Diseases

Hypermetropy: the causes

The cause of hyperopia is an axial length of the eye "too short" to receive the image clearly. The image received by the eye is focused in a plane located behind the retinal plane: as the image is defocused, it is perceived as fuzzy.

In children, severe hyperopia may be due to immaturity of the eye. In non-presbyopic patients, the vision abnormality of hyperopia can be "self-corrected" by the tuning eye. This accommodation effort is used to improve vision from a distance. To see clear in the distance, the farsightedness therefore accomodates permanently, and to see net close, it must accommodate even more. There is therefore an over-use of accommodation, a mechanism normally used to see closely.

It is because of this that the hyperopic worsens with presbyopia. Before that, the symptoms, specifically the decline in vision, are noticeable. Indeed, the progressive loss of accommodation related to presbyopia makes it more and more difficult to compensate for this optical defect. This is why close vision can be difficult early in life, in the farsighted: the sooner that hyperopia is important. Hyperopia and presbyopia worsen each other and hinder near vision.

Astigmatism, myopia, hyperopia ... vision disorders explained in pictures!

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