What is Glaucoma?

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Glaucoma is the second most common cause of blindness. According to the WHO it affects 60 million people worldwide, with this figure predicted to exceed 100 million in 2020 due to an ageing population. It is an optic nerve disease mainly caused by an increase in pressure inside the eye, which results in a progressive loss of peripheral vision. Glaucoma does not produce any symptoms until the individual losses their vision, which is irreversible, although its advance can be prevented if detected early. 

Glaucoma explained in first person

Professionals and patients explain how you live with the disease
There are 50% of cases that are not diagnosed. And the diagnosis is important to start a treatment as soon as possible that, we must not forget, is designed to preserve the vision that the patient still has.
My diagnosis was relatively easy because of family issues, our family history. My mother had it for many years, she lost her sight and following that, the family alarm went off.

Glaucoma is a group of eye diseases that damage the optic nerve and progressively reduce peripheral vision. The optic nerve is responsible for transmitting visual information from the eye to the brain.

Although any vision lost due to glaucoma cannot be recovered, with an early diagnosis, regular monitoring and treatment the condition can be controlled and further vision loss prevented.

Tipos de Glaucoma

Primary open-angle glaucoma

Primary open-angle glaucoma. The eye’s filter (filtration angle) is open, but it does not work very well, so the fluid in the eye (aqueous humour) does not drain away correctly. It is the most frequent type of glaucoma and it develops very slowly and practically without any symptoms.

Primary angle-closure glaucoma

Angle-closure glaucoma. The eye’s filter is closed and the aqueous humour does not have enough space to drain away from the front of the eye. This type of glaucoma is much less common and can occur slowly (chronic) or quickly (acute) with a rapid and painful increase in eye pressure.

Secondary glaucoma. In this case the condition is the result of another eye disease or trauma that affects the filtration angle. For example, it could be due to inflammation (uveitis), an excess of pigment (pigmentary glaucoma) or flaking inside the eye (pseudoexfoliation). Furthermore, secondary glaucoma can also be caused by the growth of new blood vessels (neovascularisation) inside the filter which prevent it from working correctly.

Pregnant woman with glasses

Congenital glaucoma. This is a very rare type, but it can be very severe. It is normally present at birth or develops shortly after birth. Congenital glaucoma is caused by a deformity in the structure of the eye.

How many people does glaucoma affect?

According to data from the WHO, glaucoma is the second cause of blindness worldwide (it is responsible for 12% of all cases of blindness) and the first cause of irreversible blindness. It is estimated to affect 60 million people and, due to population ageing, this number is forecast to increase by 45% by the year 2040 (111.8 million).

In our setting, glaucoma affects 2% of the population aged over 40 years. Recent studies estimate that there are around 1 million people with glaucoma in Spain, although approximately half of them are unaware they have the disease.

Substantiated information by:

Elena Fraga Pumar
Elena Milla Griñó
Marta Pazos López

Published: 19 October 2018
Updated: 19 October 2018

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