Prevention of Blindness and Visual Impairment

Priority eye diseases



Glaucoma can be regarded as a group of diseases that have as a common end-point a characteristic optic neuropathy which is determined by both structural change and functional deficit. The medical understanding of the nature of glaucoma has changed profoundly in the past few years and a precise comprehensive definition and diagnostic criteria are yet to be finalised. There are several types of glaucoma, however, the two most common are primary open angle glaucoma (POAG), having a slow and insidious onset, and angle closure glaucoma (ACG), which is less common and tends to be more acute.


The number of persons estimated to be blind as a result of primary glaucoma is 4.5 million, accounting for slightly more than twelve per cent of all global blindness. Risk factors are those limited to the onset of disease and those associated with progressive worsening in already established disease. The primary risk factors that are linked to the individual and the onset of the disease are age and genetic predisposition. The incidence of POAG rises with age and its progression is more frequent in people of African origin. ACG is the common form of glaucoma in people of Asian origin.

Prevention and treatment

There is little known about primary prevention of glaucoma; however, there are effective methods of medical and surgical treatment if the disease is diagnosed in its early stage. Through appropriate treatment, sight may be maintained; otherwise the progression of the condition leads eventually to severe restriction of the visual field and irreversible blindness.

VISION 2020 role

As the majority of cases of glaucoma can be effectively managed, it is desirable to include this condition in VISION 2020 national plans. This is particularly appropriate in countries and regions where some of the 5 principally targeted eye conditions are not a public health problem, and more resources and attention can be dedicated to this eye disease.