9 February 2021 Author : Cláudia Bacalhau What is the pterygium A pterygium is an abnormal growth of the conjunctiva along the surface of the cornea , usually from the nasal side towards the center of the eye (pupil). It resembles a "skin" that grows on the surface of the eye. Pterygium is more common in countries with a hot climate, and is associated, among other factors, with exposure to ultraviolet radiation (UV) and chronic dryness of the ocular surface. Symptoms and diagnosis Many cases of pterygium are asymptomatic, especially when lesion is small. When symptoms are present, the most common are irritation , burning , dryness or foreign body sensation . Occasionally, the pterygium can become inflamed and lead to hyperemia (dilated vessels and red eye) and edema. Pterygium develops symptoms more often in people wearing contact lenses. Depending on the length of the pterygium , it can be classified by the ophthalmologist as: Grade 1 when it invades the cornea in less than 2 mm; Grade 2 when it invades the cornea between 2-4 mm; Grade 3 when the corneal invasion is greater than 4 mm towards the pupil. In the diagnosis it is necessary to differentiate the pterygium from: Pseudopterygium : burns or acute chemical lesions of the cornea often develop a pseudopterygium, with the formation of a conjunctiva band that covers the injured area. In this case of scar response, the pseudopterigen is strongly adhered to the ocular surface. Pinguecula : this is also a degeneration of the conjunctiva, which generally affects both eyes, with the appearance of a small yellowish-white mass of the conjunctiva next to the limbus (transition zone between the cornea and the sclera). It is also more frequent on the nasal side of the eye, but, unlike the pterygium, it does not invade the cornea. Treatment of pterygium Medical treatment The treatment of pterygium with drugs aims to resolve the symptoms (symptomatic treatment). It involves tear substitutes to improve comfort, for example sodium hyaluronate eye drops. When there are episodes of inflammation, short cycles of topical anti-inflammatory drugs are performed. Prolonged solar eviction and eye protection with glasses with an ultraviolet filter is recommended. Surgical treatment Surgical treatment may be indicated : For grade 3 pterygium or accelerated growth of the pterygium; Visual acuity impairment, usually by causing secondary irregular astigmatism; Symptoms of persistent discomfort; Aesthetic issues. The purpose of surgical treatment is to remove the pterygium . The surgery is performed under local anesthesia, on an outpatient basis (without the need for hospitalization) and is a short procedure. There are several surgical techniques to remove the pterygium, the main three are: Simple excision , in which the pterygium is scraped and cut, with simple closure of the conjunctiva. It has a high rate of recurrence, with a pterygium much more aggressive than the initial injury; Excision with conjunctival autotransplant , which is removed from the opposite side of the same eye and applied to the location where the pterygium was. This is the most commonly performed technique today, and is associated with a low recurrence rate; Excision with application of mitomycin-C , which inhibits recurrences and is used mainly in reoperations and refractory cases. In complex cases, other surgical options may be considered, for example with use of amniotic membrane, peripheral lamellar keratoplasty, among others. Remember A pterygium is a benign lesion, but it can cause eye, visual or aesthetic discomfort. Always consult your ophthalmologist to confirm the diagnosis and decide the best therapeutic options for your case. Meet the ophthalmology team from Hospital da Luz network. The content published in the Health Guide is intended for the general public and is provided for informational and educational purposes only. It does not replace individual medical assessment, diagnosis, or personalized clinical advice from a qualified healthcare professional. The content is produced or reviewed by physicians and other healthcare professionals at Hospital da Luz and is based on the knowledge available at the time of publication or the most recent update, as indicated at the beginning of each item.
