Ophthalmology

Farsightedness

Synonyms in a broader sense

Clarity, hyperopia, hypermetropia, presbyopia, presbyopia
Astigmatism, myopia

English: Longsightedness, Hyperopia, Hypermetropia

definition

In farsightedness (hyperopia) there is an imbalance between the refractive power and the length of the eyeball.
Far-sighted people see well in the distance, but objects appear blurry up close. The eyeball is too short in relation to the refractive power (Axis hyperopia) or the refractive power is too weak in relation to the eyeball (Refractive hyperopia).

root cause

The Axial hyperopia (axes - farsightedness) is much more common than refractive hyperopia (Refractive farsightedness) and almost always innate. Either it is a malformation of the eyeball or it has simply grown a little too short. In some cases, especially in severe farsightedness (hyperopia), it can also be inherited.

In the Refractive hyperopia it is mostly the so-called Lenslessness, where the Eyes - lens completely missing. Another cause can be a dislocated lens (aphakic hyperopia), in which the lens is not in its natural place (lens dislocation). The refractive power is then not completely canceled because it is about two thirds of the Cornea accomplished. However, a person with no lens can no longer accommodate (focus on objects).

Disease emergence

In farsighted people, the incident light rays meet at the focal point behind the lens.

In farsighted people, the focal point becomes parallel to rays entering the eye Behind of the Retina pictured. However, in order to be able to depict objects sharply, the focal point exactly on the retina. With the help of the lens man is able to Focus to change in a certain range between near and far.
This process, more precisely the focusing from a distance on nearby objects, is also called Accommodation. This property is best developed in childhood and decreases with age due to a loss of elasticity in the lens. The so-called phenomenon then occurs Presbyopia (Presbyopia).

Adolescents can compensate for low or moderate farsightedness through their ability to accommodate by increasing their level of accommodation. This has two consequences: On the one hand, farsightedness may only be noticed at a later age and, on the other hand, the chronically increased accommodation leads to the muscle that is responsible for accommodation (Ciliary muscle), get used to it over time and can no longer relax completely (accommodation spasm). This form of farsightedness is then also called latent hyperopia (undetected farsightedness)

In adolescents, it accounts for about half, and in middle age it accounts for a quarter of total farsightedness. Only if a farsighted youngster pays attention to it as often as possible glasses / Wearing contact lenses can partially relax the ciliary muscle again over time.

The other part of farsightedness that cannot be compensated and therefore cannot be corrected with glasses or contact lenses is called manifest hyperopia (permanent farsightedness)

The strength of the ametropia is in Diopters (dpt) specified. That is the reciprocal of the focal length. The values always refer to the far point. This is exactly the point at which the eye images sharply without accommodating, i.e. is completely relaxed. With normal sighted people this point is at infinity. With the farsighted one, it is virtual and is behind the eye.

Danger glaucoma

Due to the increased accommodation (increased flattening of the lens) and the resulting flatter anterior chamber, this is more common in farsighted people Angle-closure glaucoma. A disease caused by a increased pressure in the eye (Green Star, med. also glaucoma called) and the for Blindness can lead!

Symptoms / complaints

The simplest sign of farsightedness is a blurred or blurred image Near lying objects. It often happens in young children Accompanying strabismus, due to the neural coupling of accommodation and convergence movement of the eye (fixing a point with both eyes). It comes to Inward squint, squint (Esotropy).

Further symptoms that can be caused by the constantly increasing focus are

Eye pain
a headache
Burning eyes
Conjunctivitis

blurred vision and easy fatigue (asthenopic symptoms or asthenopia).

Diagnosis of farsightedness

The diagnosis of Farsightedness can be determined by a refraction (refractive power determination) by the Ophthalmologist (Specialist for Ophthalmology) or optician put.

Excursus: Go to the ophthalmologist (specialist in ophthalmology) or to the optician?

Many patients who have farsightedness problems wonder whether they should see an ophthalmologist or an optician. The ophthalmologist is seen as a real specialist in eye diseases and the optician as a specialist in Glasses and contact lenses. Therefore the question is not that easy to answer.

In general, it can be said that both the ophthalmologist and the optician address the problem of Visual acuity identify. This does not mean that one can do better than the other. It depends a lot more on the experience of the individual. For this reason, one can say, provided one knows for sure, that the problem with visual acuity is real just to a single Farsightedness, myopia or Astigmatism / astigmatism it does not matter whether the correction calculation is carried out by an ophthalmologist (specialist in ophthalmology) or an optician.

With opticians, the diagnosis of farsightedness has the advantage that you can have the appropriate glasses or contact lenses made immediately. However, this should not be a reason to bypass the ophthalmologist's annual eye function check. Finally, it should not be forgotten that there are other causes of problems with farsightedness.
So you can use the symptom "Visual acuity problem“Treat easily, but to clarify other causes, it is better to see an ophthalmologist.
This applies to children (especially those who are noticing blurring for the first time) and for people who are also familiar with other clinical pictures (e.g. Diabetes mellitus, high blood pressure, etc.) and also people who have problems with their visual acuity despite their glasses / contact lenses.

Therapy farsightedness

There are now several therapy options for correcting farsightedness.

The oldest solution is that Glasses.
Later were then contact lenses developed. Basically, contact lenses are small, elastic glasses that are placed on the cornea. The advantage is that you do not immediately see that you are wearing glasses (cosmetic effect) and you do not need any annoying and sometimes also dangerous glasses. The disadvantage is that both eyes and contact lenses have to be cared for in a special way in order to maintain the functionality of the contact lenses and to avoid injuries to the cornea.

In principle, these are convex lenses (also plus lenses or converging lenses) that support the refractive power of the eye. This means that that part of the refractive power that the eye lacks is replaced by the converging lens. Nowadays technology is so advanced that it is very easy to control the power of the Eye to calculate.

However, sensitivity and experience are also required when determining the power for the required lenses, since one cannot correct the total farsightedness (because of the accommodation spasm, see above), but the manifest part and the latent part as far as possible.

In general, it can therefore be said that the strongest convex lenses can be prescribed for which the sharpness in the distance is just the best.

It is now also possible to have farsightedness with one Laser therapy to treat. The laser is used to do this Cornea soweit edited that the refractive power ratio is again in equilibrium with the axial ratio of the eyeball. This type of therapy is simple and effective in most cases. Nevertheless, various risks such as corneal scars, over- and under-correction and even deterioration in visual acuity have to be considered.

forecast

Since farsightedness rarely gets worse on its own and can be treated well with the help of corrective lenses, the prognosis is quite good. Presbyopia increases with age, but this can also be treated with the appropriate corrective lenses.