Diabetic Retinopathy

Diabetic retinopathy is an eye disease that occurs as a consequence of diabetes mellitus. Persistently elevated blood sugar levels damage the fine blood vessels of the retina and, if untreated, can lead to significant vision loss up to and including blindness. It is one of the most common causes of visual impairment in working-age adults worldwide.

Diabetes Mellitus: What it is

Diabetes mellitus is a metabolic disease in which the body cannot properly regulate blood sugar. The main types are:

  • Type 1: Usually occurs in children and adolescents. The pancreas no longer produces insulin.
  • Type 2: More common in adulthood and often associated with overweight. The body cannot use available insulin effectively.
  • Gestational diabetes: Develops during pregnancy and usually resolves after birth.

High blood sugar levels damage blood vessels throughout the body — including the particularly sensitive vessels of the retina.

How Does Diabetic Retinopathy Develop?

The small blood vessels of the retina are especially sensitive to fluctuations and elevated blood sugar levels. Initially, the vessel walls become permeable, leading to small bleedings and fluid accumulation in the retina. As the disease progresses, vessels can close, depriving parts of the retina of adequate oxygen supply. In response, the body forms new but inferior-quality blood vessels that can easily burst and cause larger bleedings.

Stages

Non-Proliferative Diabetic Retinopathy (NPDR)

In the early stage, small vessel outpouchings (microaneurysms), dot-shaped bleedings, and protein deposits (hard exudates) are found in the retina. Many patients notice no vision changes at this stage.

Diabetic Macular Edema

Fluid accumulates in the area of the macula (the site of sharpest vision). This leads to blurred or distorted vision and is the most common cause of vision deterioration in diabetes.

Proliferative Diabetic Retinopathy (PDR)

New, unstable blood vessels grow into the retina or vitreous body. These can bleed and form scars that, in the worst case, cause retinal detachment.

Other Eye Problems in Diabetes

In addition to retinopathy, diabetes increases the risk of:

  • Cataract (gray star): Lens opacities occur earlier and more frequently in diabetics
  • Glaucoma (green star): Elevated intraocular pressure
  • Temporary visual fluctuations: Blood sugar fluctuations can temporarily deform the lens
  • Eye muscle palsies: Circulatory disorders of the cranial nerves can lead to double vision

Diagnosis

Diabetic retinopathy is detected through examination of the fundus with dilated pupils. Imaging procedures complement this:

  • OCT (Optical Coherence Tomography): Shows fluid accumulations and thickening of the retina
  • Fluorescein angiography: Makes leaking or closed vessels visible

Treatment

Optimal Blood Sugar Control

The most important measure is consistent control of blood sugar, blood pressure, and blood lipids. Studies show that good metabolic control can significantly slow the progression of retinopathy.

Intravitreal Injections

For macular edema, medications (anti-VEGF preparations or steroids) are injected directly into the vitreous body of the eye. They inhibit the growth of pathological vessels and reduce swelling.

Laser Treatment

Targeted laser coagulation can seal leaking vessels and slow the growth of new, unstable vessels.

Surgical Procedures

In advanced cases with vitreous hemorrhage or retinal detachment, vitrectomy (surgical removal of the vitreous body) may be necessary.

Prevention and Early Detection

Because diabetic retinopathy progresses without symptoms for a long time, regular ophthalmological examinations are essential:

  • Type 1 diabetes: First eye examination no later than five years after diagnosis, then at least annually
  • Type 2 diabetes: Eye examination at diagnosis, then at least annually
  • Gestational diabetes or pregnancy with existing diabetes: Close monitoring as recommended by the ophthalmologist

Our Advice

If you or your child has diabetes, attend the recommended eye examinations, even if vision seems good. The earlier changes to the retina are detected, the better the treatment options. Close cooperation between the primary care physician or diabetologist and the ophthalmologist is crucial.