LASIK, an acronym for Laser-Assisted In Situ Keratomileusis, is a refractive procedure that reshapes the cornea to correct nearsightedness, farsightedness and astigmatism. It is the most common type of refractive surgery. Using targeted laser-beam energy, the LASIK procedure reshapes the cornea so that light rays are focused more precisely on the retina, producing clear, sharp vision.
Candidates Eligible for LASIK
LASIK is considered a safe procedure, yet it is not ideal for everyone. A thorough medical evaluation of the patient's eyes must be performed to determine whether the LASIK procedure is appropriate. Good candidates for LASIK are patients who:
- Are older than 18
- Not pregnant or nursing
- In general good health
- Have had stable vision for at least 6 months
- Have healthy corneal tissue, thick enough for a flap
- Have refractive errors that fall within the treatable range
It is also important for patients to fully understand the details and risks of the procedure, and to maintain realistic expectations for the outcome.
Benefits of LASIK
One of the primary benefits of LASIK is that patients immediately experience improved vision after surgery. For many people, laser eye surgery can correct their vision sufficiently to permit them to perform all, or most, of their daily activities without eyeglasses or contact lenses. Approximately 90 percent of patients who have undergone LASIK achieve 20/20 to 20/40 vision as a result of the procedure.
LASIK has the advantage of being a short procedure that results in permanent vision improvement. Most patients who choose to undergo LASIK achieve clear vision without corrective lenses, while also benefiting from minimal downtime and only mild postoperative discomfort.
The LASIK Procedure
LASIK is performed on an outpatient basis using only numbing eye drops to reduce any potential discomfort. The entire surgery takes less than 5 minutes to perform, although patients can expect to spend a few hours at the doctor's office. If requested, patients can receive an oral sedative prior to surgery to reduce any anxieties about the procedure.
During the LASIK procedure, the patient lies down in a reclining chair as the doctor positions the laser precisely over the eye. A speculum is used to keep the eye open while the eye is cleaned and anesthetic eye drops are administered. A corneal flap is created with either a blade or a laser. The surgeon gently lifts the surface of the cornea aside, enabling the excimer laser to reshape the curvature of the cornea.
The excimer laser delivers customized pulses of light energy based on each patient's prescription. The measurements for customization are determined prior to surgery, with the precise positioning confirmed prior to the start of the procedure. The second eye is treated immediately after the first. Following the surgery, the patient is provided with a protective shield to protect the eyes from bright lights.
Risks of LASIK
Any surgical procedure carries some risks, and patients should be aware that changes to the cornea made during LASIK cannot be reversed. Nonetheless, LASIK is considered safe for most eligible patients. While rare, complications may occur after the procedure, including:
- Undercorrection or overcorrection of vision
- Dry eyes
- Flap complications
- Postsurgical infection
- Increased sensitivity to light
- Visual problems, such as halos or night glare
- Fluctuating vision
Only 1 percent of patients undergoing LASIK experience complications.
Recovery After the LASIK Procedure
After LASIK, patients rest in the ophthalmologist's office for a short time before having someone else escort them home. Medication may be prescribed to relieve any discomfort experienced during the first 24 to 48 hours after surgery, but most patients tolerate this procedure well. The doctor will likely recommend a few hours of rest after treatment. Most patients are able to return to work and other regular activities the very next day. Patients who have undergone LASIK are instructed to avoid strenuous activities for at least a week.
Typically, patients experience a significant improvement in their vision immediately after the procedure, but the full benefits of LASIK may not be apparent for several months. While patients can achieve clear vision from LASIK, this procedure does not prevent the development of presbyopia, the age-related vision changes that occur after the age of 40. Many patients will need reading glasses for this condition, but their distance vision will remain clear.