Pterygium and Pinguecula: Causes, Symptoms and Surgery Options

If you have noticed a small yellowish bump on the white of your eye, or a pink, fleshy, wedge-shaped growth creeping from the corner of the eye towards the coloured iris, you are likely looking at a pinguecula or a pterygium. Both are common, non-cancerous changes in the conjunctiva, the thin transparent membrane that covers the white of the eye. They are strongly linked to years of sunlight, wind and dust, which is why pterygium is sometimes called surfer's eye.

Most of these growths are harmless and cause only occasional redness or irritation. A pterygium that grows far onto the cornea, however, can distort vision, and surgery may be needed. This guide explains the difference between the two conditions, what causes them, how to relieve symptoms, when surgery is advisable and how modern techniques such as conjunctival autografting reduce the chance of recurrence.

Pinguecula and pterygium: what is the difference?

Both conditions arise from degenerative changes in the conjunctiva, in which collagen and elastic tissue are damaged, largely by UV light. They usually appear on the side of the eye nearest the nose, probably because sunlight reflects off the side of the nose and concentrates on that area.

The name pterygium comes from the Greek word for wing, describing its shape. A pinguecula (from the Latin for fat, because of its yellow colour) may sometimes precede a pterygium, though many people have a pinguecula that never changes.

Causes and risk factors

The strongest risk factor is cumulative exposure to UV light. Studies consistently find higher rates of pterygium in regions closer to the equator, among people who spend long hours outdoors and in sunny, dusty or windy environments. Other contributing factors include:

• Outdoor occupations and hobbies: farming, fishing, construction, surfing, sailing, skiing and other water and snow sports, where light is reflected from water, sand and snow.
• Dust, sand and wind, which irritate the eye surface.
• Dry eye and low humidity, which make the conjunctiva more vulnerable; see our dry eye guide.
• Age: both conditions are more common from middle age, reflecting years of exposure.
• Genetic factors may play a role, as pterygium sometimes runs in families.

Our article on snow blindness and UV damage explains how UV light affects other parts of the eye too.

Symptoms

Many people have no symptoms at all and notice the growth only in the mirror or when someone comments on it. When symptoms do occur, they include:

• Redness, especially after sun, wind, dust, smoke or air conditioning.
• A gritty, burning or foreign-body sensation, as if there is sand in the eye.
• Dryness and watering.
• Swelling and inflammation of the growth, sometimes called pingueculitis when a pinguecula becomes inflamed.
• Difficulty wearing contact lenses.
• Blurred or distorted vision if a pterygium pulls on the cornea and causes astigmatism or approaches the pupil.
• Cosmetic concern about a visible pink or yellow lesion.

Diagnosis

An optometrist or ophthalmologist can usually diagnose pinguecula and pterygium with a slit-lamp examination. They will assess how far a pterygium has grown onto the cornea, whether it is inflamed and whether it is affecting vision. Corneal topography may be used to measure the astigmatism a pterygium induces, and photographs help track growth over time. Unusual lesions may need a biopsy.

Lubrication and everyday care

For most people, simple measures are all that is needed:

• Lubricating eye drops (artificial tears) soothe dryness and grittiness. Preservative-free drops are better if you use them frequently. Gels or ointments at night can help when symptoms are worse. Our guide on eye drops and the article on choosing artificial tears explain the options.
• Cool compresses can calm an irritated, red eye.
• Short courses of anti-inflammatory drops may be prescribed by a doctor when a pterygium or pinguecula becomes inflamed. Steroid drops should only be used under medical supervision because they can raise eye pressure and cause other side effects.
• Avoid redness-relieving drops (vasoconstrictors) for regular use; they can cause rebound redness.

Protection from UV and dust

Protecting your eyes is the most important long-term step and may slow growth or reduce the chance of recurrence after surgery:

• Wear sunglasses that block 100 percent of UVA and UVB (marked UV400 or with a recognised standard) whenever you are outdoors in daylight, including on cloudy days.
• Choose wraparound styles or close-fitting frames that block light from the sides.
• Add a wide-brimmed hat or cap to reduce UV by a further margin.
• Use protective goggles in dusty or windy work and during water and snow sports.

See our guide to sunglasses: UV, polarisation and categories for help choosing a pair.

When is surgery needed?

A pinguecula rarely needs surgery, although it may occasionally be removed if it is chronically inflamed, interferes with contact lenses or is a major cosmetic concern. Surgery for pterygium is typically considered when:

• It is growing towards the centre of the cornea and threatens the visual axis.
• It causes significant astigmatism or blurred vision.
• It causes persistent irritation or inflammation despite drops.
• It restricts eye movement (in advanced cases) or causes double vision.
• It interferes with contact lens wear or planned surgery such as cataract or laser refractive surgery.
• It is cosmetically troubling, after careful discussion of the risks.

Removing a pterygium before it reaches the pupil area usually gives a better result, because once it has grown far onto the cornea it can leave a scar even after removal.

Pterygium surgery with conjunctival autograft

Pterygium surgery is usually a day-case procedure under local anaesthetic and takes around 30 to 60 minutes. The surgeon carefully removes the pterygium from the cornea and the conjunctiva and smooths the corneal surface.

Simply removing the pterygium and leaving the white of the eye bare (bare sclera technique) is associated with high recurrence rates, often reported in a large proportion of cases. To reduce this, the standard approach now is a conjunctival autograft: a thin piece of healthy conjunctiva is taken from under the upper eyelid of the same eye and placed over the area where the pterygium was removed. The graft is secured with tiny stitches or, increasingly, with a tissue glue (fibrin glue), which shortens surgery and is often more comfortable.

A Cochrane review found that conjunctival autografting is associated with a lower risk of recurrence than amniotic membrane grafting. In some cases, especially recurrent pterygium, surgeons may also use an anti-scarring medicine such as mitomycin C, applied carefully during surgery.

Recovery

After surgery, the eye is usually padded overnight. You can expect redness, a gritty or scratchy feeling and watering for one to two weeks, and the eye may remain somewhat pink for several weeks. Steroid and antibiotic drops are prescribed for several weeks to reduce inflammation and recurrence risk. Most people return to desk work within a few days; dusty or outdoor work may need longer. Avoid rubbing the eye, swimming and dusty environments until your surgeon says it is safe.

Recurrence and how to reduce it

Recurrence means the pterygium grows back, usually within the first year after surgery. It is more likely in younger patients, those with large or very inflamed pterygia, and people who continue high UV exposure. A recurrent pterygium can grow more aggressively than the original, so careful technique and follow-up matter. To lower the risk:

• Use your prescribed drops exactly as directed and attend follow-up appointments.
• Wear UV-blocking sunglasses and a hat outdoors for life.
• Keep the eye surface lubricated and treat dry eye.
• Report any regrowth early, when it is easier to treat.

When to see a doctor

See an optometrist or ophthalmologist if you notice a new growth on your eye, if a known pinguecula or pterygium is getting larger, becomes repeatedly red and sore, or if your vision becomes blurred or distorted. People who work outdoors should have regular eye examinations.