(See also Overview of Conjunctival and Scleral Disorders Overview of Conjunctival and Scleral Disorders The conjunctiva lines the back of the eyelids (palpebral or tarsal conjunctiva), crosses the space between the lid and the globe (forniceal conjunctiva), then folds back on itself as it spreads... read more .)
A pinguecula is a raised yellowish white mass within the bulbar conjunctiva, adjacent to the cornea. It does not tend to grow onto the cornea. However, it may cause cosmetic blemish or irritation if elevated due to inflammation and, although rarely necessary, can easily be removed and will typically not recur.
A pterygium is a fleshy triangular growth of bulbar conjunctiva, occurring only at the 3 and 9 o'clock meridians of either eye, usually not simultaneously. The pterygium may spread across and distort the cornea, induce astigmatism, and change the refractive power of the eye. Symptoms may include decreased vision and foreign body sensation. It is more common in sunny, hot, dry climates.
To relieve symptoms caused by a pterygium, artificial tears or a short period of treatment with corticosteroid drops or ointments may be prescribed. Growth of the pterygium may be slowed by the use of a hat that shields the eye from ultraviolet (UV) sunlight and UV block in glasses and sunglasses. Removal is often indicated for documented growth, cosmesis, to reduce irritation, and to improve or preserve vision. Antimetabolites such as mitomycin and 5-fluorouracil (5-FU) have been used effectively—intraoperatively and postoperatively—to decrease recurrence rates, but they have a high complication rate, including scleral and corneal melting. Subconjunctival injections of anti-VEGF (bevacizumab) beneath a pterygium may be useful to prevent progression and improve outcomes when used with pterygium excision plus graft, and for recurrent pterygium. The technique with the best results to prevent recurrence is surgical removal of the pterygium followed by conjunctival autograft.
Pinguecula and pterygium
Pinguecula and pterygium are conjunctival growths that may result from chronic actinic irritation. Pinguecula (left) is accumulation of conjunctival tissue at the nasal or temporal junction of the sclera and cornea. Pterygium (right) is conjunctival tissue that becomes vascularized, invades the cornea, and may decrease vision due to obstruction or induced astigmatism.