A pinguecula (plural: pingueculae) is a yellowish, slightly raised thickening or growth on the conjunctiva, the thin translucent membrane that covers the white part of the eye. It typically occurs on the part of the conjunctiva most exposed to the sun, ie, between the upper and lower eyelids. It appears close to the edge of the cornea, the clear front covering of the eye, but does not involve it. It is a non-cancerous condition and may involve one or both eyes. It is more common in middle-aged or older people.
The exact cause of a pinguecula is unknown. However, it is frequently associated with long-term exposure to ultraviolet (UV) rays from sunlight as well as wind or dust. It is therefore common among people who spend a considerable amount of time outdoors, particularly in very sunny environment without UV protection such as sunglasses or hats.
Usually pinguecula causes no symptoms but some patients may experience:
- Irritation
- Foreign body sensation
- Redness
- Itch
- Dryness
Although a pinguecula can often be seen with the naked eye, an eye care professional usually diagnoses the condition after a careful examination under high magnification using an instrument called a slit-lamp biomicroscope. The slit-lamp also allows the eye care professional to measure the size of the pinguecula and to look for associated problems such as inflammation.
No specific treatment is necessary when a patient does not have any symptom other than the presence of the pinguecula. If the pinguecula becomes inflamed or causes irritation, treatment may involve using artificial tears or gel for lubrication and a short course of steroid eye drops to reduce the inflammation.
In most cases, surgical removal of a pinguecula is not needed. Surgical removal may be considered when a pinguecula becomes a cosmetic blemish or when it interferes with contact lens wear or blinking.
Pinguecula may lead to the formation of pterygium (plura: pterygia), a localised growth in the eye that can invade the cornea and threaten vision.
Individuals can reduce the risk of developing pinguecula by protecting their eyes from harmful UV rays with sunglasses, umbrellas or hats. Protection from wind and dust are also thought to be helpful.