The condition in which a white-yellow mucous membrane grows on the cornea of the eye from the tear duct to the center of the eye is called Pterygium. The growth has the shape of a triangle and resembles a wing with visible blood vessels in it. The condition is therefore noticeable because the cornea is normally white, while the condition shows all red blood vessels. Depending on where one lives, it occurs very often or rarely. The closer you live to the equator, the number of cases increases, but it also occurs frequently among surfers. What causes Pterygium and what else can be done about it?

Pterygium: red corneal growth

• Structure of the eye
• Degrees of the growth
• Probable causes Pterygium
• The complaints
• What can one do about it in everyday life?
• Treatment of the condition

Structure of the eye

The eye is an important source of information for us as a person because the world is viewed through the eye and further processed by the brain. To absorb that information, the eye is constructed as follows:

• the surface of the eye is covered by the cornea and its function is to retain eye fluid, protect the eye and direct light to the lens;
• the ophthalmic fluid chamber for the lens;
• In that chamber there is the iris in front of the lens, which gives the eye a special eye color, as it were. This is also called the iris;
• The lens then follows, which further bundles the light so that it is projected onto the retina. The image is translated via the retina into color and shape, with which we can recognize the outside world.

If a Pterygium grows, it slowly moves from the corners of the eye to the center of the eye. This often remains on the white part of the eye, but can also grow on the cornea in front of the iris or lens. The latter means that the incoming light can be disturbed by the condition, resulting in deteriorating vision, because the light is incorrectly focused through the lens.

Degrees of the growth

The condition can be classified into different degrees. On the one hand, there is the size of the growth:

• it grows above the normal white cornea and therefore does not directly affect vision. It often manifests itself in a white-yellow spot with red blood veins;
• it grows above the iris. The iris controls how much light enters the eye. When it is dark at night, the iris can be opened properly to capture extra light. Due to the growth, light penetration decreases and a blockage may temporarily be seen;
• it grows above the aperture of the lens. This is the inner black part of the eye where the lens is located. This can lead to complete blocking of light, which can cause partial blindness.

In addition to size gradations, there are also gradations for the progress of the tissue. The following three gradations can be distinguished:

• atrophic: the growth is transparent, making the supplying blood vessels clearly visible;
• intermediate: the tissue begins to acquire a more dense structure, so that the blood vessels are partly no longer visible;
• fleshy: this is the form in which the condition has reached the adult stage. The fused tissue has taken a firm shape and the blood vessels are no longer visible. The growth takes on a more yellowish color so that it can be clearly distinguished from the underlying cornea.

Probable causes Pterygium

Because the condition becomes more common the closer one lives to the equator, there is probably a relationship between solar radiation and the condition. In Europe, the condition mainly occurs in the areas around the Mediterranean Sea. The condition also occurs in the Netherlands, because it can sometimes be quite hot here in the summer, and we also like to go on holiday to hot places. The following causes appear to further underlie the condition:

• UV radiation from the sun, but possibly also UV radiation from a tanning salon;
• dry climate and dustiness, but smog can also play a role;
• exposed to wind outside, but also in the house through the fan.

The complaints

Usually there are no complaints if the condition occurs. This is because it sometimes goes unnoticed, because deformity does not grow beyond the white part of the eye. However, the condition can cause the following symptoms:

• corneal irritation because you have the constant feeling that there is something in the eye, or that it feels irritated or dry;
• If the condition grows beyond the iris, vision may be reduced due to reduced light. If the growth reaches the center of the iris, this means that the yellow spot in the eye does not receive enough information and focuses on the condition itself (the eye focuses on the information that the yellow spot receives).

What can one do about it in everyday life?

If it has been established that you have pterygium disease on the cornea, this does not mean that you will immediately have problems with your vision. With this deformity you can generally no longer wear contact lenses, as they become uncomfortable. If the weather is windy, hot or dusty and you go outside, wear UV-resistant sunglasses. The glasses repels the suspected causative agent and also prevents wind from coming into the eye. This also prevents irritating allergic dust particles from blowing into the eye. If you have a fan at home, do not aim it straight at your face, but let the fan blow from the side. Thus, you can reduce the prominence and irritation of the eye.

Treatment of the condition

The eye may be very irritated by the condition. Then you can use eye drops to reduce the influence of dry eyes. If the growth is in an advanced stage, it may be necessary to remove it. This can be done surgically. The following treatment can be performed under local anesthesia. The cornea affected by the condition is completely removed up to 5 mm away from the tear duct. The resulting wound is filled with a graft taken from the same eye (this heals quickly on its own). The replacement tissue is secured with eye glue or sutures (this produces a gritty feeling to the eye for the first few days). During the first few days after treatment, it is essential that you do not touch your eyes. You must wear a blinder. Once the wound has healed, there is a chance that the Pterygium will return over time.

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