What are the other Names for this Condition? (Also known as/Synonyms)
- Conjunctival Pterygium
- Surfer’s Eyes
- Web Eye
What is Pterygium? (Definition/Background Information)
- Pterygium is a common disorder affecting the eyes. It is usually found in those with prolonged exposure to the sun’s ultraviolet rays, which may be due to outdoor work. In this condition, the white of the eye develops a thick membrane, which slowly grows over the cornea of the eye, causing vision problems
- Pterygium means "wings" in Greek language. The thick membrane over the white of the eye appears like a wing, and hence the name
- The condition usually affects the white of the eye, which is closer to the nose, than the white that is nearer to the ears
- It can occur either in one eye or both the eyes. When the disorder occurs in both the eyes, it is called Bilateral Pterygium
- The membrane is benign (non-cancerous) and in most cases, the condition can be resolved by surgical removal
Who gets Pterygium? (Age and Sex Distribution)
- Individuals living closer to the equator are more prone to Pterygium
- It usually affects middle and older age group individuals. It is not generally observed in children
- Both males and females can get Pterygium. However, it is slightly more common in males, than in females
What are the Risk Factors for Pterygium? (Predisposing Factors)
The risk factor for Pterygium includes:
- An increased exposure to the sun’s ultraviolet rays increases the risk. Hence, this may account for higher frequency incidence of Pterygium in individuals, living closer to the equator (tropical region)
It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.
Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.
What are the Causes of Pterygium? (Etiology)
- The exact cause of Pterygium is unknown
- Some researchers believe that exposure to UV light may play a significant factor in the development of this disorder. Some also believe that Pterygium of the eye is similar to actinic keratosis of skin
- Sun exposure increases the risk, due to increased exposure of the eyes to UV light. This is especially observed in those individuals living close to the equator (tropics), and those performing prolonged outdoor activities without proper eye protection
- Other researchers believe that the cause of Pterygium could be due to variety of factors, such as abnormal inflammation in the eye, abnormal blood vessel growth, viral infection, lack of tears in the eyes, and deficiency of a chemical called choline, in the eyes
What are the Signs and Symptoms of Pterygium?
In many individuals, Pterygium does not cause any signs and symptoms. In those whom it does, the following may be observed:
- Vision problems, unable to have a clear vision
- Irritation of eyes with feeling of foreign body presence in the eyes, causing redness
- Thin membrane formation over the white and/or cornea of the eye. Sometimes, the membrane is thick and opaque. This may cause cosmetic issues
- Squint eyes
How is Pterygium Diagnosed?
A diagnosis of Pterygium would involve:
- A complete physical examination and a through clinical history
- Slit-lamp examination of the eye
- Visual acuity testing
- Corneal topography studying the surface of the cornea
- Motility examination of the eyes, for studying eyeball movement and evaluating muscle function of eye
- Visual field examination of eye
- Testing for intraocular pressure, through measurement of eye pressure
- Examination of the back of the eyes (fundus and retina) through a dilated funduscopic exam
- Surgical biopsy by removal of the Pterygium and examination of the tissue by a pathologist under a microscope
The pathologist will note that there is degenerated tissue (which appears as grayish blue material) below the squamous epithelium with hyperplasia of the squamous epithelium. The squamous epithelium may show features of dysplasia. There may be a reactive increase in goblet cells, as a reactive feature.
Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.
What are the possible Complications of Pterygium?
The following are some of the possible complications of Pterygium:
- Recurrence of Pterygium
- Damage to cornea, such as perforation and scarring
- Side effects to treatment
How is Pterygium Treated?
No treatment is needed for asymptomatic individuals. In those with Pterygium that need treatment, medical and surgical treatment options are available, based upon the individual's specific circumstances. These include:
- In many cases, non-surgical methods are used first. This includes lubrication of eyes using saline drops and ointments. Using eye drops containing steroids may also help by decreasing the eye inflammation
- Surgical treatment method includes removal of Pterygium (simple excision). The major complication of this simple excision, without providing any further treatment, is that the Pterygium recurrence rate is very high (up to 80%)
- Current preferred method of treatment is surgery, in combination with topical chemotherapy and/or radiation treatment. This combination treatment greatly reduces the recurrence rate
- The current choice of surgery is the use of a surgical method, called conjunctival flap/graft. The use of autograft has decreased the recurrence rates, even further. This is called PERFECT procedure, which stands for Pterygium Extended Removal Followed by Extended Conjunctival Transplant
- Periodic follow up after surgery is a must, in order to detect recurrences early (if they occur)
How can Pterygium be Prevented?
The exact cause of the disorder is unknown. However, the following measures may help prevent Pterygium:
- Protect eyes from sun exposure by wearing protective glasses. The use of protective (wide-brimmed) hats can also help decrease sun exposure
- Use lubrication for dry eyes frequently, which could be in the form of saline drops and artificial tears
What is the Prognosis of Pterygium? (Outcomes/Resolutions)
The prognosis with Pterygium is usually excellent, with prompt treatment, in symptomatic individuals.
Additional and Relevant Useful Information for Pterygium:
- Pterygium is not a kind of cancer, and it is not contagious
- Pterygium always starts off as a focal disorder (focal formation of membrane), and this focal condition is called Pinguecula. Pinguecula is also a very common condition