Astigmatism Examination and treatment at DOmed
Astigmatism is the result of irregular curvature of the surface of the cornea. This means that those affected see both distant and close objects out of focus.
How does astigmatism occur?
Ideally, the curvature of the cornea should be even, like that of a sphere. This means that both vertical and horizontal lines can be portrayed sharply. If the cornea has a different curvature at different points, its shape is more like that of an egg than like that of a sphere. These differing curvature lines mean for example that light is refracted differently horizontally than vertically. The light is not focused at a single point but is portrayed as beams on the retina. The result is a distorted image and therefore distorted perception. For example, instead of a dot, those affected see a line; thus “astigmatism” (a- = without, stigma = mark or spot).
Astigmatism is mostly congenital and can also be passed on by parents to their children. Illnesses or scars which alter the cornea can also be the cause in some cases.
Symptoms of astigmatism
Those affected by astigmatism see both distant and close objects out of focus, blurry or distorted. This means that the act of seeing is extremely strenuous and patients suffer from eye pain, headaches and often burning eyes. In the case of children, the condition can lead to a decline in eyesight over time.
How can astigmatism be treated?
Astigmatism can be corrected with glasses or contact lenses. Optical compensation is achieved by compensating for the irregular curvature such that rays of light meet at a single focus point. In the case of glasses, this is achieved using so-called cylindrical glass, which must be positioned in a certain orientation in front of the eyes. Alternatively, astigmatism can also be treated with an operation. Femto LASIK is recommended in mild to medium cases of astigmatism. In severe cases of astigmatism, intraocular contact lenses are used for correction.
In combination with presbyopia, astigmatism can be corrected by placing multifocal intraocular lenses.