Difference Between Proliferative and Nonproliferative Retinopathy

The key difference between proliferative and nonproliferative retinopathy is that proliferative retinopathy refers to the presence of neovascularization (abnormal blood vessel growth) in the retina in diabetic retinopathy, while nonproliferative diabetic retinopathy refers to early diabetic retinopathy disease without neovascularisation.

The later stages of diabetic retinopathy are known as proliferative diabetic retinopathy (PDR). In this stage, abnormal blood vessels and scar tissue grow on the surface of the retina. They attach strongly to the back surface of the vitreous, which is the jelly-like substance that fills the centre of the eye. The vitreous then pulls on the scar tissue, and that causes the blood vessels to bleed into the vitreous cavity. This event is called vitreous hemorrhage. This will repeatedly happen in proliferative diabetic retinopathy and finally can cause immediate and severe visual loss. But often, these hemorrhages will clear by themselves. The most common and earliest stage of diabetic retinopathy is known as non-proliferative diabetic retinopathy (NPDR). In the early stages of diabetic retinopathy involves edema and leaking of hard exudates from abnormal blood vessels in the central retina, which ultimately results in blurred central vision. Later, further restriction of blood supply to the retina (vascular occlusion) occurs, together with an increase in macular edema.

CONTENTS

1. Overview and Key Difference
2. What is Proliferative Retinopathy
3. What is Nonproliferative Retinopathy
4. Similarities Between Proliferative and Nonproliferative Retinopathy
5. Side by Side Comparison – Proliferative vs Nonproliferative Retinopathy in Tabular Form
6. Summary

What is Proliferative Retinopathy?

The more severe form of diabetic retinopathy is called proliferative diabetic retinopathy. In this type of retinopathy, damaged blood vessels close off. This causes the abnormal formation of new blood vessels in the retina. These abnormal blood vessels leak into the vitreous, which is the jelly-like substance that fills the centre of the eye.

Eventually, the scar tissue stimulated by the growth of new abnormal blood vessels causes the retina to detach from the back of the eye. The new blood vessels may also interfere with the fluid flow out of the eye. As a result, the pressure in the eyeball increases. This can damage the optic nerve that carries images from the eye to the brain, causing glaucoma. The treatments for proliferative diabetic retinopathy are laser treatment, eye injections, and eye surgery.

What is Nonproliferative Retinopathy?

Nonproliferative retinopathy was previously called background retinopathy. It is the earliest form of diabetic retinopathy. In nonproliferative retinopathy, microscopic changes occur in the blood vessels of the eye. Anyhow, these changes do not produce typical symptoms. Nonproliferative disease progresses from mild to severe stages.

Nonproliferative diabetic retinopathy is initially characterized by microaneurysms. Microaneurysm is characterized by blood-filled bulges in the artery walls. These blood-filled bulges may burst and leak into the retina. Tiny spots filled with blood may accumulate in the retina. But they do not produce noticeable symptoms in the early stages of the disease. Later, hard exudates accumulation in the central retina, abnormalities in the growth of microscopic blood vessels in the retina, and bleeding from the veins may occur. Regular monitoring is the treatment for nonproliferative diabetic retinopathy. However, following doctors’ advice for diet, exercises, and controlling blood sugar level may improve the situation.

What are the Similarities Between Proliferative and Nonproliferative Retinopathy?

• Both are stages of diabetic retinopathy.
• They cause damages to the retina.
• Both may cause vision impairment.

What is the Difference Between Proliferative and Nonproliferative Retinopathy?

Proliferative retinopathy refers to the presence of neovascularization (abnormal blood vessel growth) in the retina in later stages of diabetic retinopathy. On the other hand, early diabetic retinopathy disease without neovascularization is called nonproliferative diabetic retinopathy. So, this is the key difference between proliferative and nonproliferative retinopathy. Moreover, proliferative retinopathy is characterized by severe symptoms such as the growth of abnormal new blood vessels and glaucoma. Meanwhile, In nonproliferative retinopathy, microscopic changes occur in the blood vessels of the eye. But these changes do not produce typical symptoms. Thus, this is also a difference between proliferative and nonproliferative retinopathy.

Below is a summary of the differences between proliferative and nonproliferative retinopathy in tabular form.

Summary – Proliferative vs Nonproliferative Retinopathy

Proliferative and nonproliferative retinopathy are stages of diabetic retinopathy. Proliferative retinopathy refers to the presence of neovascularization (abnormal blood vessel growth) in the retina in the later stage of diabetic retinopathy. Early diabetic retinopathy disease without neovascularization is called nonproliferative diabetic retinopathy. Both types may cause vision impairment if they are not regulated properly. Thus, this summarizes the difference between proliferative and nonproliferative retinopathy.

Reference:

1. “Diabetes Symptoms: Non-Proliferative Retinopathy Information: MyVMC.” HealthEngine Blog, 4 July 2011, Available here.
2. “Diabetic Retinopathy.” Mayo Clinic, Mayo Foundation for Medical Education and Research, 30 May 2018, Available here.

Image Courtesy:

1. “Proliferative diabetic retinopathy” By Community Eye Health (CC BY-NC 2.0) via Flickr
2. “Mild non-proliferative retinopathy.” By Community Eye Health (CC BY-NC 2.0) via Flickr