Pterygium and pinguecula are a degeneration of the conjunctiva, the transparent membrane that covers the surface of the eye. They typically appear in areas exposed to the area between the upper and lower eyelids and are most common on the nasal side. 

A pinguecula manifests itself as a small white or yellowish bump just beside the cornea, which may be flat and triangular or more raised and round. However, if this bump or abnormal growth extends beyond and invades the cornea, it is called a pterygium.

A generally triangular-shaped tissue can be observed. It grows on the edge of the cornea with the apex towards the centre. The corneal invasion may be larger or smaller depending on the progression. In some regions of Spain, it is called a "palmera" (palm tree). 

The main causes of this type of degeneration are UV rays from the sun and the wind. For this reason, this pathology is more common among inhabitants of tropical countries. People who work in the open air like fishermen and farmers are at greater risk of pinguecula and ptyergium.

Age plays an important role in the development of pterygium. The younger the patient, the higher the risk of the pinguecula invading the cornea and becoming a pterygium and the higher the risk the pterygium has of growing. If the tissue of the pinguecula or pterygium is fleshy and thick, there is a higher chance of it growing than if the tissue if flat and membranous. 

Generally, this pathology does not have symptoms except in the case of pinguecula, the patient will have a white-yellow tissue or lump in the white part of the eye and, in the case of pterygium, the patient will have a white tissue invading the cornea. If the lump is very raised, it may cause discomfort whenever the patient blinks. When there is irritation, both pingueculas and pyterygiums become inflamed causing mild discomfort, the sensation of grit or a foreign body in the eye and redness in these areas.

The way to prevent these pathologies and stop them from growing and becoming inflamed is to stop your eyes from being exposed to the sun or the wind. Protecting your eyes using sunglasses that cover the sides fully is extremely important, especially in summer and in areas with a high level of UV light, such as the beach, the sea or the snow, or where there's a lot of reflection from the sun. 

The use of artificial tears helps to lubricate the eye surface and alleviate the annoying symptoms. If the pinguecula and pterygium become inflamed and red, the use of a topical corticoid monitored by an ophthalmologist is indicated. 

Pinguecula does not require surgical treatment. That said, if it is causing discomfort to the patient or becomes inflammed frequently despite preventive measures, surgical removal is indicated. The patient's aesthetic appearance is also an indication for surgery.  

The pterygium is removed surgical whenever it invades the cornea more than 2 millimetres, a size that threatens to take up the central area of the cornea, invades the visual axis and may affect the vision. If it is smaller, pterygium surgery is not required unless it causes discomfort, if it is often inflamed or for the patient's own aesthetic reasons. 

There are various techniques for removing the pterygium. The most commonly used technique at present is pterygium removal with full cleaning of the tissue in the area, and the transplant of a healthy conjunctiva obtained from another area of the eye, usually the upper area.

If the pterygium is recurrent and the conjunctiva has been used in previous operations and there is no healthy conjunctiva available to transplant, the amniotic membrane or buccal mucosa may be used to cover the area where the degenerative and scar tissue has been removed. In cases with a greater risk of recurrence, drugs that inhibit scarring like Mitomycin C can be used in the procedure, although it may have undesirable side effects.