What Vision Problems Does Lasik Treat?
Laser-assisted in situ keratomileusis (LASIK) is an immensely popular and powerful tool for correcting nearsightedness, farsightedness, and astigmatism. Nearsightedness (myopia) is the most common issue treated, in which the eye focuses light in front of the retina. Farsightedness (hyperopia) is the opposite problem, in which the eye focuses light behind the retina. Astigmatism is caused by uneven focusing of the light within the eye. All of these issues cause blurry vision, and can be corrected via LASIK.
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Lasik For Farsightedness
In patients with farsightedness (hyperopia), the cornea of the eye is too flat. Without the necessary curvature, incoming light is not bent enough to focus on the retina. This can be corrected by steepening the cornea through LASIK. During the LASIK procedure, tissue from the periphery of the cornea is removed, causing steepening. When done correctly, this adjustment refocuses the light on the retina.
Lasik For Monovision
Monovision is a technique in which one eye is adjusted for distance vision, while the other is adjusted for near vision. While this may sound nausea-inducing, the brain can adjust, effectively restoring full vision. This intervention is commonly used for patients with presbyopia, which is the inability to focus their lens. After the age of 50, most people will develop some degree of presbyopia, and so one must be aware of it before getting LASIK. This condition hampers the eye’s ability to see at different distance ranges, and so regular lasik might only allow for near or far vision. Monovison works around this, restoring vision at both ranges.
Lasik For Dry Eyes
LASIK does not correct dry eyes, and a lack of sufficient tear film may interrupt the healing process. This is because the cornea repairs itself by migrating new cells in from the corneal periphery. The movement of these new cells is aided by the tear film, and so inadequate lubrication could severely restrict the cornea’s ability to heal itself. Many surgeons will require a patient to get their dry eye under control before undergoing the procedure. Artificial tears and addressing the underlying cause of the dry eye are a must before LASIK.
Lasik For Nearsightedness
Nearsightedness, or myopia, is a condition characterised by incorrect focusing of the light within the eye. The cornea, which is the outer layer of the eye, is too steep, and so light focuses in front of the retina. LASIK works by removing tissue from the center of the cornea, flattening it. This flattening works to move the focal point of the eye backward to meet the retina. This correction can reduce or remove the blurriness, giving the patient renewed vision immediately. Full healing can take several days, but the end result is usually wildly successful.
Lasik For Presbyopia
Presbyopia is a condition characterised by inflexibility of the lens. The most common cause is aging, and the majority of people will have some form of presbyopia by age 50. This condition can cause nearsightedness, causing patients to wear reading glasses. The reduced flexibility of the lens can hamper LASIK’s ability to correct visual problems, and so monovision may be a better option for those with presbyopia. Monovision is where one eye is corrected for distance and the other eye is corrected for near vision. This removes the need for the lens to adjust, as the patient can just switch eyes. To practice what it can be like, ask your doctor for a monovision contact lens trial run.
Lasik For Myopia
Myopia is the same as nearsightedness. Myopia, is a condition characterised by incorrect focusing of the light within the eye. The cornea, which is the outer layer of the eye, is too steep, and so light focuses in front of the retina. LASIK works by removing tissue from the center of the cornea, flattening it. This flattening works to move the focal point of the eye backward to meet the retina. This correction can reduce or remove the blurriness, giving the patient renewed vision immediately. Full healing can take several days, but the end result is usually wildly successful.
Lasik For Keratoconus
Keratoconus is the progressive weakening of cornea tissue that can pose a challenge to LASIK. Since LASIK removes tissue, a patient with keratoconus could suffer severe side effects if the cornea isn’t strengthened before the procedure. This strengthening can be done via a different procedure, called cross-linking. Cross-linking reinforces the cornea and can stop the progression of keratoconus, making LASIK possible. The final safety assessment will be determined by looking at the cornea thickness, stability of prescription, and overall eye health. Refer to your doctor before getting refractive surgery with keratoconus.
Lasik For Cataracts
A cataract is when the lens of the eye becomes cloudy. Since LASIK only adjusts the shape of the cornea, LASIK will not fix cataracts. However, vision issues can be corrected at the same time as cataracts. When replacing the lens of the eye, the surgeon has the option to choose a lens that can correct myopia, hyperopia, and/or astigmatism. Speak with your surgeon about lens options for cataract surgery.
Lasik For Glaucoma
Glaucoma is a condition characterized by raised intraocular pressure that can damage the optic nerve. This increased pressure is associated with many conditions (diabetes, migraines, high blood pressure, myopia, hyperopia, etc), and so one should continually monitor their eye pressure if diagnosed. Glaucoma can make the eye particularly sensitive to changes in pressure, and so certain precautions must be taken during and after the LASIK procedure. During LASIK, the eye is slightly compressed in order to stabilize it, which can lead to a temporary increase in pressure. In addition, the post-surgical medication given may cause a reversible increase in pressure. For these reasons, the surgeon needs to be aware of glaucoma so they can decide if a different procedure may be safer.
Lasik For Lazy Eye
A lazy eye, or amblyopia, is an interesting eye condition, as it is actually caused by faulty wiring in the brain. Usually beginning in childhood, amblyopia causes the brain to prioritise vision out of one eye instead of through both. The neural tracks controlling the non-dominant eye then do not develop as then should. The condition is treated by catching it early and applying vision therapy to equalize vision in the eyes. In adults, LASIK and other refractive procedures are not recommended on the small chance that they decrease vision in the dominant eye. For children, glasses or contacts are a better option, as a child’s prescription continues to change.
Lasik for hyperopia
Hyperopia, or farsightedness, is a condition when the eye focuses light behind the retina. This is caused by the cornea being too flat, and lacking the refractive power to bend the light enough. This can be corrected through LASIK or PRK. Both of these procedures ablate, or remove, tissue from the periphery of the cornea to steepen it. This correction can improve or completely correct the blurriness from hyperopia.
What are the primary types of refractive error that Lasik treats?
Refractive errors are conditions that affect the eyes ability to focus light. They include myopia, hyperopia, and astigmatism. Myopia, or nearsightedness, is characterised by a cornea that is too steep, resulting in light being focused in front of the retina. Hyperopia, or farsightedness, is the opposite problem, in which the cornea is too flat and light is focused behind the retina. Astigmatism is caused by asymmetry in the cornea distorting the focal point of light within the eye. All of these conditions may be reduced or corrected by LASIK. The degree to which one has those conditions will affect the treatment outcome. Hyperopia, myopia, and astigmatism are all measured in diopters, with larger numbers corresponding to a more severe condition. LASIK can correct myopia up to -11 diopters, hyperopia up to 5 diopters, and astigmatism up to 5 diopters.
Can you get Lasik for Astigmatism?
Yes, depending on the degree, astigmatism can be reduced or fully corrected. For more severe cases of astigmatism, LASIK may still be possible, but come with increased risk of side effects. The risk will depend on your prescription and overall eye health, and so discuss with your surgeon.
Schedule An Appointment
LASIK is an immensely powerful procedure that can be used to reduce or correct myopia, hyperopia, and astigmatism. While its effectiveness and safety will depend on the severity, the majority of people will be eligible. For those with presbyopia, monovision might be the best option. In monovision, one eye is corrected for near vision and the other for distance. Other conditions are not treatable via LASIK, such as dry eye, keratoconus, amblyopia, cataracts, and glaucoma.
Move to next chapter
Before surgery, expect to have an evaluation conducted by your eye doctor to ensure that you are a suitable candidate for lasik eye surgery and achieve optimal results. Before the evaluation, if you wear contacts, you will need to remain out of your contact lenses and switch to your glasses for some time as contact lenses can alter your cornea’s shape.