Contactology deals with the adaptation of contact lenses. The main motivations of use are: aesthetics, to do sport, for their most natural vision and for their comfort.
First of all, the optometrist evaluates the graduation, the status of the binocular vision, as well as the health of the visual system, with special attention to the cornea, conjunctiva, eyelids and condition of the tear.
In the adaptation of the contact lenses, the curvature of the cornea is measured with the help of a keratometer or topographer, in order to determine the radius of the lenses and their size and that they adjust comfortably to the eye.
Topografia d´una còrnia normal
There are two large families of contact lens materials: soft and semi-rigid, but the most common adaptations are standard. These are usually soft, silicone hydrogel, with a very high oxygen flow because the eyes breathe, very comfortable and most often, frequent renewal (they are renewed every day or a month).
The special adaptations can be:
a- Orto-K: it is a technique in which contact lenses are carried by night. These make a temporary change in the curvature of the cornea. During the day, the person sees clear. This should be done as long as they want their effects to last, since when contact lenses are left, the refractive error returns.
b- Myopia control: in people whose myopia is increasing, it has been seen that they have a greater peripheral hyperopic blur. There are now reverse geometry contact lenses that correct it. The effect sought is to slow down this progression. The results of recent clinical studies show that this is the case.
c- Keratoconus: it is a slimming of the cornea, with increased curvature and myopia, which occurs especially in adolescents. The cornea becomes very irregular, it deforms and the normal contact lenses do not have a good stability. Many designs have been developed depending on the degree to which the patient is.
d- Post-lasik: there are people who, after the operation of myopia, this is returned. Since the laser has modified the curvature of the cornea, the normal contact lenses do not stabilize well.
e- Post-traumatic: Sometimes, after an accident, the cornea may be damaged. Normally, due to the scar, the cornea is irregular, with the consequent loss of clarity in the image. There are contact lenses that restore regularity and therefore, the sharpness of the vision
f- Filters: Color blinds can benefit from specific filters to improve color vision and dyslexics, increase their performance.
g- Special cosmetics: after a serious illness of the eye in which the vision has been lost, it can happen that the aesthetic effect is not pleasant. In these cases, there are lenses that simulate natural iris in order to restore the normal appearance.
Learning the manipulation of contact lenses is easy and does not require, in general, too much time. Yes it is important to be clean and to respect the recommendations of use.