Many people who wear contact lenses or eyeglasses often hear about the option of getting something called laser eye surgery, or LASIK (an acronym for Laser-Assisted In Situ Keratomileusis).
While some prefer to stick with glasses or contacts, others wonder whether LASIK may be a better, easier option for them. We’re going to discuss the facts about LASIK from a medical standpoint and explain the pros and cons of surgery.The eye is very similar to a camera. The cornea and lens work together like the lens system of a camera, the pupil is the aperture, and the retina is the film. Myopia, or near-sightedness, means the image is focused in front of the retina; hyperopia, or far-sightedness, means the image is focused behind the retina; and astigmatism means the image on the retina is distorted.
These conditions lead to blurry images requiring correction with lenses or glasses. In a LASIK operation, the surgeon will reshape the cornea using laser technologies to focus the image directly onto the retina. This produces a clear, sharp image. Ultimately, many people achieve 20/20 vision after the surgery.
Who can get LASIK?
In the United States, LASIK is FDA-approved for people aged 18 or older. It’s also recommended that eyeglass prescriptions be stable for at least two years before undergoing LASIK.
Older patients with a visually significant cataract, i.e. opacified lens, should not get LASIK. Why? Because their refractive errors can generally be corrected with cataract surgery.
Certain professions do not allow employees to have any kind of refractive correction. So, be sure to find out if your job or future job has any restrictions about vision correction.
Are there any reasons why I should not get LASIK?
LASIK uses laser energy to thin out the cornea and change its shape. Therefore, people with an abnormally-shaped cornea (such as cone-shaped cornea or very thin cornea) should not get LASIK. The shape of the cornea may be progressively distorted and become thinner after surgery, producing poor vision and predisposing the eye to increased risks of injury.
After LASIK, the thinner cornea will affect measurement of the pressure inside the eye, which is important for the management of glaucoma. You should talk to your doctor if you have glaucoma, are at risk for glaucoma or have family members with the disease.
Other conditions that can affect the result of LASIK surgery include severe dry eye, graft versus host disease, any ocular surface disorders, history of bacterial or herpetic corneal ulcer, autoimmune eye diseases, and refractive instability (the need to change glasses every year or so). If you have any of these conditions, talk to your doctor before committing to surgery.
How much refractive error can LASIK correct?
LASIK can achieve good results in people with low to moderate myopia less than -6.00 diopter (otherwise known as a measurement unit of your glasses), hyperopia up to +5.00 diopter, and astigmatism up to 2.00 diopter.1 Some LASIK centers have the ability to correct more severe conditions, but the after-surgery results aren’t always predictable.
Will I be satisfied after surgery?
According to the Joint LASIK Study Task Force, which surveyed patient satisfaction showed that in general, 95.4% of 2198 patients were satisfied after LASIK.2 In a different study, up to 97% of patients achieved 20/20 vision, as observed at a six-month follow-up.3
According to Joint LASIK Study Task Force, 95.4% were satisfied after LASIK.
As people grow older, they lose the ability to focus on nearby objects (typically in their 40s) and may need reading glasses. This is a natural process called presbyopia. If you have LASIK when you are young and achieved 20/20 vision, you may need reading glasses if you develop presbyopia in your 40s.
What are some complications of LASIK?
LASIK is a relatively new procedure. The first lasers were approved in the mid to late 1990s by the FDA (FDA approves medical devices and not the procedure itself). Therefore, long-term effects of laser eye surgery are still unknown and the FDA is currently studying patient reported outcomes; LASIK Quality of Life Collaboration Project.4
The two most common complications that patients experience after LASIK is under or overcorrection and dry eyes. With undercorrection or overcorrection, the problem is that the patient does not achieve 20/20 vision and may need postoperative enhancement or continued use of glasses. Some patients with dry eyes prior to LASIK report a significant decrease in their quality of life after the surgery. So, if you suffer from dry eyes, carefully consider LASIK before you decide to go for it.
Some patients develop something called high-order aberrations, where they experience increased glare, halo around lights at night, and/or loss of contrast sensitivity. Some of these higher order aberrations are less of a problem with LASIK using wavefront technology (discussed later).
Remember that LASIK is an elective procedure and consider the risks of surgery before making this decision.
Other postoperative complications that have been reported are: button-holed, folded or dislocated flap; infection of the cornea; erosion of the corneal epithelium or improper healing causing ingrowth of the epithelium into the wound; ectasia, i.e. progressive thinning and distortion of the cornea. A feared complication is retinal detachment that can result in permanent loss of vision. But chances of retinal detachment are very slim--0.06%, 24 months after the initial LASIK procedure in a series.5 However, patients with high myopia are predisposed to higher risks of retinal detachment in general because of the thin retina from the myopic degeneration.
As with any medical procedure, there are many known complications. Fortunately, most of them are rare and effect only a small number of patients. However, it is still important to learn and research these thoroughly before undergoing any procedure.
How much does LASIK cost?
In 2010, the average cost was $2,150 for all laser-based vision correction procedures, $1,580 for non-customized LASIK using mechanical microkeratome or not guided by wavefront analysis, and $2,170 for wavefront-guided LASIK with laser-created flap.6,7 Wavefront technology maps the higher-order aberrations in your eye, which, once again, can produce halos, starbursts or double vision after surgery. Not everyone needs wavefront analysis. Your doctor will determine this.
Cost for Lasik varies widely, ranging from $500 to $2200 per eye.
The FDA does not control the price of LASIK procedure. So if your price quote is in the upper range, ask your surgeon to justify the price. Why are you paying top dollar? Ask whether the surgeon using newer technology, exceptional credentials, service warranty, etc. If your quote is in the lower range, inquire if the surgeon is experienced, if the full price is being quoted or if there are any hidden costs.
How do I choose a surgeon?
Although financial consideration is important, you ought to consider the following factors when selecting your eye surgeon:
- Credentials - ensure that your eye surgeon is licensed and board certified.
- Reputation - search online forums, speak with prior patients, ask friends for referrals, or ask other patients in the room if they are happy with their surgeon.
- Experience - ask the doctor what his/her numbers are, e.g. cases performed, success rate, complication rate and how it compares to national averages, any outbreak of eye infections at their center, where the procedure is performed, patient satisfaction rate, etc.
- Technology - ask what technologies are being used. IntraLase flap creation costs more and some surgeons argue that it is safer and more consistent than mechanical creation using a bladed keratome. Custom LASIK using wavefront technology can detect and correct aberrations, but is a more expensive procedure.
- Postoperative care - ask how your doctor will provide care for you after surgery, especially if things go wrong, such as follow-up and costs of complications, or costs of enhancement.
- Intangibles - do you like and trust your surgeon?
How do I prepare for surgery?
Discuss your expectations and post-surgery plan with your surgeon.
Wearing contact lenses can warp the cornea, affecting its shape and thickness. Before LASIK, the shape and thickness of the cornea are measured and used to determine the surgical parameters, i.e. where and how much corneal tissue to remove.
It is best to stop wearing soft contact lenses at least one week before surgery and hard contact lenses at least six weeks prior.
Ask your eye surgeon any questions you may have. Important topics to discuss with your doctor are: history of eye infections or surgeries, systemic diseases such as diabetes or autoimmune diseases; if you are taking medications such as Imitrex, Acutane, or antihistamines; if you play contact sports; if you drink or smoke excessively. These factors can influence your recovery and, ultimately, your vision.
What should I expect on the day of surgery?
This is an ambulatory procedure, meaning you will go home the same day. You should be able to go to work the next day, unless you are a contact sport athlete. Patients are awake during the procedure with some mild oral sedation and topical anesthetics.
Once you are in the operating room, your eye surgeon will instill a topical anesthetic drop onto your cornea, place a speculum to hold the eyelids open, perform some markings, create and unfold a flap of corneal tissue either using a special blade (called a microkeratome) or IntraLase laser, remodel your cornea using laser energy, then reposition the flap.
Although all current laser systems are equipped with an eye tracking system to improve precision of laser energy placement, you should try to refrain from any movement as much as possible and maintain focus at the target light.
What should I expect after the surgery?
You will be given a course of antibiotic and anti-inflammatory eye drops.
Avoid rubbing your operated eye during the first few weeks to allow the tissue to heal.
It is important that you follow your doctor's instructions. If you have any questions about what to do and what not to do, ask your doctor immediately.
You may develop an area of redness, called subconjunctival hemorrhage, caused by the corneal suction ring placement, which is employed to immobilize the cornea during flap creation. This is normal and complete resolution that’s expected to occur within a week or two after the surgery. If you develop diffuse redness of the eye, haziness of the cornea, decreased vision, or pain, seek medical attention immediately.
Other important considerations
As discussed above, many people develop age-related cataracts and some require cataract surgery. This includes LASIK patients. Behind the cornea within your eye is the lens, which helps focus the light onto the retina. A cataract is a clouding of the lens--you can compare it to a dirty window. Cataract surgery involves removing the opaque or “cloudy” lens in your eye and replacing it with a prosthesis to improve visual clarity. Because LASIK changes the shape and thickness of your cornea, it may cause inaccurate calculations for a lens implant.
Any patient who plans to have LASIK should request preoperative measurements and store this record in a safe place, in case there is ever a need for cataract surgery in the future.
Currently, the measurement of intraocular pressure is also dependent on the thickness of the cornea. Measurements through a thinner post-LASIK cornea tend to underestimate the eye pressure, affecting management of glaucoma. So, if you or your family have glaucoma, you must have a discussion with your surgeon prior to LASIK. Again, it may be a good idea to request preoperative measurements and keep these records safe, so that your doctor is aware of your baseline measurements.
Our hope is that this article provides you with a great start to learning about LASIK and making an informed and educated decision. The FDA’s website also provides great information on this procedure and you can visit them here.
1 Sugar A, Rapuano CJ, Culbertson W, Huang D, Varley GA, Agapitos PJ, de Luise V, Koch DD. Laser in situ keratomileusis for myopia and astigmatism: safety and efficacy. Ophthalmology. 2002 Jan;109(1):175-187.
2 Solomon KD, Fernández de Castro LE, Sandoval HP, Biber JM, Groat B, Neff KD, Ying MS, French JW, Donnenfeld ED, Lindstrom RL; Joint LASIK Study Task Force. LASIK world literature review: quality of life and patient satisfaction. Ophthalmology. 2009 Apr;116(4):691-701.
3 Christenbury JD. All-laser LASIK proves worth - Large, single-center study provides visual results of 14,126 eyes with LASIK. Ophthalmology Times. 2012 Feb;37(3):26.
4 FDA website, cited on 2/25/12.
5 Arevalo JF, Ramirez E, Suarez E, Cortez RI, Antzoulatos G, Stopello JM, Ramirez R, Torres F, Gonzalez-Vivas R. Rhegmatogenous retinal detachment in myopic eyes after laser in situ keratomileusis: Frequency, characteristics, and mechanism. Journal of cataract and refractive surgery. 2001 May;27(5):674-680.
6 Segre L, Haddrill M, Epstein RL. Cost of LASIK Eye Surgery and Other Corrective Procedures. Website, page updated 10/13/11, cited on (cited on 1/8/2012)
7 Bethke W. LASIK Surgeons pine for patients. Ophthalmology Times. 2012 Feb;37(3):46.
8Varley GA, Huang D, Rapuano CJ, Schallhorn S, Wachler BS, Sugar A. LASIK for hyperopia, hyperopic astigmatism, and mixed astigmatism. Ophthalmology. 2004 Aug;111(8):1604-1617