A pterygium is a benign (not cancerous) overgrowth of tissue on the surface of the eye. It may in part be due to damage to the surface tissues of the eye from long term exposure to sunlight. A pterygium starts growing near the limbus (the border area between the white of the eye (sclera) and the clear window at the front of the eye (cornea). They commonly arise on the side of the eye closest to the nose. It usually takes many years for a pterygium to grow very slowly across onto the cornea. A pterygium may even appear to stop growing and in most cases will pose no threat to the vision.
In amost all patients there is no urgency to remove a pterygium. If your eye doctor feels that the pterygium is growing close to your line of sight (visual axis), then removal of the lesion may be advised. If the pterygium is not a threat to your vision, then you may still wish to have it removed for cosmetic reasons or if it is giving you significant discomfort.
If you decide not to have the pterygium removed, then you can use simple preservative-free lubricating drops (eg. Cellufresh, Poly Tears) as often as necessary for the discomfort – these are available on prescription or over the counter from your chemist. It is advisable to wear a wide-brimmed hat and/or ultra-violet protective sunglasses when outside in bright sunlight to try and prevent further growth.
Removal or excision of a pterygium is usually performed under local anaesthesia as a day surgery procedure. Local anaesthetic drops are placed on the eye to numb the surface tissues. A small injection of anaesthetic is then given in to the pterygium itself, but this will hardly be felt. The lesion is then shaved off the surface of the eye with a very sharp fine blade.
At this stage, the wound could be left to heal, but there would be a very high risk of regrowth or recurrence of the pterygium. To reduce this risk, a rectangular graft of tissue, approximately 1cm by 0.5cm, is taken from the conjunctiva of the same eye (conjunctival autograft) and stitched or sutured into the wound that was left when the pterygium was excised. The entire procedure is painless and takes about thirty minutes. A firm pad is then taped over the eye and will remain in place until your eye doctor sees you the next day.
Following the Operation
The local anaesthetic will wear off after a couple of hours and you may experience considerable discomfort or pain over the next 12 hours. You will be given a script for strong pain relief tablets, but very rarely you may need to visit your local doctor, locum service or hospital emergency department for additional pain relief.
The pad will be removed the following day and your eye doctor will examine your eye. You will be commenced on an antibiotic drop (eg. Chlorsig) three times per day, and a steroidal anti-inflammatory drop (eg. Prednefrine Forte) six times per day for the next seven days. During this week, your eye will be quite irritable, but severe pain or a sticky discharge should be reported immediately.
You will be seen again at the end of this week and your drop regimen will be altered according to the healing response of the wound. Your eye doctor will keep you under close review until you are off all drops, but you may need to be on a mild steroid drop (eg. Predsol) for up to two months following the operation. Your eye doctor will want to see you again four to six months following the operation to make sure there is no sign of recurrence of the pterygium.
Risks of the Operation
Any operation on the eye exposes the eye to small but significant risks. There is always a risk of infection when there is a wound on the surface of the eye. A severe infection could threaten the sight in the eye, but the chance of loss of vision following pterygium surgery is extremely low, particularly if you take your antibiotic drops as prescribed.
The other significant risk is that of recurrence of the pterygium, but the chance of this is less than 10%, particularly if you take your anti-inflammatory drops as prescribed. The continued wearing of sunglasses and a hat following the operation may reduce this risk further.
It is important to remember that there may be some continued redness at the site of the operation, and occasional discomfort, but these should settle with time. You may need to continue using a lubricating drop from time to time following the operation.
If you continue to have difficulty following the operation or if you suspect a recurrence of the pterygium, it is important that you return to see your eye doctor.