What’s Pterygium?OPHTHALMOLOGY BY ADMIN MARCH 24, 2017
A pterygium is a generally benign growth of fibroblastic tissue on the eye of an adult with chronic UV exposure. Pterygia can be unilateral or bilateral, are usually located on the nasal side, and extend to the cornea. Pterygia often require no treatment but can be removed surgically if they interfere with vision. Patients with dry eyes are prone to the development and progression of pterygia.
A pterygium is a proliferation of fibrovascular tissue on the surface of the eye, which extends onto the cornea.
The etiology of pterygium is incompletely understood; however, chronic UV exposure is accepted as a causative agent. Chronic inflammation and oxidative stress may also play a role in pathogenesis.
Pterygia have features seen in malignant tissues, such as normal tissue invasion and high recurrence rate.4 Pterygia can be associated with premalignant lesions.
Redness, itching, and/or irritation of the involved eyes (some are symptom free).
Visual blurring if the pterygium grows over the visual axis. Even if not obscuring the visual axis, the pterygium can cause poor vision by leading to irregular and high astigmatism.
Pterygia are diagnosed clinically by their distinctive appearance.
• Unilateral or bilateral.
• Nasal or nasal and temporal.
• Consider another diagnosis with a unilateral temporal distribution.
Pinguecula is a yellowish patch or nodule on the conjunctiva and does not extend onto the cornea.
Conjunctivitis is conjunctival injection with discomfort and eye discharge.
Squamous cell carcinoma of the conjunctiva is rare. Consider carcinoma when a unilateral growth is noted on the temporal side. Also, consider malignancy if there are grossly aberrant-appearing blood vessels on the surface of the eye. Patients with abnormal immune systems (e.g., cancer, HIV) are at particular risk for ocular surface malignancy.
Avoid sun exposure and use UV filtering sunglasses when sun exposure is unavoidable.
Nonprescription artificial tears and/or topical lubricating drops to soothe the inflammation. Ophthalmologists will occasionally prescribe a short course of topical corticosteroid anti-inflammatory drops when symptoms of the pterygia are more intense.
Pterygia are usually treated when they interfere with vision or when they cause significant irritation or pain. The standard therapy is surgical removal.
Pterygia have a high rate of recurrence. Conjunctival autografting and an antifibrotic treatment (e.g., mitomycin C) can be used intraoperatively to lower recurrence.
A nasal pterygium
Bilateral pterygia growing over the cornea
Pterygium that has grown onto the cornea but not covered the visual axis. This fibrovascular tissue has the shape of a bird’s wing (literal definition of pterygium). The small vessels are prominent in this view.
Pinguecula nodule on conjunctiva that does not extend to the cornea
Nasal pterygium growing over the visual axis in a man living close to the equator. The patient did not use sunglasses. The melanosis within the pterygium is benign.
A pterygium that has grown over the visual axis and is interfering with this person’s vision.