Hyperopia

When colloquially farsightedness called hyperopia (synonym: hypermetropia or hyperopia ) is a so-called axial refractive errors of the eye ( ametropia ), in which the eyeball is too short or the refractive power is too low in relation to the refractive power of its optical device. This leads to the fact that the image position ( focal point) for optically infinitely distant object is not in a relaxed (not akkommodiertem ) eye in the retina level, and thus is not an essential element for a sharp visual impression. Instead, the ( virtual ) focal point in the far-sighted eye behind the retina, and the result is a blurred visual impression. The closer an object is introduced to the eye, the further shifting the focal point to the rear. The result is an aberration which nearby objects can appear blurred as far away - so the person (hence the term " far - sighted " ) sees in the distance better than nearby. The degree of hyperopia is determined by refraction and expressed in diopters.

Hyperopia is primarily genetic. While many forms of congenital abnormalities of the eyeball associated with hyperopia, hyperopia, the no disease alone, but a variant of the normal eye development dar.

Hyperopia, accommodation and presbyopia

A low or moderate hyperopia is usually involuntarily so compensated by increasing the refractive power of the eye lens (accommodation) that they will not initially noticed by the affected people. So as long as a pain-free vision at distance and near is possible hyperopia does not need to be corrected. In children, hyperopia part of the development process. In general, it is reduced in the course of growth ( see chart). Higher grade hyperopia than three diopters (D ). but should also in childhood - to be corrected, otherwise there may be a risk of strabismus disease - at least partially.

However, the accommodative response decreases with increasing age and reached depending on the degree of hyperopia, usually between the ages of 35 and 45 a value that is no longer sufficient for sharp vision, first in the vicinity and later also in the distance. This physiological presbyopia ( presbyopia ) do not so noticeable earlier than in those with no hyperopia. If problems in the area caused by the decreasing accommodative power of the lens, the correction of hyperopia initially causes an improvement in near vision, but also a general relief of accommodation - even when looking into the distance. Later, when further increasing presbyopia, an additional near correction is required.

Treatment options

Necessary for the correction of hyperopia convex spectacle lenses or contact lenses have a positive refractive power and a " " sign in front of the specified strength in diopters. In recent years it has become possible for adults to be treated with a surgical procedure by means of refractive surgery.

Already a undercorrected hyperopia may occur due to necessary to compensate for accommodation in childhood lead to an esotropia. Therefore an important component of therapy represents an optimal spectacle correction dar. This happens less in order to improve visual acuity, but rather to reduce the tendency of a squint disease. It is not uncommon when such prescription glasses does not cause significant subjective improvement in visual acuity. However, this does not negate the need to wear the prescribed correction anyway. Severe hyperopia in childhood should be a precaution corrected with glasses also attenuated in normal binocular vision and sufficient amplitude of accommodation, at the latest when the visual loads with the enrollment increase.

The common before the invention of the intraocular lens without replacement surgical removal of the eye lens in lens opacities (cataracts ) leads to a hyperopic shift by about 13 diopters and made at that time cataract glasses required.

Etymology

The medical terms hyperopia and hypermetropia are derived from the ancient Greek ὑπέρ hyper " on " (or ὑπέρμετρος hypérmetros "excessive" ) and ὤψ ops "eye" from.