What is a pterygium?
A pterygium (pronounced ter-ij-ee-um) is a wing shaped growth of tissue across the cornea, which is the clear window at the front of the eye. It is sometimes known as a “pearl“ because it looks white.
It nearly always forms on the part of the cornea, which is visible when the eye is open. It is most often occurs in people who have lived in a hot dusty country or have worked outdoors for many years. It may be due to drying of the eye. It is not a cancer, but it can get slowly larger with time.
How does a pterygium affect the eye?
In the early stages the eye may feel uncomfortable and look slightly red but vision is
unaffected. However, if the pterygium grows a lot, it may blur the vision, although this is
unusual.
What treatment is there for pterygium?
If the pterygium is small, no treatment is required. If the eye is uncomfortable, lubricating
drops and / or ointment may help. Hypromellose or Liquifilm drops and Simple or Lacrilube
ointment are suitable. These can be obtained from your GP or bought at your local
pharmacy and can be used long term if needed.
If the pterygium advances until it is at the edge of the pupil or if it is enlarging and very
uncomfortable, it is best to have it surgically removed.
What is the surgery for pterygium?
This is usually performed under local anaesthesia as a day case in the operating theatre at
the Eye Unit. You can eat and drink normally before the operation .The eye is numbed with
drops and an injection and the eyelids are held open for you. The pterygium is scraped off
the cornea and the sclera (white of the eye). A piece of conjunctiva from under your upper
lid is removed and grafted onto the bare sclera, but the cornea is left to heal by itself. Only
absorbable stitches are used. These do not have to be removed but will dissolve and fall
out over the next few weeks. The eye will be covered with a pad.
What happens after the operation?
You will be offered a drink before you leave the hospital. You will be given drops to use in
the eye once the dressing is removed. These drops need to be continued for several
weeks and you should get a repeat prescription from your GP if you think you will run out.
Do not stop the drops until the clinic doctor tells you to.
The eye may feel quite sore for a few days. You can to take painkilling tablets regularly.
The hospital will give you a small supply – ask you GP for more if needed.
You may need several follow up visits to clinic. The first one will be arranged before you
leave hospital. You may need at least a week off work so please ask the hospital for a
certificate if you need one.
Surgical removal is advisable in cases where:
Redness due to numerous blood vessels in the pterygium makes the eye look bloodshot. (Topical medications can reduce this temporarily);
The leading edge of the pterygium pulls the cornea, distorting its shape causing astigmatism;
Normal vision is threatened by a large pterygium growing over the pupil;
Persistent irritation, tearing and discomfort are experienced;Pterygium interferes with the wearing of contact lenses;
Appearance of pterygium is unsightly.
What problems are there after surgery?
Pain - this should settle within a few days with painkillers, but please contact the
hospital if it is getting worse despite regular medication.Redness. The eye may look redder for a few days after surgery but will gradually
improve with time.Side effects from drops. Occasionally an allergy develops due to the drops or a
pressure problem in the eye. The clinic doctor will check for these problems.The eye may still not have a perfectly smooth surface after surgery and lubricating
drops may still be required.Scarring of the eye surface and eye muscles can occasionally cause restricted
movement of the eye and double vision. Further treatment would probably help.The pterygium could come back again. This is much less common with modern
surgery, but is occasionally very troublesome. Re-operation may be possible.
The exact cause of pterygium isn’t known. One explanation is that too much exposure to ultraviolet (UV) light can lead to these growths. It occurs more often in people who live in warm climates and spend a lot of time outdoors in sunny or windy environments. People whose eyes are exposed to certain elements on a regular basis have a higher risk of developing this condition. These elements include:
- pollen
- sand
- smoke
- wind eResearch by Navid Ajamin -- spring 2013
Other risk factors include having light skin and light eyes.
Diagnosing a pterygium is straightforward. Your eye doctor might be able to diagnose this condition based on a physical examination using a slit lamp. This lamp allows your doctor to see your eye with the help of magnification and bright lighting. If your doctor needs to do additional tests, they might include:
- a visual acuity test, which involves reading letters on an eye chart
- corneal topography, which is used to measure curvature changes in your cornea
- photo documentation, which involves taking pictures to track the growth rate of the pterygium
If possible, avoid exposure to environmental factors that can cause a pterygium. You can help prevent the development of a pterygium by wearing sunglasses or a hat to shield your eyes from sunlight, wind, and dust. Your sunglasses should also provide protection from the sun’s UV rays. If you already have a pterygium, limiting your exposure to the following can slow its growth:
- wind
- dust
- pollen
- smoke
- sunlight
It can also help prevent them from coming back if you’ve had any removed.
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Reference:
- Pterygium - patient information University Hospital Southampton - NHS Foundation Trust
- healthline.com/health/pterygium#treatments6
- rodgerdavies.com.au/pterygium
See Also:
Pterygium emedicine.medscape.com
Pterygium Patient Education Video (18+)
Pterygium nlm.nih.gov
وبلاگ تخصصی عینک شامل مجموعه مطالب پزشکی است که اطلاعات مفیدی در رابطه با عینک , چشم، لنز، سلامتی چشم و راه های پیشگیری از بیماریهای چشمی، کنترل و درمان آن را در اختیار شما کاربر محترم می گزارد.
