2023-11-30 21:00:00
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Cloudy vision, sensitivity to light, discolored appreciation of colors or double visibility in one of the eyes are some of the symptoms that characterize appearance of cataracts. Yes, we are talking about that darkening of the lens of the eye that is so common in people with certain medical conditions or, usually, advanced age.
This is an alteration that normally appears very gradually and does not produce a sudden loss of vision. Now, if the disease is not addressed, it can end up being a inconvenient when carrying out the most mundane day-to-day tasks, such as reading, driving or even differentiating facial features in the people around you.
WHY ARE THEY PRODUCED?
Yes. We all know that a cataract is a darkening of the eye, almost as if it were a lens that fogs up and that loses transparency. Now, why does it happen and what exactly does it depend on? Well, most cataracts appear when the tissue that makes up the lens of the eye changes due to aging or some injuries.
The lens is made up of a series of proteins called crystal clear, which are organized among themselves to give rise to elongated fiber-shaped structures. They are characterized by being soluble in water, a property that gives the lens its peculiar transparency. However, over the years or, prematurely, after some type of injury, these proteins can break down and lose their fibrous appearance. That’s when they come togethereliminating the flexibility of the lens, making it denser and, consequently, causing vision to become opaque and cloudy.
National Eye Institute
Diagram of the parts of the eyeball.
And it is precisely the crystalline lens that is responsible for focus lights and images on the retina, just as if it were a lens. It is located just behind the iris, that is, the colored part, allowing light to pass through it as if it were a film from a camera. And, although it may seem almost a coincidence, it is normal for a person who develops a cataract in one eye to do so later also in the other. In fact, it is normal for them to occur at different rates: one eye may present a cataract that almost deprives vision while in the other only a small haze.
HOW ARE THEY TREATED?
Fortunately, although it is a very common condition, the treatments to eliminate them are generally safe and successful In its great majority. The most commonly used therapies include all surgeries, although different surgical techniques are available. Among them stands out the phacoemulsificationwhich involves using ultrasound to break down the cataract into small fragments that are then aspirated, and extracapsular surgery, in which the entire cataract is removed in one piece, leaving the lens capsule intact. In some cases, these procedures can be combined with laser therapy, which can facilitate the opening of the lens or the prior fragmentation of the cataract.
Additionally, after cataract removal in surgery, it is necessary to place a intraocular lens that replaces the natural lens of the eye, that is, it replaces the crystalline lens in its role of focusing light on the retina. There are different types of lenses that can do this job perfectly and the placement of one or the other will depend on the patient’s condition. They may be monofocal, multifocal or even toric lenses, which, in addition to helping vision, can help correct presbyopia and astigmatism.
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