Learn why so many high school students wear glasses, the discomfort of lenses, the principles and differences between LASIK and LASIK, how each surgery affects nearsightedness and farsightedness, and the nature of vision recovery after surgery.
In today’s high schools, more than 80% of the class wears glasses. It’s not uncommon for students to start wearing glasses as early as elementary school or kindergarten. I myself went to the eye doctor when I was 7 years old, and was given glasses by the doctor who said, “Why did you wait until now? However, many students choose to wear contacts because of the discomfort of glasses and their interest in aesthetics. However, lenses are also a hassle to clean every day, and if you wear them for a long time, your eyes get tired easily. This is why surgeries such as LASIK and LASEK were introduced, and the number of people undergoing them is increasing. But how do these surgeries work and what are the differences between them?
Before we explain how these surgeries work, let”s first understand what myopia and hyperopia are. In order for us to see something, light must pass through the cornea and lens and focus precisely on the retina. However, in people with myopia, the conjunctiva is located a little further forward than the retina. This makes it difficult to see clearly, so glasses or lenses are worn to help the image land on the retina. The reason the image is in the front is because the cornea and lens are thicker, so concave lenses are used to weaken the light gathering so that the image is in the back of the focus. On the other hand, if you’re farsighted, the bifocals will be further back than the retina. In this case, convex lenses are used to gather more light and bring the focus to the front.
On the other hand, unlike glasses or lenses, LASIK and LASIK use a laser to reshape the cornea to achieve the same effect as lenses. First, let’s take a look at how LASIK works if you’re nearsighted. The cornea is made up of the corneal epithelium, which is the outer part of the cornea, and the corneal stroma, which is the parenchyma underneath. In LASIK, the surgeon starts by creating a corneal flap, which is a flap that contains the epithelium and some of the stroma. There are two types of flaps depending on how they are created: microkeratome flaps, which are created with a steel knife, and intrastromal flaps, which are created with a femtosecond laser. Once the flap is cut and the corneal parenchyma is exposed, the laser is applied to the center of the flap to thin the corneal parenchyma. The flap is then covered again so that the cornea is flatter after surgery. This will move light away from where it gathers to where the retina is, allowing you to see things normally. For hyperopia, the basic procedure is the same as for myopia, except that the corneal stroma is cut from the periphery rather than the center. However, vision recovery may be slower than with myopia.
In comparison, LASIK uses advanced technology to remove only the epithelium of the cornea. Then, a laser is used to thin the corneal stroma. The corneal epithelium is then thinned out with a laser, and the flap is not put back on like LASIK. Like LASIK, LASEK thins the center of the corneal stroma for nearsightedness and the periphery for farsightedness.
As mentioned above, the main difference between LASIK and LASEK is whether the corneal flap is made before the stroma is removed or whether only the epithelium is removed. Therefore, people with relatively thin corneas who cannot have a flap are recommended for LASIK rather than LASIK. Also, there is more of the corneal stroma left after LASIK than after LASIK. However, LASIK requires a longer recovery period and is more painful than LASIK because you have to wait for the corneal epithelium to heal. In terms of vision maintenance, LASIK is more stable after surgery, while LASIK tends to deteriorate over time.
Of the five senses, vision is arguably the most important. Poor vision can be a major inconvenience in daily life, so people have been trying to correct it. In this article, we’ll explain the principles and differences between two of the most recent techniques: LASIK and LASEK. LASIK and LASIK have different surgical methods and different effects, and each person’s eye structure is different, so it is important to visit an ophthalmologist and have an examination so that you can carefully decide whether LASIK or LASIK is right for you.
