An Interview With Dr. Kerry Assil Discussing Pterygium
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Dr. Kerry Assil, a world renowned ophthalmologist located in Beverly Hills and Santa Monica, California, is well known for his research and technology. Dr. Assil has trained over 14,000 surgeons on reconstructive, cataract and refractive procedures over the years, and has authored more than one hundred textbooks, textbook chapters and articles on refractive and cataract surgery. You may already be familiar with him, as he is a recurring guest on the popular informational TV program, “The Doctors.” He is also visible in many other media outlets including “Good Morning America," "The Today Show," Wall Street Journal, US News & World Report, Los Angeles Times, USA Today, Time, People Magazine, and InTouch Magazine.
He is the physician of choice for the Los Angeles Kings. His practice is proud to treat anyone who needs care but among his celebrity patients are Brad Pitt, Courtney Cox & LeBron James.
I recently spoke to Dr. Assil about the dangers of ultraviolet damage to the eyes including the development of pterygium.
Tell me about pterygium.
A pterygium (ter-IDG-ee-um) is a benign, wedge-shaped growth that develops on the surface of the white part of the eye. It sometimes appears very red and may be elevated. The word is derived from the greeks and latins and literally means "wing glides or wing span." It was from the observation that it looked like the tip of the wing of a bird and appeared that it was growing over the eye. It usually starts growing near the inside corner of the eye toward the nose and can extend onto the cornea. It can grow on the temporal side of the eye as well, but 90% of the time it is on the nasal side. Pterygium tend to grow on the nasal side of the eye because it gets a double dose of UV radiation, one being from the direct sunlight and two, from the UV rays which bounce off the side of the nose and back into the eye.
Pterygium is sometimes referred to as Surfer’s eye because the more sun exposure you have, the more likely you are to have a pterygium. So looking more at the sun as the origin, the closer you live to the equator, the less you wear sunglasses, the more you are out in the sun and in particular, with wind, doing activities, the more at risk you are for developing a pterygium. The ultraviolet energy from the sun transforms the cells of the surface of the eye and causes chronic irritation. These changes begin to create a form of scar tissue.
Why does severe dryness increase the risk of pterygium?
People exposed to a lot of wind where their eyes become very dry seem to have pterygium that can become worse or grow faster. The leading edge of the pterygium often grows up onto the cornea, the clear dome-like structure on the front part of the eye. Once it does that, the eyelid can no longer properly lubricate the eye with each blink. A way to understand this is to think about the space under a windshield wiper that can’t get to the windshield - you get a dry spot. Every time you blink, the eyelids can’t coat that area where the the pterygium grows up onto the cornea. As that area dries out, the cells break down and the scar tissue grows forward.
What are some common complaints of your patients with pterygium?
My patients will often complain of dryness, redness, foreign body sensation, irritation, scratchiness and blurriness.
Can it continue to grow over the cornea?
When this type of growth is localized to just the nasal or temporal part of the white part of the eye, it is called a pinguecula. The word "pinguecula" also has latin roots and means fatty tissue. It appears like a thickened, yellowish fatty nodule. As it grows and turns into the triangular-winged shape and grows up onto the cornea, it is called a pterygium. Once it grows up onto the cornea, it can cause blurred vision.
What impact can pterygium have on vision?
A pterygium can create large amounts of astigmatism and some corneal distortion. When it is removed, much of this goes away. It was previously thought that a pterygium causes a constriction of the cornea, causing a change in corneal curvature and unwanted astigmatism. This has more to do with the fact that the tissue is elevated and adjacent to the visual axis. This elevation changes the curvature of the tear film in that direction. It is not really a tension on the cornea, but rather a change in the tear film that can cause blurry vision.
How do you treat pterygium?
First, we recommend lifestyle changes to avoid growth or inflammation of a pterygium such as limiting sun exposure, wearing adequate sunglasses with high quality UV protection and maybe wearing wide brimmed hats. Also, it is important to get a good night's rest! Lack of sleep can dry the surface of the eye and increase risk for pterygium growth and inflammation. Tear film production is dependent on rest in order to reboot itself. Then we start most patients on lubricating drops or artificial tears given several times per day, especially while outside or in the wind. If we are concerned more about the dryness part of the disease process, we will perform punctal occlusion, a painless procedure where we insert collagen or silicone plugs or inserts into the tear drainage system to allow the natural tears to stay in the eye longer to lubricate the eye. This prevents or slows the drainage of your own tears so they coat the surface of the eye longer. Next, we move on to prescribing mild steroid eye drops to quell the underlying inflammation. Of course the steroids are given as a short course because steroids can have side effects in some patients causing a rise in the intraocular pressure (pressure inside of the eye) and can also cause cataract formation, which is a loss of the transparency in the natural lens of the eye. As a result, we monitor any patient using steroid eye drops very closely.
Do you recommend surgery to remove pterygiym?
The decision to move toward surgery is really up to the patient. In my practice, I listen to the patient. Some patients want it removed because they are having symptoms such as scratchiness or blurred vision. Others are concerned about their cosmetic appearance and still others, “just want that red thing gone!” As a result, I listen to what's important to the patient and what is medically sound and then make the decision.
Will a pterygium regrow after surgery?
In the past pterygiums had a very high rate of regrowth. However, with today’s advanced surgical techniques and excellent medications and in the hands of a meticulous, skilled surgeon, the re-growth rate is very low at less than 2%. We also use special amniotic graft tissue that is very helpful in healing and preventing recurrence. Without the use of the amniotic membrane grafting, the regrowth rate is as high as 50%.