Corneal opacity – what does that mean?

The cornea is a transparent layer of the human eye.
If the cornea is cloudy, vision is impaired.
In this article, you can find out how to recognize corneal clouding, what causes it and what treatment options are available.

What is corneal opacity?

The cornea lies above the pupil and the iris and consists of five different layers.
Each of these layers is transparent so that light can penetrate the eye undisturbed, resulting in clear vision.

The posterior layer has pump cells that control the exchange of aqueous humor in the eye.
If the function of the pump cells is impaired, too much aqueous humor enters the eye, causing swelling (oedema).
This leads to clouding of the cornea.
Clouding is also possible due to scarring of the cornea.

Consequences of corneal opacity

Due to corneal opacity, the transparency of the cornea is reduced and light transmission is impaired.
This causes the image to be projected onto the retina out of focus, resulting in blurred vision for those affected.

Causes of corneal opacity
There are several causes that lead to corneal opacity.
These include the following:

Injuries and inflammation of the cornea

If the cornea is injured, swelling (edema) can occur if the pump cells are damaged.
Corneal scars often form as a result of injuries, which also lead to clouding.

In addition, various bacteria, fungi and viruses (e.g. herpes viruses) can penetrate the cornea more quickly as a result of injuries and cause inflammation.
Inflammation increases the risk of corneal clouding.

Eye diseases

Eye diseases can also cause corneal opacity.
These include keratoconus (cone-shaped protrusion of the cornea) or Fuchs endothelial dystrophy, which is hereditary.

Corneal opacity after laser eye surgery

Corneal clouding can occur as a complication after laser eye surgery.
However, it is often only a slight clouding that can be treated with medication.

Metabolic disorders and autoimmune diseases

Finally, the cause of corneal opacities can be metabolic and autoimmune diseases.
This is possible in the following diseases, for example:

• Farber’s disease
• Fabry disease
• Stromal corneal dystrophy
• Sjögren’s syndrome

Symptoms of corneal opacity

Initially, corneal clouding is often noticeable through visual disturbances.
Those affected experience cloudy and blurred vision.
Blisters on the cornea are also possible.
These are perceived as painful.
If the blisters open, there is an increased risk of inflammation.
Other symptoms of corneal clouding are

• Light sensitivity
• Eye pain
• Foreign body sensation

The symptoms depend on the underlying cause of the opacity.
If the edema is not treated and progresses, corneal opacity may become visible.
The clouding leads to a visible white film on the eye – but this only occurs at an advanced stage, which can last for months or years.

How is corneal opacity diagnosed?

If corneal opacity is suspected, the cornea is first examined.
This is usually done using a slit lamp examination.
The patient places their head on a support.
The eye specialist can then use a microscope and a light source to examine the back of the eye and the cornea.
Even minor opacities and edema can be detected.

The cause of the corneal opacity can often also be identified during the slit lamp examination.
Inflammation and scarring also become visible.

Corneal opacity diagnosed – what treatment options are there?

Corneal opacity can usually be treated.
However, the exact treatment method depends on factors such as the cause and severity.

Drug treatment

If the corneal clouding is caused by inflammation, treatment with medication may be considered.
Eye drops containing cortisone are often used for this purpose.

Surgical intervention

Eye surgery (phototherapeutic keratectomy) is used if treatment with medication has not been successful or the corneal clouding has been caused by small injuries/scarring.
A laser is used to remove the scarring and clouding.
However, this is only possible if the uppermost layers of the cornea are affected.

Corneal transplantation

If the corneal clouding has progressed to such an extent that there is a risk of blindness, a corneal transplant (keratoplasty) is often the only promising treatment option.
In keratoplasty, the cloudy cornea is removed and a donor cornea is inserted.

Prevent corneal opacity

Corneal opacities caused by injuries can be prevented by being careful in everyday life.
Otherwise, it is important to consult a specialist in good time if symptoms occur.
The quicker the diagnosis is made, the easier it is to treat the opacity.

A corneal opacity often develops gradually.
If you experience visual disturbances, eye pain or a persistent foreign body sensation, it is always advisable to have the symptoms investigated.

Frequently asked questions & answers about corneal opacity

Can corneal opacity be cured?

Corneal opacity can be treated well.
Depending on the cause of the corneal clouding, various treatment options are available: drug treatment, eye surgery (phototherapeutic keratectomy) and finally a corneal transplant.

How does corneal opacity manifest itself?

Corneal opacity can be visible externally.
It is characterized by a white film over the eye.
However, this is only the case at an advanced stage.
Initially, those affected experience visual disturbances, eye pain or a foreign body sensation.
If left untreated, corneal opacity can lead to blindness.

Can a corneal injury heal on its own?

If the corneal injuries are small and not deep, regeneration is possible.
However, scarring can also occur, which in turn promotes corneal clouding.
It is always advisable to consult a doctor in the event of an eye injury.