Astigmatism

The cornea is a bulging disc-shaped membrane that allows light from outside to penetrate the ocular structure to project onto the retina. For the cornea to function properly, it must be completely transparent and have the proper curvature.

El Astigmatism occurs when the curvature of the cornea is not uniform, projecting light that enters the eye at different points and providing blurred vision at all distances.

There are three types of astigmatisms and they can all be corrected through a refractive surgery.

Astigmatism

The cornea is a bulging disc-shaped membrane that allows light from outside to penetrate the ocular structure to project onto the retina. For the cornea to function properly, it must be completely transparent and have the proper curvature.

El Astigmatism occurs when the curvature of the cornea is not uniform, projecting light that enters the eye at different points and providing blurred vision at all distances.

There are three types of astigmatisms and they can all be corrected through a refractive surgery.

What is astigmatism?

El astigmatism is a refractive defect It causes blurred vision and distortion of images at short and long distance. Astigmatism originates when the cornea does not have the same curvature in all its parts and therefore adopts a elliptical or oval shape. The irregular curvature of the cornea causes the light entering from outside is projected at different points of the retina, causing blurred vision or distorted

In most cases, astigmatism is an abnormality hereditary, that is, people are born with the defect and, as the years go by, the symptoms occur. Astigmatism is usually accompanied by other refractive problems like the myopia and the farsightedness.

farsightedness

Types of astigmatism

Astigmatism is classified according to the angle of their axes and according to the focal lines. Thus we have the following types of astigmatism:

Regular and irregular astigmatism

  • In the regular astigmatism, the two axes are located at right angles. This type of astigmatism is the most common and can be corrected using contact lenses or surgery.
  • In the irregular astigmatism, the two axes are not at right angles to each other. This type of astigmatism is usually caused by the keratoconus.
astigmatism

Simple and compound astigmatism

El simple astigmatism It is one in which one of the focal lines is placed on the retina and the other behind or in front of it. This type of astigmatism can be:

  • Simple myopic: one of the two axes is short-sighted, that is, focuses in front of the retina and the other focuses on the retina.
  • Simple hypermetropic: one of the two axes is hyperopic, that is, focuses behind the retina and the other focuses on the retina.
simple myopic astigmatism

Simple myopic astigmatism

simple hypermetropic astigmatism

Simple hyperopic astigmatism

El compound astigmatism It occurs when none of the focal lines rests on the retina and no axis is emmetropic, that is, without graduation. This astigmatism can be:

  • Myopic compound: when the two axes are myopicThat is, they focus in front of the retina.
  • Hypermetropic compound: when the two eyes are farsightedthat is, they focus behind the retina.
  • Mixed: when one axis is short-sighted and the other hyperopicThat is, one axis focuses in front of the retina and the other behind.
compound myopic astigmatism

Compound myopic astigmatism

compound hypermetropic astigmatism

Compound hypermetropic astigmatism

mixed astigmatism

Mixed astigmatism

Causes of astigmatism

The irregular curvature of the cornea can be determined by the person's genetics or hereditary factor, which considerably increases the probability of suffering astigmatism, for corneal lesions, traumatisms in the eye or as a consequence of eye surgeriesLike cornea transplant or a operation Cataracts

What are the symptoms?

The astigmatism symptoms may vary according to type of astigmatism, patient age and graduation.

El main symptom of this refractive defect is the distorted vision of images at all distances, and the higher the graduation, the more severe the distortion. In addition to blurred vision, patients with astigmatism usually have no more symptoms. People with a high graduation of this refractive defect usually perceive only small details at all distances, due to the effort that the eye makes to focus.

If astigmatism is accompanied by farsightedness, the patient can experience headache, visual fatigue, difficulty changing distant vision to near, itching y redness of the eye. Why does astigmatism have no symptoms? This is due to the accommodating power of the lens of the eye that attempts to attenuate the vision defect making changes and movements that allow you to better focus the images.

Treatment of astigmatism

Astigmatism is a defect that can be temporarily corrected by wearing glasses or contact lenses, especially indicated in those people with very high rankings o aversion to the operating room.

If we want definitively eliminate the use of glasses or contact lenses we make a astigmatism operation through refractive surgery

Patients with keratoconus they may consider the option of undergoing a symmetric mini radial keratotomyfor that avoid the cornea transplant and try both keratoconus and astigmatism that produces.

myopia and astigmatism

Astigmatism operation

There are various surgical options that allow us eliminate astigmatism permanently. Among the techniques to correct astigmatism we have the laser techniques (FemtoLasik, LASIK y PRK) or the toric intraocular lens implant.

Additionally, eye surgery to eliminate astigmatism allows us to simultaneously correct myopia, hyperopia and presbyopia in the same operation.

FemtoLasik

Eye laser surgery FemtoLasik, is the surgical technique for correct astigmatism most modern that exists today.

This technique is characterized by being a fully laser eye intervention to correct the astigmatimo. The main difference with Lasik is that the cut in the cornea (flap) has evolved and instead of being done by means of a blade (microkeratome) it is done with a femtosecond laser.

This advance in combining the two lasers makes the astigmatism intervention Safer y more predictable and we have greater control.

LASIK

La Lasik surgery is most commonly used technique to operate with laser refractive defects such as myopia, farsightedness and astigmatism. The operation consists in making a very small incision in the superficial tissue of the cornea, to then apply the excimer laser programmed by the medical specialist.

The excimer laser helps mold imperfections of the curvature of the cornea to correct astigmatism and any other defect. The hard procedure 10 minutesit's ambulatory and is done under the influence of anesthetic eye drops

PRK

La PRK surgery is carried out separating the corneal epithelium With a special alcoholic substance. Once the epithelium has separated, the doctor will apply the excimer laser, previously programmed, to correct the defects that cause the graduation. When this is over correct astigmatism, the surgeon puts the epithelium back in its place and put some contact lenses that the patient should wear to protect the operated eye.

Like Lasik surgery, the PRK operation for astigmatism is ambulatory, hard 15 minutes and is done under the influence of anesthesia applied in drops.

Toric intraocular lens

Another alternative to correct astigmatism is the implantation of an intraocular lens, a highly recommended option for patients who are not candidates for laser surgeries like FemtoLASIK, Lasik or PRK

The toric intraocular lenses are designed to treat astigmatism permanently, since they allow correcting the asymmetry of the eye and greatly improve vision from far and near.

These lenses are manufactured with a custom curvature, according to the characteristics of the patient's eye, and provide great visual clarity. The placement of these intraocular lenses for astigmatism must be performed very rigorously for proper implantation. 

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Astigmatism
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Astigmatism
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Discover what astigmatism is, what its causes are and how it is corrected. We have financing plans.
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