We have all heard of myopia, hyperopia and astigmatism. The first two more or less everyone knows what they are: myopia is when we do not see well from a distance and hyperopia when we cannot do it up close. But what about astigmatism, what exactly is astigmatism? Is it when we don’t see well from a distance or when we don’t see well up close? Well, neither one thing nor the other and both at the same time… Yes, we know that sounds a bit strange, so let’s explain it more clearly.
What is astigmatism?
Astigmatism, along with myopia, hyperopia and also presbyopia, is part of what is known as refractive errors. Refractive defects are understood as those that affect our focus, our refraction. That is, they cause us to not be able to focus correctly. As we have already said, myopia prevents us from focusing well on distant images and hyperopia on close objects. Astigmatism, on the other hand, prevents simply focusing at any distance. It is a refractive defect that causes a distortion of what we see.
Most of the time, astigmatism occurs combined with myopia or hyperopia. It is very rare that it occurs in isolation. Fortunately, as we will see below, the way to treat both refractive errors is the same.
Why does astigmatism occur?
As ophthalmologists in Barcelona we are faced with many cases of patients who present this pathology. But let’s explain in more depth what causes astigmatism: In order for us to focus images correctly, they must be reflected exactly on our retina. In the case of myopia, we are faced with larger eyes than usual, so the focus of distant objects occurs in a plane located in front of the retina. With farsightedness, just the opposite occurs, as they are smaller eyes, when we try to focus on distant objects, the point of focus is located behind the plane of the retina. Both in one case and in the other, the consequence is an image out of focus because it is not exactly located on the retina.
The cause of astigmatism we have to go looking for it in the form of the cornea and the lens. We remember that the cornea and the lens are the two lenses with which we focus on objects. The cornea is the external lens with the greatest power, and the lens is located inside the eye, behind the iris and has the ability to change its shape, and therefore its power to be able to focus on objects. In order for the focus to be carried out correctly, the curvature of both lenses must be the same.
How does a person with astigmatism see?
A normal cornea, without astigmatism, has a rounded shape, like a ball to understand us. In contrast, an astigmatic eye has a cornea with a more elongated, egg-shaped shape. This means that the curvature of the cornea is not uniform, but instead presents different curvatures in its different planes. These variations in curvature cause there to be a difference from the curvature of the lens. It is for this reason that astigmatism is always related to a specific degree of the cornea, the degree to which the curve does not coincide with the curvature of the lens.
The consequence is that instead of a single focus point, several focus points appear on the retina and, therefore, a distorted image is generated, both near and far objects. The vision of a person with astigmatism is therefore blurred, without sharpness, distorted
Is it a serious disease?
Neither astigmatism, nor myopia, nor astigmatism can be considered a disease. It is simply refractive error. In the same way that some are born with larger or smaller noses or ears, others are born with more or less large eyes or with a more or less uniform curvature.
Why does astigmatism appear?
The first thing we want to do is dispel false myths such as that astigmatism can appear from watching too much television or any other screen, reading in dim light, etc. It is unknown exactly what causes astigmatism astigmatism develops.
The only factor that seems to really have more weight is the hereditary factor. On the other hand, it has been proven that suffering some type of eye injury can also induce the appearance of astigmatism.
How can I eliminate astigmatism permanently?
Currently there are three methods to correct astigmatism:
- GLASSES OR CONTACT LENSES: It is the most classic and usual way to solve astigmatism. Using glasses or contact lenses that correct the refractive error and compensate for the variation in the curvature of the cornea, it is possible to refocus correctly. The main drawback of this solution is that it creates a dependency on glasses or contact lenses.
- EXCIMER LASER (LASIK OR PRK): Another of the most common methods to correct, not only astigmatism but any refractive defect, is through the Excimer laser. There are two techniques, LASIK or PRK, which have a slight variation in terms of the procedure, which will depend solely and exclusively on medical criteria. It consists of reshaping the cornea by means of highly controlled laser microshots to give it the correct shape and, in this way, cause the plane of focus to be exactly on the retina. The intervention is performed in an operating room that the patient can access on foot, without the need for a stretcher, and dressed in street clothes. No type of hospital admission is necessary. The patient is administered a small amount of sublingual sedation and at the end can go home on their own without problems. The intervention usually lasts about 10 minutes per eye. The same day of the intervention, the patient may present a somewhat blurred vision, but from the next day the vision will be practically 100%. If you want to know more about this technique, we recommend that you read this post that we dedicate entirely to laser surgery.
- COLLAGEN LENS: The latest solution, and one of the most advanced, consists of placing a small collagen lens inside the eye to correct astigmatism, or any other associated refractive error. It is like placing a contact lens but instead of on the cornea, inside the eye. This lens will have exactly the right prescription to compensate for the patient’s refractive error. It is placed between the iris and the lens, without contact with either of them. The great advantage of this solution is that no ocular structure is being modified, so that if the lens had to be removed, the eye would remain totally intact. The intervention It is performed through a microincision through which the folded lens is inserted and little by little it unfolds inside the eye until it is placed in the correct position. In this case, it is an outpatient surgery where the patient does enter on a stretcher. Of course, at the end he can go perfectly home on his own feet. The surgical time does not usually exceed 10 minutes per eye and after the intervention the patient already has a more than acceptable vision.
Of these three solutions, only the last two permanently solve the refractive error and do not generate dependence on any external element such as glasses.
When should I go to the ophthalmologist if I do not see clearly?
Not seeing clearly or not being able to focus at all distances is a clear symptom that there is some type of refractive error, in the best of cases. It is advisable to go to the ophthalmologist whenever we do not see properly, firstly because there are always solutions to improve our vision and secondly, and even more importantly, because a decrease in visual quality can hide other types of more serious diseases that require a more forceful and immediate medical -or perhaps surgical- action.
There are diseases such as glaucoma that must be treated as soon as possible because a decrease in vision will almost certainly be permanent and irrecoverable. We explained this more extensively in another article in which we analyzed what glaucoma is and what its consequences are.
On the other hand, astigmatism, myopia and hyperopia are defects that appear at a fairly early age, so correct them in time It is very important to avoid, among other things, problems of school failure. In this article we already talked about what astigmatism is.
Where can I treat my astigmatism with more guarantees?
As they say “experience is a degree” and in this regard, our center has the most expert specialists to treat not only astigmatism but any other type of refractive error.
In addition, we have with the most precise and state-of-the-art diagnostic technology to offer our patients the best solution to their eye problem.
Our Castanera Clinic is a pioneer in any branch of ophthalmology: cataracts, glaucoma, refractive defects, retina and macula… We even carry out different types of facial treatments with all the aesthetic solutions at your fingertips: botox, carboxytherapy, hyaluronic acid and of course blepharoplasty or eyelid surgery and also the removal of cysts and warts…
So if you have any type of eye problem and want to treat it With the maximum guarantees we will be happy to assist you.
