We have all heard of Lasik. It is a laser refractive surgery and what this procedure does is that it gets rid of glasses or contact lenses that a person is wearing. People refer to Lasik as laser eye surgery. The laser used for this procedure is known as the excimer laser. There are a few other lasers used in ophthalmology too.
LASIK does not change the condition of the eye except getting rid of the glasses or contact lenses. So let's say someone wears -5 numbered glasses but cannot see very clearly because of some retinal problem. After Lasik, wearing the -5 glasses won't be needed anymore. However, his vision will be the same as the -5 glasses, mainly because LASIK has not corrected the retinal problem.
When someone has eye power, they have to wear glasses or contact lenses to see things. What these visual aids do is focus the rays of light onto the retina because the shape of the eye does not do it properly for that particular individual.
Your eye doctor or refractive surgeon reshapes the cornea in a Lasik surgical procedure. After the laser, the eye can now focus light rays on the retina and see clearly. While reshaping the cornea, we remove micro-thin layers of the cornea. We remove around 10-12 microns of the cornea for every one diopter ( Unit of measurement of eye power) of power. So if you have a -5.00 eyesight power, then 5 X 10 microns = 50 microns of the cornea is removed. 1000 Microns make an mm.
This laser is wavefront-guided Lasik. What this means in simple terms is that we customize every Lasik to the individual. Thus even the natural and normal aberrations that every eye may have can be corrected with this procedure. In theory, even someone with normal vision can undergo LASIK because it would make the visual outcomes better than what vision was before.
You may wonder if removing a part of the cornea is safe. Well, to an extent, it is safe. However, removing more of the cornea while doing Lasik would not be safe if the cornea is already thin, which is why measuring the corneal thickness before this refractive surgery is essential. Pachymetry is the test used to measure corneal thickness.
The cornea is the front-most layer of the eye. It is transparent and is the first layer that light entering the eye hits. Corneal tissues are avascular, which means they don't have a blood supply. The cornea not having a blood supply may sound crazy, but thank god for that because the cornea is transparent, and we can see.
There are a few types of Lasik, but all of them do the same thing: change the cornea's shape.
Eye Solutions offers four types of Lasik refractive procedures. These variations occur because of changing technology.
Let us try and break it down for you as simply as we can.
Type 1 laser
The first type is one in which a corneal flap is created. This hinged flap is then lifted from the cornea, and the bed of the cornea is treated with the excimer laser. Now this hinged flap creation can be done in 2 ways.
By using a blade - Type A
Using laser is called a femtosecond laser and is the latest technology laser used in ophthalmology. - Type B
Once this laser treatment is over ( which takes a few seconds per eye ), the flap of the cornea is placed back in its position. After your eye doctor makes sure that the flap is correctly placed, a contact lens is placed on the eye. You can then go home.
Type 2 laser
In the second type, no flap is created in the cornea. We scrape off the epithelial layer of the cornea. The epithelium is the front-most layer of the cornea. Once this is scraped off, the remaining cornea is treated with a laser. After the treatment, a contact lens is placed on the eye.
The difference between the first and second types of LASIK
Type 3 laser
The third type of Lasik is called the" SMILE" procedure. Zeiss makes this laser technology. This is the video of how a smile procedure is done. As you will see here, too, there is no flap created. The laser used for this is also a femtosecond laser. This laser cuts out a spindle-shaped structure within the thickness of the cornea. Now that this spindle-shaped structure is cut, it needs to be removed. So a tiny 2mm opening is made on the cornea to reach that spindle shape and is pulled out. It will be easier to appreciate how a part of the cornea is removed here. The cornea thus becomes thinner than before the laser surgical procedure.
Usually, this laser for number removal is done after 19 or 20 years. The idea is that we want the number to stabilize and only then perform the laser. But it would be best if you remembered that this refractive procedure is elective.
There are a few reasons when someone cannot undergo Lasik
On the day of your surgical procedure, you should arrive at the clinic 30 minutes before the allotted time. At Eye Solutions, we reexamine the patient and repeat all the measurements. You must remember to take a head bath on that day and not use any eye makeup or perfume.
When you come to the hospital on the day of surgery, the registration formalities are completed, and you are directed to your room. Here you change into the hospital clothes and await your turn.
Once you enter the laser room, you will be made to lie down on the laser machine bed. The eye is cleaned with betadine, and a plastic drape or sheet is placed over your eye. A clip called a speculum is inserted in your eye to keep your eye open.
Depending on the laser ablation you are undergoing, a flap is created with a blade or the laser.
If you had chosen the femtosecond laser, you are moved to another laser machine, whereas if you had chosen the blade, you remain on the same laser machine.
Patients ask us, "what would happen if I move my eyes ?". This is a valid question, but you must remember that the procedure is concise, and the machines can detect the slightest eye movements. If a significant eye movement is detected, the laser immediately stops firing and waits for the eye to return to normal.
After the LASIK procedure, patients experience irritation and watering. Some even feel glare when they step out in bright lights and blurry vision, which is because there is a fresh wound on the cornea, and till it heals, these symptoms will persist. However, these symptoms don't last for more than a few days after surgery.
Your eye surgeon would prescribe a few eye drops. These eye drops have to be used for two weeks to 6 months. These drops help in healing and also help in preventing infections. Following are the prescription drugs.
Fluorometholone eye drop - Mild steroid - reduce corneal inflammation and help in healing.
Antibiotic steroid combination eye drops reduce corneal inflammation and help heal and reduce the risk of infection.
Lubricants or artificial tears - These drops reduce the symptoms of irritation that occur after Lasik. They also help in healing and reducing dry eye symptoms. In the initial days, patients may experience clearer vision every time they put on these artificial tears.
Usually, in a few days, patients become comfortable and can carry on their routine activities. Of course, because the myopic or minus eye power has become zero, the patient immediately notices that the distance vision has become clearer without glasses. We advise patients not to take a head bath for a few days and not swim for a month after the Lasik procedure. The healing process of the cornea can take a few weeks. For the vast majority, visual recovery happens much earlier.
There is always a tiny chance that a small eye number comes back after performing LASIK. The whole number treated does not come back, but a small number may, which is one of the potential risks of undergoing Lasik. We would not call it a surgical complication.
Also, one must remember that we will get reading glasses at 42. Of course, one may get these reading glasses a few years earlier or later. Lasik does not prevent that from happening. Once someone undergoes LASIK, at 42 years of age, they will have a challenge reading small print and wearing glasses.
Dryness is a known side effect of Lasik, which occurs because the laser damages some corneal nerves. All our patients who undergo Lasik in Mumbai are put on lubricants for 4-6 months after the procedure for this reason.
Lasik is mainly used as refractive surgery, getting rid of glasses. However, as mentioned earlier, this laser basically shaves off some part of the cornea and thus is used for some other condition as well.
Lasik is a very safe procedure, and we don't really see many complications
However, nothing is 100% in medicine. The complication that we are most worried about is an eye infection. Your doctor can treat these eye infections with eye drops. Very very rarely these result in significant loss of vision
We have to remember to go to a centre which has a clean environment. The LASIK machine is in a cleanroom because one of the complications of the LASIK procedure is a corneal infection, which we want to avoid.
Usually, LASIK surgery takes about 10 minutes in total. The procedure itself will take around 2 minutes for both eyes.
Most likely, you will see clearly by the same evening of the procedure. By the next day, you would resume regular activity but use drops and follow the doctor's protocols.
Insurance companies consider Lasik a cosmetic procedure and thus don't cover this procedure. Most of our patients are denied insurance. We rarely hear that some of our patients have been able to get their reimbursements.
HI