{"id":1848,"date":"2026-10-20T08:52:59","date_gmt":"2026-10-20T08:52:59","guid":{"rendered":"https:\/\/laseristanbulclinic.com\/eye-glossary\/pterygium\/"},"modified":"2026-10-20T12:57:12","modified_gmt":"2026-10-20T12:57:12","slug":"pterygium","status":"publish","type":"page","link":"https:\/\/laseristanbulclinic.com\/en\/eye-glossary\/pterygium\/","title":{"rendered":"Pterygium: What It Is, Causes, Symptoms and Treatment"},"content":{"rendered":"\n
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  4. Pterygium: What It Is, Causes, Symptoms and Treatment<\/span><\/li><\/ol><\/div>\t\t\t

    Pterygium: What It Is, Causes, Symptoms and Treatment<\/h1>\n\t\t\t\t\t\t

    Medically reviewed by {{surgeon}}<\/span><\/strong>, {{surgeon’s title and specialty}}<\/span>, on {{review date}}<\/span>. Last updated {{date}}<\/span>.<\/p>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t

    \"Illustration<\/figure><\/div>\n\t\t\t<\/div><\/div>\n<\/section>\n\n\n\n\n
    \n\t\t<\/svg>Definition<\/span>\n\t\t\t

    Pterygium<\/strong> (noun, pronounced ter-IJ-ee-um; plural pterygia)<\/em>: a pterygium is a fleshy, wing-shaped growth of tissue that starts on the conjunctiva (the clear membrane over the white of the eye) and spreads across the edge of the cornea, usually from the side nearest the nose. It is not cancer, and it is caused mainly by long-term exposure to sunlight (ultraviolet light), wind and dust. Many pterygia cause only mild irritation, but a growing one can distort vision and, if it threatens sight, is removed with surgery, which at Laser Istanbul Clinic is led by Do\u00e7. Dr. Muhammet Derda \u00d6zer, our cornea specialist.<\/p>\n\t\t<\/div><\/div><\/div><\/div><\/section>\n\n\n\n\n

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    Pterygium: key facts<\/h2><\/div>\n\t\t\t\t\t<\/div>\n\t\t\t
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    <\/svg>What it is<\/span><\/dt>
    A benign, wing-shaped growth of conjunctival tissue with blood vessels that grows onto the cornea<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>Name<\/span><\/dt>
    From the Greek pterygos<\/em>, “wing” (EyeWiki, AAO)<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>Where it starts<\/span><\/dt>
    At the limbus, the border between the white of the eye and the cornea; more often on the nasal side than the temporal side<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>Main cause<\/span><\/dt>
    Ultraviolet (UV) light exposure, with wind and dust as contributing factors<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>How common<\/span><\/dt>
    A 2013 meta-analysis of 20 population studies (900,545 people) found a pooled prevalence of 10.2% worldwide, higher closer to the equator and in older people<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>Usual symptoms<\/span><\/dt>
    None at first; later irritation, redness, a gritty feeling, watering, blur from astigmatism, or a cosmetic concern<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>Can drops cure it?<\/span><\/dt>
    No. Drops ease irritation and redness; only surgery removes the tissue<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>Surgery<\/span><\/dt>
    Removal with a conjunctival autograft is the standard operation; recurrence is about 5\u201310% with a graft, against about 80% when the growth is only cut away<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>Specialist<\/span><\/dt>
    Ophthalmologist with cornea and ocular-surface expertise; at Laser Istanbul Clinic, Do\u00e7. Dr. Muhammet Derda \u00d6zer<\/dd><\/dl><\/div>\n\t\t\t<\/div>\n\t\t<\/div><\/div><\/div><\/section>\n\n\n\n\n
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    What is a pterygium in the eye?<\/h2>\n\t\t\t\t\t\t\t\t

    A pterygium of the eye is a triangular, fleshy growth that begins in the conjunctiva at the limbus and creeps onto the clear cornea. The American Academy of Ophthalmology (AAO) describes it as fleshy tissue with blood vessels that can develop from a pinguecula and can expand to cover part of the cornea. Under the microscope, the tissue is degenerated and full of blood vessels, and as it advances it destroys the cornea’s thin front support layer, Bowman’s layer (EyeWiki).<\/p>\n

    Most people who have a pterygium notice it first in the mirror, as a pink or red triangle on the white of the eye pointing toward the pupil. It can affect one eye or both, and it is more often seen in one eye only. When people search for “pterygium eyes”, what they are looking at is almost always this: a sun-related growth on the surface of the eye, not an infection and not a tumour.<\/p><\/div>\n\t\t\t\t\t\t\t\t\t\t\t<\/div>\n<\/div><\/div><\/div><\/div><\/div><\/section>\n\n\n\n\n

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    Pterygium causes: why does it grow?<\/h2>\n\t\t\t

    The main pterygium cause is ultraviolet (UV) light.<\/strong> EyeWiki, the AAO’s clinical encyclopedia, names UV exposure as the primary risk factor. The AAO adds that both pterygium and pinguecula result from a combination of sunlight, wind and dust. The causes and the groups most at risk fit together:<\/p>\n\t\t\t

    Risk factor<\/th>What the evidence says<\/th><\/tr><\/thead>
    Sunlight (UV)<\/th>The leading cause; the growth is most common in hot, sunny regions near the equator<\/td><\/tr>
    Latitude<\/th>A 2013 meta-analysis in BMJ Open<\/em> found higher prevalence at lower latitudes (closer to the equator)<\/td><\/tr>
    Outdoor activity or work<\/th>In the same analysis, the pooled odds ratio for outdoor activity was 1.76<\/td><\/tr>
    Male sex<\/th>The same analysis gave an odds ratio of 2.32 for men; EyeWiki suggests this may reflect greater UV exposure<\/td><\/tr>
    Age<\/th>Prevalence rises with age, consistent with UV exposure building up over the years<\/td><\/tr>
    Wind and dust<\/th>Named by the AAO as contributing causes alongside sunlight<\/td><\/tr><\/tbody><\/table><\/div>

    In practical terms, farmers, builders, fishermen, sailors, drivers and people who live in hot, dry, dusty places such as the Gulf are the classic patients. A pterygium is not an infection and is not contagious.<\/p><\/div>\t<\/div><\/div><\/div><\/section>\n\n\n\n\n

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    Pterygium symptoms: what does it feel and look like?<\/h2>\n\t\t\t

    Many pterygia produce no symptoms at all. When symptoms do appear, the most common ones are:<\/p>\n\t\t\t

    Symptom<\/th>Why it happens<\/th><\/tr><\/thead>
    A visible pink or red, wing-shaped growth on the white of the eye<\/th>The tissue is full of blood vessels<\/td><\/tr>
    Redness and swelling of the white of the eye<\/th>Surface inflammation, often worse in wind, sun or dry air<\/td><\/tr>
    Dryness, itching, burning or a gritty, “something in my eye” feeling<\/th>The raised tissue irritates the surface of the eye<\/td><\/tr>
    Watering<\/th>Irritation of the surface<\/td><\/tr>
    Blurred or changing vision<\/th>The growth changes the shape of the cornea (induced astigmatism) or grows across the pupil area<\/td><\/tr>
    Concern about appearance<\/th>A red growth is visible, and some people want it removed for cosmetic reasons<\/td><\/tr>
    Limited eye movement (rare, advanced)<\/th>EyeWiki lists restricted eye movement among the reasons for surgery<\/td><\/tr><\/tbody><\/table><\/div>

    The key point for vision: a pterygium that stays at the edge of the cornea may not affect sight. Once it grows toward the centre, it can cause astigmatism and eventually cover the visual axis, so any growth that is getting bigger deserves a check-up.<\/p><\/div>\t<\/div><\/div><\/div><\/section>\n\n\n\n\n

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    Pterygium vs pinguecula: what is the difference?<\/h2>\n\t\t\t

    The difference between a pinguecula and a pterygium is whether the growth reaches the cornea.<\/strong> EyeWiki defines a pinguecula as a raised, yellow-white, non-malignant spot on the conjunctiva that does not involve the cornea. A pterygium, by contrast, crosses the limbus and extends onto the cornea. If you are searching “pinguecula vs pterygium”, this is the test the doctor applies.<\/p>\n\t\t\t

    <\/th>Pinguecula<\/th>Pterygium<\/th><\/tr><\/thead>
    Appearance<\/th>Yellowish, raised bump or patch on the white of the eye, usually near the nose<\/td>Pink or red, fleshy, wing-shaped growth with visible blood vessels<\/td><\/tr>
    Reaches the cornea?<\/th>No<\/td>Yes: it grows across the edge of the cornea<\/td><\/tr>
    Affects vision?<\/th>Usually not<\/td>Can, through astigmatism or by covering the pupil area<\/td><\/tr>
    Usual cause<\/th>Sunlight, wind and dust<\/td>The same causes<\/td><\/tr>
    Usual treatment<\/th>Lubricating drops; surgery is typically unnecessary (AAO)<\/td>Lubricating drops for irritation; surgery if it threatens vision, keeps irritating, grows or restricts eye movement<\/td><\/tr>
    Link between them<\/th>EyeWiki notes that inflamed pingueculae with a poorly lubricated surface may be a subgroup more likely to progress to pterygium<\/td>A pterygium can develop from a pinguecula (AAO)<\/td><\/tr><\/tbody><\/table><\/div>

    Two other things can look similar and should be ruled out by a doctor. A pseudopterygium<\/strong> is a scar-like band that attaches to the cornea after an injury or inflammation, and ocular surface squamous neoplasia (OSSN)<\/strong> is a rare surface tumour. Our sibling page explains the yellow spot in full.<\/p>

    Glossary: Pinguecula (yellow spot on the white of the eye) <\/svg><\/a><\/div><\/div>\t<\/div><\/div><\/div><\/section>\n\n\n\n\n
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    \"Close-up<\/div><\/div>\n\t\t
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    How is a pterygium diagnosed?<\/h2>\n\t\t\t\t\t\t

    A pterygium is diagnosed by looking at it: an eye doctor examines the eye with a slit lamp, a microscope with a bright, thin beam of light that shows the growth and how far it has crossed onto the cornea. Your surgeon will usually also:<\/p>\n\t\t\t\t\t\t