Pterygium
What is a pterygium?
A pterygium is a fleshy, vascular overgrowth of the jelly-like conjunctiva onto the surface of the cornea. It may have a wedge shape to it, so it was named after the Greek word for “wing.” It is correlated with sun exposure, and dry, dusty environments. Theories about the source of pterygia (plural) abound, and studies cite evidence for infectious agents, genetic mutations within tissue, and familial genetic markers, for example. Commonly, the pterygium extends from the conjunctiva, which is usually transparent except for some fine blood vessels, over the limbus on the side towards the nose.
Sometimes a person can have pterygia coming from both directions, filling in the space between the eyelids. Often, especially in older people, pterygia can be quiescent and flat, and not progressive over years of observation.
However, especially in younger people who work and play outdoors, pterygia can be irritable, with frequent bouts of redness due to proliferation of the blood vessels and elevation of the tissue out of the tear film. Besides not looking great, “pterygi-itis” makes the person’s eye light sensitive, tender, and scratchy.
Should I have it removed?
You might consider removal if the pterygium becomes repeatedly inflamed, shows growth, or produces changing astigmatism even without growth towards the pupil. A pterygium can induce astigmatism by steepening the curvature of the cornea in the horizontal direction—think how a finger on a guitar string tightens it up. It’s frustrating if your glasses are changing frequently due to fluctuating corneal curvatures and unstable astigmatism.
Will insurance cover its removal? Isn’t that cosmetic?
Repeated irritation and unstable glasses correction are clear-cut reasons to remove a pterygium. You don’t wait until the pterygium gets too close the central cornea, over the pupil. With documented growth and symptoms, surgery to remove pterygia is reasonable, and covered.
Are pterygia precancerous?
Generally, no.
What can I expect from the exam?
We perform a thorough evaluation, including measurement of astigmatism, including a topographic map of the cornea that is very valuable to follow over time. This corneal map shows the effect of the pterygium even on tissue not under or directly adjacent to it.
We evaluate the look of the tissue and grade it for severity. We look for other factors that might be addressed to make the eye more comfortable, slow and even reverse the progress of the pterygium, or if surgery seems likely, make the surface of the eye quieter so that healing goes more smoothly.
So you can improve pterygia without surgery?
It’s often worth a try if it’s not too large. Some things to address:
• Rosacea, the eye’s reaction to the microorganisms that surround it, can be diminished, with improvement in the environment of the pterygium. For example, warm compresses followed by a gentle ocular disinfectant quiet the eye. (See suggestions under Blepharitis)
• A short course of topical and oral medications, like antibiotics and the judicious use of steroids, soothes the more severe, uncomfortable episodes of inflammation.
• Omega fatty acids taken orally have good effects on the fluidity and anti-inflammatory characteristics of the oil glands around the eyes, the Meibomian glands. (See suggestions under Blepharitis)
• Ultraviolet exposure is undoubtedly linked to increased incidence and exacerbation of pterygia. Avoid it, by using sunglasses and a hat with a brim.
• There is a role for allergy medications in quieting the conjunctiva, if there seems to be a seasonal component to flare ups. Consider the use of mast cell inhibitors. Don’t overdo the “get the red out” drops, which whiten the eye by constricting blood vessels. There might be rebound redness when you stop them, and the constant use of these drops with their preservatives may lead to a sicker surface.
• More aggressive therapy short of surgery might include injection of long acting steroid into the pterygium, or injection of an antifibrocytic drug (mitomycin C). However, these drugs must be used very cautiously due to their potential side effects, with close supervision afterward.
