Are you experiencing unusual changes the appearance of the eye?
Pterygium is a triangular fold of tissue that goes from the conjunctiva of the eye to the cornea. It is to be distinguished from pinguecula, yellowish raised bumps on the eyeball. In some cases, it has only mild effects and may not require any treatment, or merely eyedrops to soothe the feeling that there is a foreign object in the eye. However, in more severe cases there are a couple of reasons why individuals might seek surgical treatment. In one instance, the individual simply cannot tolerate the cosmetic aspects of the pterygium, including inflammation and reddening of the eye (see photo). In other instances, it encroaches on the individual’s vision or interferes with ocular motility and must be dealt with. Specifically, in addition to growing over the cornea and blocking the patient’s vision, it can change the shape of the front of the eye, which can lead to problems like astigmatism. However, surgery can also increase astigmatism in some cases (which can be treated with Intacs implants).
Pterygium is sometimes called “surfer’s eye” because the risk factors for it include exposure to UV light and sand. It is more common in people near the equator. Advanced age can also lead to pterygium, and dry eye disease. You may be at increased risk if you have light skin and light eyes.
Surgery removes the pterygium, and usually takes less than 30 minutes. The doctor may prescribe steroid eye drops for several weeks afterward. Inflammation and scarring can interfere with healing and threaten the patient’s sight. Furthermore, the pterygium can recur. Leaving the sclera uncovered can lead to a recurrence rate as high as 88%. Therefore, surgeons can turn to conjunctival autograft or amniotic membrane graft to cover the wound.
Surgeons are still exploring the ideal method of surgery and healing for psterygium. New techniques for removal and grafting are being developed. One technique has the acronym PERFECT: Pterygium Extended Removal Followed by Extended Conjunctival Transplantation. This is a conjunctival autograft that, as opposed to traditional conjunctival autografting, removes Tenon’s layer, (Tenon’s capsule, fascia bulbi) a thin membrane which envelops the eyeball from the optic nerve to the corneal limbus . This procedure reduces recurrence and poor cosmetic outcomes.
Doctors are also increasing considering amniotic membrane for healing. As discussed in previous articles on symblepharon, amniotic membrane has great anti-inflammatory properties. It can prevent scarring because it prevents proliferation and myofibroblast differentiation. Amniotic membrane is harvested from consenting mothers after healthy caesarean section is extensively tested to prevent disease transmission. Generally, it is cryopreserved. This method is favored despite the short shelf-life of the resulting product because it preserves the best qualities of the amniotic membrane including its active components. Amniotic membrane also has an analgesic effect which is preferable to an autograft that can cause some pain and discomfort and complicate future surgeries. Amniotic membrane may eliminate the pain from the pterygium as well. Recurrence rates using amniotic membrane have been shown to be extremely low.