Hypermetropia

Hypermetropia, along with astigmatism and myopia, belongs to the group of ametropias (disorders relating to the refraction of the eye), i.e. it is a vision defect.

In hypermetropia the focus of the images does not fall on the retinal plane (as it does in the normal eye), but beyond it, causing blurred vision. In mild forms of hypermetropia, blurred vision only affects near objects, whereas in severe forms it also affects distance vision.

Dioptres are the unit of measurement for defining the extent of hypermetropia: greater hypermetropia requires lenses with greater dioptric power to correct it.

In the case of young people with mild hypermetropia, the eye is able to correct this sight defect by itself through a physiological mechanism that changes the crystalline lens known as “accommodation”. With advancing age, or for greater degrees of hypermetropia, however, this process may no longer be sufficient and external help must be sought from corrective lenses to achieve clear vision.

The most common symptoms associated with hypermetropia therefore vary depending on both the extent of the defect and the age of the patient. In general, they include:

• blurred vision at close range;
• redness and burning of the eyes;
• headaches;
• hypersensitivity to light (photophobia);
• excessive tearing of the eyes.

It is very important to have regular check-ups at an ophthalmologist from an early age and, if this vision defect is detected, to correct it as soon as possible to reduce the symptoms described. Indeed, especially in children, proper correction of hypermetropia can prevent the development of amblyopia (lazy eye) and certain types of strabismus.