ABOUT THE CONDITIONS
THAT CONTRIBUTE IN VISION PROBLEMS
What is Astigmatism?
Astigmatism is a type of refractive error in which the eye does not focus light evenly on the retina. In most cases, it is related to the cornea being elliptical (rather than spherical) with asymmetrical curvatures.
This results in distorted or blurred vision at all distances. The incoming rays of light do not focus on one point on the retina, as in normal eyes, but merge into one line forward or backward from the retina.
What causes astigmatism? Main causes:
It is usually due to the different curvature of the two corneal meridians (axes of the cornea), i.e. of the front part of the eye, which instead of having a spherical shape, it has an oval shape (like an egg). If the focus of the two images lies in front of the retina, we are talking about myopic astigmatism, and if it lies behind, we are talking about hyperopic astigmatism.
But it can also be mixed. Astigmatism can be either smooth (when the two axes are perpendicular to each other), or irregular (when the two axes are not perpendicular). Various pathologies (such as keratoconus) may worsen the refractive error.
The diagnosis of astigmatism is made with:
- A simple measurement of the visual acuity of the person
- Corneal Topography (pentacam, topolyzer)
Astigmatism can be treated with:
- Vision glasses with cylindrical lenses
- Toric contact lenses
- Refractive surgery