How Does Laser Surgery for Eyes Work?

The Eye Laser Procedure Explained

The fundamental principle behind laser eye surgery involves reshaping the cornea to correct refractive errors. During the procedure, the surgeon first creates a thin flap in the cornea’s outer layer. This can be done using either a microkeratome (a precise surgical blade) or a femtosecond laser. Once the flap is created, it’s folded back to expose the middle section of the cornea called the stroma.

An excimer laser—which produces ultraviolet light—is then used to remove microscopic amounts of tissue from the stroma. This laser operates with remarkable precision, removing tissue in increments as small as 0.25 microns (1/4000th of a millimeter). For nearsightedness, the laser flattens the cornea; for farsightedness, it creates a steeper cornea; and for astigmatism, it smooths an irregular cornea into a more regular shape. After the reshaping is complete, the surgeon repositions the flap, which adheres naturally without stitches.

The entire procedure typically takes less than 30 minutes for both eyes, with the laser portion lasting only about 30-60 seconds per eye. Most patients experience improved vision immediately, with results continuing to improve over several days.

How to Prepare for Surgery

Proper preparation is crucial for a successful laser eye surgery experience. Initially, you’ll need a comprehensive eye examination to determine if you’re a suitable candidate. This evaluation includes measuring corneal thickness, pupil size, refractive error, corneal mapping, and assessing overall eye health. Your doctor will also review your medical history to identify any conditions that might affect surgery outcomes.

If you wear contact lenses, you’ll need to stop wearing them before the evaluation and surgery—typically 2-4 weeks for soft contacts and 4-6 weeks for rigid gas permeable lenses. This allows your cornea to return to its natural shape, ensuring accurate measurements and better surgical outcomes.

In the days leading up to surgery, you might be prescribed antibiotic eye drops to prevent infection. On surgery day, avoid wearing eye makeup, lotions, or perfumes, as these can increase infection risk. Arrange for someone to drive you home after the procedure, as your vision will be temporarily blurred and you may receive mild sedation.

Most surgeons recommend a light meal before arriving and comfortable clothing for the procedure. Following these preparation guidelines helps ensure optimal results and reduces complication risks.

Laser Surgery After Cataracts

While traditional cataract surgery involves replacing the cloudy natural lens with an artificial intraocular lens (IOL), laser technology has enhanced this procedure significantly. Laser-assisted cataract surgery uses femtosecond lasers to perform several critical steps that were previously done manually with surgical instruments.

The laser creates precise corneal incisions, performs the anterior capsulotomy (opening the lens capsule), and fragments the cataract for easier removal. This precision can lead to more predictable results and potentially faster healing times compared to conventional methods.

Following cataract removal, some patients may still experience residual refractive errors or develop posterior capsule opacification (PCO), sometimes called a “secondary cataract.” Laser procedures can address these issues. For residual refractive errors, LASIK or PRK might be performed to fine-tune vision. For PCO, a quick, painless YAG laser procedure creates a clear opening in the clouded capsule, restoring vision clarity without requiring additional lens surgery.

These post-cataract laser procedures typically occur several weeks to months after the initial cataract surgery, once the eye has fully healed and vision has stabilized.

Best Eye Laser Treatment Options

When considering laser eye surgery, several options exist, each with particular advantages for specific vision conditions:

LASIK remains the most popular choice, offering quick recovery and minimal discomfort. It’s suitable for treating nearsightedness, farsightedness, and astigmatism. PRK (Photorefractive Keratectomy) doesn’t create a corneal flap, making it safer for those with thinner corneas or active lifestyles with higher risk of eye injuries.

For those over 40 experiencing presbyopia (difficulty focusing on near objects), LASIK with monovision or SMILE (Small Incision Lenticule Extraction) offers solutions. SMILE uses a femtosecond laser to create a small lenticule (disc of tissue) within the cornea, which is then removed through a tiny incision. This newer procedure leaves more of the corneal surface intact, potentially reducing dry eye symptoms.

Custom or wavefront-guided procedures map the unique imperfections in each eye’s optical system, allowing for more personalized treatment. These advanced options may provide better night vision and contrast sensitivity compared to conventional procedures.

The “best” treatment depends on individual factors including corneal thickness, pupil size, degree of refractive error, lifestyle needs, and overall eye health. A comprehensive consultation with an experienced ophthalmologist is essential for determining the most appropriate option for your specific vision needs.

Contact Lenses vs. Laser Eye Surgery

Many people considering laser eye surgery are long-term contact lens wearers seeking a more permanent solution. While both options correct vision, they differ significantly in approach and outcomes.

Contact lenses provide temporary vision correction that must be inserted, removed, cleaned, and replaced regularly. They offer flexibility to change prescriptions as needed and can correct complex vision problems. However, they come with ongoing maintenance requirements, potential for infections, and recurring expenses for replacement lenses and solutions.

Laser eye surgery, conversely, offers a more permanent solution with a one-time procedure. Most patients achieve 20/20 vision or better without corrective lenses, eliminating the daily hassle and expense of contacts. The procedure typically pays for itself over time when compared to the lifetime cost of glasses or contacts.

However, not everyone qualifies for laser surgery. Conditions like severe dry eye, thin corneas, autoimmune disorders, or certain corneal diseases may disqualify candidates. Additionally, some patients may still need reading glasses as they age due to presbyopia, even after successful laser surgery.

For those considering transitioning from contacts to laser surgery, it’s important to follow your surgeon’s guidelines on discontinuing lens wear before evaluation and surgery to ensure accurate measurements and optimal outcomes.

This article is for informational purposes only and should not be considered medical advice. Please consult a qualified healthcare professional for personalized guidance and treatment.