A pterygium is an abnormal, noncancerous growth of the conjunctiva. The conjunctiva is a thin membrane lining the inside of the eyelid and part of the eyeball. It is located between the sclera, or the "white of the eye" which surrounds the eyeball, and the cornea, the dome-shaped window covering the front of the eye which is responsible for the refraction of light. If a pterygium continues to grow, it may spread onto the cornea.
Excessive growth of the conjunctiva leads to a pterygium. The exact cause of pterygium is unknown.
Pterygium is more common in men and in those of increasing age. Other factors that may increase your chance of pterygium include:
Excessive exposure to environmental conditions (sunlight, dust, dirt, heat, dryness, wind, smoke) due to
- Outdoor hobbies
- Work in occupations with excessive exposure to solvents or chemicals
- Family members with pterygium
The symptoms of pterygia vary from person-to-person. It appears as a fleshy spot—whitish in color and containing blood vessels—extending onto the surface of the eye. In some people, pterygia remain small and do not affect vision. These pterygia are noticed only because of their abnormal cosmetic appearance. In other people, pterygia grow quickly and large enough to eventually distort the corneal surface and cause severely blurred vision. Pterygia do not cause pain.
Pterygium may cause:
- Sensation of something in the eye
- Blurred vision
Your eye doctor will ask about symptoms and medical history. An eye exam will be done.
Tests may include the following:
- Visual acuity—to measure your ability to see an eye chart
- Slit lamp examination—a bright light with magnification used to view the eye
- Corneal topography—a computerized test that maps changes to the curvature of the cornea
- Photo documentation—photography to record the degree of growth of a pterygium
The main goals of treating a pterygium are to:
- Prevent progression, inflammation, and infection
- Aid in the healing process, if surgery is performed
Treatment options include:
Your doctor will schedule periodic eye exams to monitor the pterygium. If symptoms increase, additional treatments may include:
Medications to treat pterygium may include:
- Prescription topical antibiotics to prevent infection
- Topical corticosteroids to reduce inflammation
- Ocular lubricants, such as artificial tears
If vision becomes severely blurred, the pterygium may need to be surgically removed. This is commonly done on an outpatient basis. On occasion, a pterygium can return. Steps may be taken during the operation to prevent this from happening.
In rare cases, a pterygium causes serious scarring of the cornea. If this happens, a corneal transplant may be needed. Once the pterygium has been surgically removed, medication may be used to aid in healing and prevent recurrence.
To help reduce your chance of pterygium:
- Wear dark glasses with UV protection to shield the eyes from sun, dust, and wind
- Avoid harsh environmental factors to slow the growth or regrowth of pterygium
American Optometric Association
Eye Smart—American Academpy of Ophthalmology
Canadian Ophthalmological Society
Coday M. Pterygium. Digital Journal of Ophthalmology website. Available at: http://www.djo.harvard.edu/site.php?url=/patients/pi/426. Accessed July 21, 2009.
Corneal disease—Pterygium and Stevens-Johnson syndrome. Washington University Physicians website. Available at: http://wuphysicians.wustl.edu/page.aspx?pageID=516. Accessed November 11, 2010.
Jurgenliemk-Schulz IM, Hartman LJ, Roesink JM, et al. Prevention of pterygium recurrence by postoperative single-dose beta-irradiation: a prostpective randomized clinical double-blind trial. Int J Radiat Oncol Biol Phys.2004; 59:1138-1147.
Kellogg Eye Institute. Pterygium. Kellogg Eye Institute, University of Michigan website. Available at: http://kellogg.umich.edu/patientcare/conditions/pterygium.html. Accessed August 12, 2005.
Sowka JW, Gurwood AS, Kabat AG. Handbook of Ocular Dsease Management. New York, NY: Jobson Publishing Co; 2001.
Last reviewed December 2014 by Michael Woods, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.