We use below tools or tests to check color vision deficiency.
LASIK is a popular laser eye surgery known since the 90s. It means Laser Assisted In-situ Keratomileusis. LASIK can correct nearsightedness, farsightedness, and astigmatism using a special laser. It reshapes the cornea in order to change the focusing power.
With nearsightedness (myopia), farsightedness (hyperopia) or astigmatism, the environment usually appears blurred and out of focus.
In these forms of ametropia, the refractive power of the eye is not optimal. Objects cannot be clearly depicted on the retina.
LASIK changes the refractive power of the cornea to correct the blurred vision. In this way, the light that passes through the cornea can properly reach the retina located in the back of the eye.
As a result, clear vision is again possible without glasses or contact lenses.
With good vision, the images focus on the retina at the back of the eye. With visual impairments, images are concentrated elsewhere, resulting in blurred vision. The LASIK lasers change the cornea to the extent that light is focused on the retina as it should.
As with all other laser vision correction methods, visual acuity must remain stable for at least one year before the LASIK surgery. There should be no eye disease like cataracts for example.
Laser eye surgery can last from 15 to 30 minutes, depending on the type of surgery and the individual patient’s prescription.
LASIK surgery has 4 stages. Before the doctor starts using the laser, your eyes are first anesthetized with a local anesthetic so that you do not feel anything during the operation. Second, the surgeon cuts a thin layer from the cornea of the eye.
The doctor then flips it aside, just like the cover of a book. Then deeper layers of the cornea are then flattened for shortsighted patients or twisted, for farsighted patients using a laser beam.
The ray of ultraviolet light removes these microscopic amounts of tissue from the cornea so that it focuses the light more accurately on the retina. With astigmatism, the laser can return an irregular cornea to its normal shape.
After that the thin slice of cornea is being returned to its place. It will grow on its own again. However, the cornea loses its mechanical stability. This cannot be changed by modern methods.
In most cases the normal vision returns a few hours after the surgery. Over time, your eyes will constantly improve. So it is possible to return to work a few days after and follow your daily routine.However, for a certain period of time you have to carefully clean your eyes every day and avoid sports activities.
Many people complain of dry eyes and other types of discomfort after surgery. In addition, at night there are some glare effects, which can affect you greatly. You might also have disturbing light phenomena that will appear. These symptoms usually disappear within the first three months.
However, when the corrections exceed five diopters, the effects of glare and other light phenomena may last a little longer. In most cases, these problems are temporary and disappear completely within three to six months.
We can answer this question with a resounding yes. This is due to the extremely low risk of complications. A team of researchers from refractive surgery centers in the United States and Germany analyzed 97 LASIK studies published between 2008 and 2015. They have also evaluated 68,000 eye surgeries to come to this result. The assessment is consistently positive:
An operation can never be risk-free. The greater the visual defect, the more likely side effects will occur. In general, laser treatment is used in patients with low, moderate and high nearsightedness, with low farsightedness (up to +4 diopters) and with astigmatism.
However, keep in mind that high myopia is the so-called progressive impairment. In other words, the nearsightedness will return in a few years, even after successful laser surgery.
There are also other restrictions. You can’t have a surgery if the cornea of your eye is already thin. The reason is that after the surgery the cornea is thinned and cannot undergo a second operation.
The prospect of improving vision and removing glasses or contact lenses makes LASIK laser eye surgery very attractive to many people. However, the operation is not cheap.
Depending on how severe the visual impairment is, which surgeon you choose, and which technology he or she uses, the cost can grow up to $2,300 per eye. The price often includes the actual operation, care before and after the operation, as well as a subsequent procedure if there is a need of fine-tuning.
LASIK surgery is usually more expensive for people with extremely poor eyesight. This means that the worse your vision, the more expensive your treatment will be.
Another component of the cost is the type of technology that is being used. New technologies often cost more than older ones. Before deciding on the technology, be sure to ask for the price of the LASIK procedure so that you know exactly what to expect.
The price can also be influenced by the surgical skills of the doctor. Experienced surgeons who work in well-known practices and clinics tend to charge more as they bring a higher level of skill to the procedure.
Last but not least, you should know about another popular vision correction surgery, which is often compared to LASIK. Photorefractive keratectomy (PRK) was first performed in 1987 and is considered a precursor to LASIK. Just like LASIK, PRK is a form of refractive surgery to correct nearsightedness, farsightedness and astigmatism.
PRK also works by reshaping the cornea with an excimer laser so that the light that enters the eye is properly focused on the retina for clear vision. However, there are a few differences that we would like to point out to you.
The main difference between PRK and LASIK is the first step of the procedure. PRK is designed to correct vision defects by using an excimer laser to reshape the cornea without creating a cornea valve.
First, in PRK, the thin outer layer of the cornea, (the tissue) is pushed or removed mechanically. Unlike LASIK, which produces a complete corneal valve, PRK leaves a thin layer of corneal epithelium.
In the next step, the excimer laser erases the cornea of a certain thickness based on the values measured during the preliminary examination. The refractive power of the cornea changes in such a way that the incoming light rays focus on the retina correctly, creating a clear visual image.
Finally, the corneal epithelium is pushed back and covered with a therapeutic contact lens. The contact lens protects the epithelium during the first 3 to 5 days. This is until the surface hardens and is subsequently removed. However, it may take two to three months for the vision to stabilize.
We use below tools or tests to check color vision deficiency.
