Near sight, long sight, astigmatism
What is farsightedness (hypermetropia)?
In case of farsightedness or hypermetropia, the beams are focused behind retina, the reasons for that can be weak refraction on the optical system, a short eye.
A farsighted man sees badly in close distance and in far distance.
There are three stages of hypermetropia:
·mild – until 2 dioptres;
·medium – from 2 to 5 dioptres;
·severe – more than 5 dioptres.
Mild stages of hypermetropia can be compensated by acommodation tension; i.e., excessive tension of muscle changing the form of the lens in order to increase its refractive power. It is called a masked hypermetropia.
Treatment of hypermetropia is correction by glasses, contact or surgical correction.
Following operations are performed in hypermetropia:
· Conductive keratoplasty – see the section “News”- “treatment news”- a new revolutionary technology for vision correction in farsightedness and presbiopia (aging farsightedness), is considered an ideal procedure.
·Thermokeratoplasty – refractive effect is achieved by applying coagulates on the corneal periphery by a metallic needle heated until a certain temperature, when it shrinks in the result, increasing refraction of the central optical zone.
·Laser coagulation – the essence of the operation is the same that in keratoplasty, with the difference that energy of laser irradiation is used instead of a heated needle.
·Hypermetropic LASIK – a rag is formed from the superficial corneal parts, it is taken back and periphery of the central optical zone is heated in a form of ring by an excimer laser. The cornea becomes more convex and its refractive power increases in the result.www.WaveLight.com
·Hypermetropic artiphakia – the essence of the operation – extirpation of the original lens and implantation of an artificial lens with a larger optical power.
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