Pterygium surgery has come a long way since it was first described by a physician named Sushruta from India way back in 1000 BC. Now we know a little bit more about this fibrovascular, wing-shaped growth crossing from the white sclera to the transparent cornea of the eye, including how to treat it.
Does a Pterygium Always Need Surgery?
A pterygium is considered to be a benign growth (though does share some similar characteristics to a type of cancer called ocular surface squamous neoplasia). For this reason, it is never an absolute life-saving necessity to undergo pterygium surgery, but there can be some compelling reasons for you to consider it.
As it progresses, a pterygium may:
- Not look great
- Become frequently red and inflamed
- Interfere with your sight, such as causing double vision
Not everyone with a pterygium will get to a point where it becomes problematic. But if that fleshy triangular overgrowth on your eye is concerning, the first step would be to find yourself a pterygium surgeon.
Types of Pterygium Surgery
A few different approaches to pterygium removal have developed over the years. Despite their differences, they are all unified in two goals: to get rid of that pesky pterygium and to minimize the risk of it ever coming back (that is, recurrence).
Bare sclera technique
The bare sclera technique is exactly as it sounds – strip off that pterygium and leave the bare sclera behind to heal on its own. Unfortunately, while the bare sclera technique for pterygium surgery achieves the first goal of removing the pterygium, it often fails miserably at the second, with recurrence rates reported as high as 89%.
Amniotic membrane transplant (AMT)
An amniotic membrane is a piece of tissue taken from a donor human placenta. Having such a piece of tissue placed on your eye might sound unappealing, but consider donor organs and even donor corneas – same, same. An AMT starts with surgically cutting off the pterygium, but then covers the wound with the amniotic membrane, which may be glued or sutured in place. The membrane supports faster healing and lower recurrence rates compared to the bare sclera technique.
Pterygium excision with mitomycin-C
Mitomycin C is a potent medication used in a number of different treatments, including for cancer. In the context of pterygium surgery, it is used as an add-on treatment to suppress cell growth and prevent the pterygium from returning. Though mitomycin C may be effective at reducing recurrence, it also carries some risks of damaging surrounding tissue due to its toxicity.
With the exception of the bare sclera technique, these approaches to pterygium surgery are used often in modern ophthalmology. But there’s one more player in this game.
What is a Conjunctival Autograft?
A pterygium excision with conjunctival autograft is one of the more common methods for managing a bothersome pterygium. This technique takes a section of healthy conjunctiva (the transparent membrane that covers the white sclera) from your own eye to bandage the wound left by the pterygium removal. This conjunctival tissue is usually taken from the whites of your eye beneath your upper eyelid, and then sealed in place either with a medical-grade adhesive called fibrin glue or with tiny stitches.
The advantages of conjunctival autografting for pterygium are several-fold:
- Gets rid of the pterygium via excision (first goal: check)
- Avoids the problem of tissue rejection since the graft came from your own eye
- Accelerates post-op healing
- Associated with pterygium recurrence rates as low as 2 up to 15% (second goal: check)
Pterygium surgery with conjunctival autograft is widely considered to be the gold standard and preferred approach. It avoids the risks that come with using a medication as toxic as mitomycin C and delivers a lower risk of recurrence than AMT.
Conjunctival autografting also is associated with few complications. If complications do arise, they are typically minor, such as the graft becoming dislodged or wrinkled.
However, this approach isn’t a one-size-fits-all. Your pterygium surgeon may recommend one of the other techniques such as AMT if you don’t have enough healthy conjunctival tissue to spare, or have another eye condition affecting the integrity of your conjunctiva. A consultation with Dr Michel can provide clarity around whether pterygium surgery with conjunctival autografting is right for your situation.