diabetes management is the key factor that determines the outcome of NPDR. Poor diabetes management encourages the non proliferative diabetic retinopathy to progress to the proliferative stage.
Even after treatment for NPDR, a patient will need regular eye check-ups. Diabetes is a lifelong condition, and at some point, more treatment for non proliferative diabetic retinopathy may be recommended.

Prevention/Follow Up

Diabetics should get regular eye exams even if their vision seems fine. Pregnant women should see an eye doctor about other eye check-ups throughout their pregnancy.

Getting early treatment and careful management of diabetes are the best ways to prevent the progression of the disease and vision loss.