Pterygium - Prevention, cause, symptoms and treatment

Pterygium

Pterygium is fleshy conjunctival membrane growth (has blood vessels) that cover the white area of the eye and slowly spread over the cornea. This growth is a kind of triangular shape. It may occur in one eye or both eyes. If it develops in both eyes called bilateral pterygium. Early-stage of pterygium is looked like pingecula, so sometimes it is difficult to differentiate between pterygium and pingecula.

Pterygium is a non-cancerous growth; sometimes this may disconfigure the eye cosmetically. Due to moderate to advanced pterygium growth person may experience redness, irritation, discomfort, and blurry vision. Pterygium grows very slowly but in very few cases it may grow rapidly.
Reason for occurrence - cause for pterygium occurrence is unclear. It could be due to overexposure to Ultraviolet rays, excessive exposure to dust and pollution. In case of dry eyes pterygium may increase. In case of injury or burn near black eyeball or its adnexa will also cause pterygium occurrence.

Stages of Pterygium

Stage 0: In this stage very small elevation appears near the black eyeball over the sclera. In this stage there is no vascularisation and conjunctival and corneal ectasia are seen.
Stage 1: In this stage small bump like mass touches the limbus.
Stage 2: In this stage bump flatten a little just on the limbus with minimal vascularisation.
Stage 3: In this stage the fleshy layer covers the area between the limbus and pupillary margin with minimal congestion and vascularisation. This stage is associated with mild to moderate astigmatism.
Stage 4: In this stage the fleshy layer reaches to central to the pupillary margin with severe congestion and dilation. This stage is associated with an increase in astigmatism and rarely leads to the limitation of eye movement.

Signs and Symptoms

Pterygium causes redness, itching, irritation, foreign body sensation, sometimes dryness in the eyes. Redness may increase when someone is exposed to air, dust, and pollution or drives without protective glass. Contact lens users may find discomfort due to poor fitting of contact lens in moderate to advanced pterygium conditions. The cosmetic appearance of the eye may not look good in the case of pterygium. Pterygium is stretching the front surface of the eye (cornea), which leads to astigmatism and higher-order aberrations which affects the quality of vision.

Treatment and prevention

• Avoid eye rubbing excessively.

• To wear protective glasses (covering full eyes).

• UV light protected glasses.

• Lubricants (eye moisten drops).

• Surgically (in case of moderation or advanced pterygium) - But recurrence rate is 2-5% after pterygium surgery. 

There are different techniques to remove pterygium surgically:
a. Pterygium excision with autologous conjunctival autografting
b. Pterygium excision with mitomycin C,
c. Pterygium excision with conjunctival limbal autograft
d. Pterygium excision with amniotic membrane transplantation

During the pterygium surgery fleshy mass is removed and replaced with a graft of associated membrane tissue to prevent recurrent pterygium growths. And this graft is attached either with sutures or fibrin glue, post pterygium surgery eye experienced lesser discomfort, and recovery time reduces with fibrin glue. But fibrin glue is having its own risk of transmitting infection (viral) and more inflammation.

Recovery time

Post pterygium surgery redness, irritation, foreign body sensation, and graft dissolving usually takes 6-8 weeks but this healing time may change due to the type of technique used during surgery.