Mohan is a physician with over 20 years of experience in family medicine. He is a fellow of the Royal College of GPs, London.
Protect Your Eyes
It is not only our skin that is affected by the UV radiation from sun exposure. Our eyes are affected, too. The white part of the eye, called the sclera, is covered by a protective layer called the conjunctiva. This layer is prone to get irritated by the sun, as well as by wind, dust and smoke.
It can also become infected, leading to a red, inflamed eye that is sticky and painful. This is called conjunctivitis. Sometimes a blood vessel can burst in the conjunctiva, causing a hemorrhage.
Protecting the eye is essential when we are outdoors. The bright light can be quite a strain on our eyes—in particular, the conjunctival surface.
There are two conditions that are frequently confused with one another. Both are growths that can occur on the conjunctiva. Although both are benign conditions, they can be cosmetically disfiguring and also cause minor, annoying symptoms.
Common Symptoms Caused by Pterygium and Pinguecula
- Watering eyes
- Gritty feeling
- Constant feeling of having something in your eye
- Blurred vision (more in pterygium)
- Asymmetry and astigmatism
- Contact lens disruption
Pterygium and Pinguecula: Commonalities
Both pterygium and pinguecula are known to be caused by damage to the conjunctiva (a thin transparent membrane that covers the white of our eye, or sclera). There is a tendency to mistake one for the other. Although they are two distinct conditions, they do share certain common factors. Both can be caused by conjunctival degeneration due to sun exposure. Both appear as growths, usually on the nasal side of the eye (the half closer to the nose). Pinguecula can occur on both sides. Pterygium can also originate from a preexisting Pinguecula. Both show similar histopathological changes, such as elastotic degeneration.
They can both be brought upon by lack of lubrication to the eye, such as dry eyes due to low tear secretions as we get older.
They are both benign conditions that usually need no treatment and may eventually disappear.
While they share common traits, there are some fundamental differences between them.
- Protective eyewear
- Artificial tears: eye drops
- Antibiotic drops (only when infected)
- Irradiation with strontium particles
- Surgical excision and autograft
Pterygium (Tur-IJ-ee-um) is a fleshy growth seen on the nasal side of the conjunctiva (between the inner corner of the eye and the cornea). It looks like a tiny comet, with its head towards the iris and its tail towards the inner corner. It is denser towards its head and gets flimsier and even transparent towards the tail, looking like a little smear.
It is made up of fibrous and vascular tissue and tends to carry little blood vessels in its wake. Although it normally stays on the white of the eye, it can start to cross over the cornea and, in some cases, may obscure the iris and block the vision. Thankfully such aggressive growth is rare. It is slow growing and often looks like a triangular wedge with a superior and an inferior edge.
Pterygium always grows between the two eyelids in the exposed part of the eyes.
There may be some genetic predisposition to getting this problem, but largely it is due to frequent exposure to sun, sand and wind, causing damage to the conjunctiva. It is common in the Tropics due to the extent of round-the-clock sunshine. As it is commonly seen in some surfer's, it has been called 'Surfer's eye', but it is in no way exclusive to that sport. Any outdoor activity that involves constant assault on the eye surface can cause this.
The symptoms of pterygium are redness, itching, tearing, grittiness and occasionally blurred vision.
As it is a benign growth, it doesn't need removal unless it is aggressive and beginning to invade the cornea. It can be eased by protective eyewear and using gentle artificial tears regularly to improve lubrication. Irradiation and Surgical options are also available for larger more cosmetically disfiguring growths. However, there is always a chance of recurrence so long term eye protection and care are important.
Pinguecula (Pin-GWEK-yoo-lah) is seen as a yellow white nub on the inner aspect of the eye, close to the border between the cornea and the conjunctiva (limbus). This is also prevalent in the tropical regions and is caused by exposure to UV radiation. This is caused by degradation of the collagen fibers that constitute the conjunctiva and this leads to excessive accumulation.
Sunlight, often refracts through the cornea and focuses on a spot on the inner aspect of the eye sideways. This persistent exposure causes the growth. It is common above the age of 40 but can also be seen between 20-40.
The symptoms of pinguecula are similar. Tearing, redness, grittiness and irritation. Pinguecula will never grow into the cornea so does not cause visual disturbances. Although the constant irritation may lead to blurring due to excessive tears.
It is better to leave this well alone and sue lubricating eye drops that will help it to revert to normal. It does not need surgery as it is benign and not aggressive. Surgical options are available should the growth become too large and intrusive to the eye.
Differences Between the Two Conditions
Pale grey color
Flat, wedge shaped, like a comet
Raised nodule, like a meteor
Can grow into cornea
Doesnt grow into cornea
associated with tear film dysfunction
Mostly in the nasal part of the conjunctiva
Can occur on both sides, although common in nasal
This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.
© 2012 Mohan Kumar
Ruby Jean Richert from Southern Illinois on April 24, 2012:
A great detailed description between the two eye conditions. Very interesting, sunglasses a must..Thank you...
toknowinfo on April 24, 2012:
Now eye understand. Very interesting hub and eye learned a lot. Rated up and interesting.