Picture this: It’s the dead of night. Only a sliver of moon is visible through the clouds, casting deep, motionless shadows across your house. Suddenly, the stillness is broken by a tinkling noise from downstairs. You awaken with a startle, eyes frantically blinking away the sleep. It sounds like an intruder! Trying to pull your legs out from under the covers, you rub at your eyes to clear them but your vision is so blurry you can hardly see your slippers on the floor. It’s so hard to see… not only because it’s dark but because you’re also myopic and you broke your glasses two weeks ago and your contact lenses are in the bathroom drawer but you don’t think you could see well enough to make it to the bathroom, especially when your slinky cat has a penchant for tripping unsuspecting humans. Meanwhile, the intruder has stolen all your fine china and the good cutlery you bring out when your in-laws come for dinner.
Wouldn’t it be nice to be able to see clearly without your glasses or contacts?
Although LASIK eye surgery won’t give you the night vision of an owl, there are certainly many situations where it would be great to not have to rely on optical aids like glasses and contact lenses to function. While the aforementioned scenario is unlikely to happen (hopefully), think about occasions like going to the beach, playing sport, camping, or even cooking over a steamy stovetop. Glasses can break or be misplaced, contact lenses can tear or become uncomfortable, and not to mention the ongoing costs of replacements. Could LASIK laser surgery be just the thing you need?
How Does LASIK Work?
LASIK stands for laser-assisted in situ keratomileusis. It’s only one method of refractive eye surgery, a type of procedure designed to surgically correct the eye’s refractive error. Refractive error includes short-sightedness (myopia), long-sightedness (hyperopia), and astigmatism. Other methods of refractive surgery include PRK (photorefractive keratectomy), epi-LASEK (laser-assisted subepithelial keratectomy), and RLE (refractive lens exchange).
First introduced about four decades ago, today LASIK is a popular refractive procedure with high success rates and a good safety profile. Like all laser-based refractive surgeries, LASIK is built on reshaping the cornea, which is the clear front surface of the eyeball. By modifying the shape of this surface, the path of light is redirected as it enters the eye so that it forms a clear point on the retina at the back of the eyeball. This results in sharp vision – without glasses or contacts!
Before your eye surgeon performs LASIK on you, you’ll first undergo a comprehensive eye test to confirm your suitability. This will involve checking your vision, your prescription, and assessing the overall health of your eyes. Your specialist will also need to take some specific measurements that the computer will use to guide the laser during your LASIK surgery.
Once you’re ready to undergo the LASIK procedure, your eyes will be prepared with an anesthetic. Eye surgeons don’t tend to use general anesthesia; instead, you’ll have topical eye drops to numb your cornea, which may be re-instilled during the procedure. The superficial layers of your cornea will then need to be moved to the side by creating a hinged flap of tissue that will later be returned to position. This corneal flap can be made either by using a handheld bladed instrument or a femtosecond laser. Moving aside these top layers of tissue allows another laser tool, an excimer laser, to reshape the deeper corneal tissues. The excimer laser achieves this by vaporizing precise sections of cornea as programmed by the computer, a technique known as photoablation. Once this is done, the corneal flap is replaced in its original position.
Your eye surgeon will then give you a list of post-operative instructions and a couple of prescription eye drop medications to help the eye heal smoothly. The day after surgery you’ll most likely be feeling pretty good about your vision but it can take a few weeks for things to fully stabilize.
How to Know if You’re Suitable for LASIK and LASIK is Suitable for You
Your eye surgeon will be looking at several eligibility criteria before putting you under the laser, so to speak. This is to ensure the likelihood of a successful outcome and to minimize your risk of a complication or adverse side effect.
You may be unsuitable for LASIK if:
- You have another eye condition that is limiting your vision, such as a retinal disease, corneal scarring, or cataracts. Undergoing LASIK will not restore any vision lost from these conditions and so may be not worth the costs
- Have a corneal condition that may be exacerbated by the LASIK procedure. This includes a corneal thinning disease called keratoconus or a corneal infection such as from herpes simplex
- Have severe or persistent dry eye. LASIK is known to potentially exacerbate dry eye due to the disruption to the corneal nerves during the procedure
- Your vision is unstable due to situations such as pregnancy, other hormonal changes, systemic illnesses, or medications. Undergoing LASIK during a period of fluctuating vision will cause inaccuracies with your vision measurements
- Your pupils are very large. If your pupils are quite large even in bright conditions, you may experience uncomfortable glare and optical aberrations after your surgery due to more light entering the eye through the edges of your reshaped corneas
- Your corneas are too thin. A minimum amount of corneal tissue is required to perform photoablation without putting the eye at risk
- Your prescription is outside the treatable range for LASIK. This is considered in conjunction with the amount of available corneal thickness; the higher the prescription, the more corneal tissue that needs to be vaporized. As a general guide, LASIK is able to correct up to about -11.00D of short-sightedness, +5.00D of long-sightedness, and -5.00D of astigmatism
- Your work or hobbies puts you at risk of a corneal flap-related complication after surgery. Activities which involve a risk of trauma, such as the armed forces or contact sports, may cause the flap to dislocate. Activities in dusty and dirty environments like construction sites carry a risk of debris getting caught under the corneal flap
If this list has you feeling discouraged and like you’ll never be able to catch that midnight cutlery thief, do not fear. As mentioned, there are several other refractive surgery techniques that may still be suitable for you.
If you’re interested in freeing your vision from glasses and contact lenses, speak to your optometrist or eye surgeon about your eligibility for laser vision correction.
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