Pterygium: How Sun Exposure Causes Eye Growth and What Surgery Can Do

If you’ve ever looked in the mirror and seen a pink, fleshy wedge growing from the corner of your eye toward your pupil, you’re not alone. This isn’t a rash, an infection, or a sign of aging-it’s pterygium, commonly called surfer’s eye. And if you live where the sun is strong-like Australia, Florida, or anywhere near the equator-it’s more common than you think.

Up to 23% of Australian adults over 40 have it. That’s more than 1 in 5 people. And it’s not just surfers. Farmers, construction workers, lifeguards, and even people who spend their lunch breaks outside without sunglasses are at risk. The sun doesn’t just give you a tan-it can literally grow tissue on your eye.

What Exactly Is Pterygium?

Pterygium starts as a small, raised bump on the white part of your eye, usually on the side closest to your nose. It’s made of conjunctival tissue-the same clear film that covers the inside of your eyelids and the white of your eye. But unlike normal tissue, this growth starts creeping onto your cornea, the clear front surface that lets light into your eye.

It looks like a wing-hence the name, from the Greek word pterygion. In early stages, it’s barely noticeable: a slight pinkness, maybe a few visible blood vessels. But over time, it can thicken, turn opaque, and stretch across the cornea. When it gets close to your pupil, it doesn’t just look weird-it starts messing with your vision. You might notice blurriness, glare, or a feeling like sand is always in your eye.

Doctors diagnose it with a simple slit-lamp exam. No blood tests. No scans. Just a bright light and a magnifying lens. That’s it. If the growth is touching the cornea, it’s pterygium. If it’s stuck on the white part only, it’s a pinguecula-a related but harmless bump that doesn’t threaten vision.

Why the Sun Is the Main Culprit

The science is clear: ultraviolet (UV) radiation is the #1 cause. Not just any UV-long-term, cumulative exposure. Studies show people who live within 30 degrees of the equator have more than double the risk. In Australia, where UV levels regularly hit 12 or higher, the numbers are staggering.

Dr. Robert A. Laing from the University of Melbourne found that people exposed to more than 15,000 joules per square meter of UV over their lifetime had a 78% higher chance of developing pterygium. That’s about 40 minutes of midday sun exposure, five days a week, for 10 years. No sunscreen on your eyes. No hat. Just the open sky.

It’s not just the intensity-it’s the reflection. Water, sand, snow, even concrete can bounce UV rays up into your eyes. Surfers get hit from above and below. Construction workers get hit all day. Kids playing outside without sunglasses? That’s building up damage silently.

And yes, genetics play a role. Some people are more prone. But even if you have the genes, you won’t get it unless you’re out in the sun without protection. Environmental exposure is the trigger.

When Does It Need Treatment?

Many people live with small pterygia for years without any problems. If it’s not growing, not bothering your vision, and not causing irritation, your doctor might just tell you to monitor it.

But here’s when you need to act:

• Your vision is blurry, especially when looking at distant objects
• You can’t wear contact lenses anymore because the growth makes them uncomfortable
• Your eye feels constantly gritty, red, or dry
• The growth is visibly expanding toward your pupil

That last one is critical. Once the pterygium crosses the 2-millimeter mark onto the cornea, it can start changing the shape of your eye. That leads to astigmatism-uneven focusing that makes everything look distorted. And once astigmatism sets in, glasses alone won’t fix it. You’ll need to stop the growth first.

Surgical Options: What Actually Works

If your pterygium is causing real issues, surgery is the only way to remove it. But here’s the catch: if you just cut it out, it has a 30-40% chance of coming back. That’s why modern techniques aren’t about removal-they’re about preventing recurrence.

Here are the three main surgical approaches used today:

1. Conjunctival autograft - The surgeon removes the pterygium and replaces it with a tiny piece of healthy conjunctiva taken from under your eyelid. This is the gold standard. Studies show recurrence rates drop to just 8.7% with this method.
2. Mitomycin C application - During surgery, the surgeon applies a mild chemotherapy drug (mitomycin C) to the area where the pterygium was. It stops abnormal cells from regrowing. Used alone, it cuts recurrence to 5-10%. Often, it’s combined with the autograft for even better results.
3. Amniotic membrane transplantation - This newer method uses tissue from a donated placenta. It’s gentle, promotes healing, and reduces inflammation. As of June 2023, European guidelines now recommend it as first-line treatment for recurrent pterygium, with 92% success in stopping regrowth.

The surgery takes about 30-40 minutes, is done under local anesthesia, and you go home the same day. Most people feel better within a week, but full healing takes 4-6 weeks. You’ll need steroid eye drops for up to two months to keep inflammation down.

Patients report big wins: 87% say their eye irritation disappeared. 65% noticed clearer vision right after healing. But 42% say discomfort lasted 2-3 weeks, and 37% were unhappy with the redness during recovery. It’s not glamorous-but it works.

What Happens If You Don’t Do Anything?

Some people think, “It’s not cancer. I’ll just wait.” But pterygium doesn’t stay still. Under constant UV exposure, it grows 0.5 to 2 millimeters per year. That might sound slow, but over a decade? That’s enough to cover your pupil.

And it’s not just vision. The constant rubbing of the growth against your eyelid causes chronic irritation. That leads to dry eye syndrome, which can damage your cornea long-term. In rare cases, it can even lead to permanent scarring on the cornea-something surgery can’t fully reverse.

Plus, once it’s big enough to interfere with vision, insurance may not cover the surgery unless you can prove it’s affecting your daily life. So waiting can cost you more-in money, comfort, and sight.

Prevention: The Real Game-Changer

Here’s the truth: surgery fixes the problem. But only one thing stops it from coming back: protecting your eyes from UV light-every single day.

Wear sunglasses labeled UV400 or that block 99-100% of UVA and UVB rays. ANSI Z80.3-2020 is the standard to look for. Wrap-around styles are best-they stop UV from sneaking in from the sides.

Wear a wide-brimmed hat. Even a baseball cap helps, but a 3-inch brim cuts UV exposure to your eyes by 50%.

Don’t wait until you feel discomfort. If the UV index is 3 or higher-which it is on over 200 days a year in Australia-you need protection. That includes cloudy days. UV penetrates clouds.

And if you’ve already got a small pterygium? Sun protection won’t shrink it-but it can stop it from growing. One Reddit user, an outdoor photographer, said his annual eye exams showed no growth for three years after he started wearing UV-blocking sunglasses daily.

What’s Next for Pterygium Treatment?

The field is moving fast. In March 2023, the FDA approved a new preservative-free eye drop called OcuGel Plus, designed specifically for post-surgery healing. It gave 32% more relief than regular artificial tears.

Right now, Phase II trials are testing a topical eye drop called rapamycin. Early results show it reduces recurrence by 67% compared to placebo. If it gets approved, it could mean people with early pterygium avoid surgery altogether.

By 2027, 78% of eye surgeons expect to use laser-assisted removal. It’s more precise, less invasive, and reduces healing time. The future isn’t just about cutting-it’s about smarter, gentler ways to stop the growth before it starts.

Final Thought: Your Eyes Are Worth Protecting

Pterygium isn’t a crisis. But it’s a warning. It’s your body saying: you’ve had too much sun. Too many days without protection. Too many years ignoring the signs.

If you’re over 40 and live in a sunny place, get your eyes checked. Even if you feel fine. A simple 10-minute exam can catch it early-and stop it before it changes your vision.

And if you’re young? Start now. Put on the sunglasses. Wear the hat. Don’t wait until you’re squinting at the road, or your contacts won’t stay in, or your eye looks like it’s growing a wing.

Your eyes don’t regenerate. Once the cornea is scarred, you can’t undo it. But you can stop it from happening.