Pterygium is caused by degeneration, thickening, and hyperplasia of the bulbar conjunctiva and subconjunctival tissues in the eyelid fissure, which develops into the cornea in a triangular shape. The common people also call it “eye of the eye”, or “fish meat”. Many patients come to the hospital and say, “Look, I have a piece of fish in my eye, it’s ugly. Pterygium is usually found in the corner of the eye, and can sometimes grow into the black eye, blocking the pupil and causing vision loss. How does a pterygium develop? The cause of pterygium is still unclear, but it is generally believed to be related to long-term field work, exposure to sand, dust, cold, heat and sunlight. At the same time, overwork, lack of sleep and chronic inflammation of the conjunctiva are also triggering factors. Therefore the disease is common among farmers, drivers and people who work outdoors for long periods of time. The pterygium can be divided into 3 parts in terms of its morphology: the tip of the pterygium, also called the head, which grows on the black eye. The slightly elevated, fan-shaped part of the pterygium is located at the junction of the black and white eyes and is called the neck. The wide part of the pterygium that extends to the surface of the white eye is called the body, on top of which there are many new blood vessels. There are two types of pterygium: The first type is the resting type: the pterygium grows to the edge of the black eye and stops, it is not congested, its color is slightly red, the head is flat, the neck and the body are thin, and it is in a relatively resting state, but it does not fade on its own. It has no effect on the patient other than aesthetic. The second type of pterygium is the progressive type: the pterygium is congested, hypertrophic, with increased neovascularization and an elevated head that grows into the surface of the black eye. There is another type of pterygium, called pseudopterygium, which can grow on any part of the edge of the black eye and is usually small and grayish in color, but there are also thicker ones. It is often due to trauma, ulceration of the corneal limbus, and chemical or thermal burns of the conjunctiva forming scar tissue, which usually does not grow again after formation. It is completely different in nature from the two types of pterygium we talked about earlier. 1. Treatment So what should I do if I have a pterygium? Generally, you should go to the hospital for examination and treatment. First, medication is usually used for the static type of pterygium, but if the pterygium does not grow into the black eye and does not affect vision, treatment is not necessary. If there is a combination of trachoma or chronic conjunctivitis, antibiotic eye drops or hormonal eye drops can be applied to the eye to eliminate inflammation and slow down the development of the pterygium. In contrast, for early progressive pterygium, we can treat it with argon laser or local injection of Pingyangmycin. This will avoid the pain caused by surgery, but once the pterygium grows into the corneal tissue and bulges, it should be surgically removed as soon as possible. If you wait until the pterygium grows to cover the pupil before surgery, the first postoperative recurrence rate will be greatly increased, and the surgical removal of the pterygium will result in scarring of the cornea, making it opaque and affecting the recovery of vision. The recurrence rate of pterygium after simple excision surgery according to the traditional method in the past is high, generally about 30% to 40%. This means that 3 to 4 out of 10 people will recur after surgery. The stimulation of surgery causes chemotaxis and aggregation of polymorphonuclear leukocytes, which can release vascular growth factors, and this is the reason for neovascularization and recurrence after surgery. Because of the high incidence of pterygium and the high recurrence rate after surgery with the traditional surgical approach, the ophthalmology community has conducted intensive research on this procedure and has continued to improve and refine the surgical approach. Nowadays, we mostly use microscopic excision of pterygium plus self-conjunctival flap grafting, which completely removes the pterygium and smooths the corneal surface of the excised area, and then performs self-conjunctival grafting, which eliminates the stimulating factors that produce neovascularization, thus stopping the recurrence of pterygium. In addition, we generally use mitomycin eye drops for 1 to 2 weeks after surgery to inhibit the proliferation of DNA and fibroblasts, which also greatly reduces the recurrence of pterygium. Also during the treatment period, patients should adhere to the medication, review regularly, eat less spicy and irritating foods such as chili and onion, and should avoid smoking and alcohol, which can reduce the postoperative inflammatory response and reduce the recurrence of pterygium. 2, Prevention of pterygium is a common disease in ophthalmology, how can we prevent the occurrence of pterygium? Here I would like to give you a few suggestions: we should avoid smoke, dust, sand and sunlight as much as possible, reduce ultraviolet radiation, wear sunglasses when going out, pay attention to eye hygiene, treat trachoma or other types of conjunctivitis in a timely manner, and pay attention to adequate sleep, regularity of life, and avoid dry stools and other general conditions, which can greatly reduce the occurrence of pterygium.