Refractive Surgery Options

As you may know laser in situ keratomileusis (LASIK) procedures to eliminate or minimize myopia (nearsightedness), hyperopia (farsightedness), and astigmatism have been performed in the United States and throughout the world for many years now.  If you are dependent on your eyeglasses and/or contact lenses to see better, you may be a good candidate for LASIK.

Our associated surgeons at the SoCal Eye may recommend photorefractive keratectomy (PRK), small incision lenticule extraction (SMILE), or EVO implantable collamer lens (ICL) if you are not a good candidate for LASIK.

LASIK, PRK, and SMILE use a laser treatment to reshape the front part of the eye called cornea whereas EVO ICL uses intraocular lenses in order to help you see better without eyeglasses or contact lenses.

Differences Between LASIK, PRK, SMILE, and EVO ICL


LASIK is a flap surgery.  After the eye is anesthetized with drops, femtosecond laser pulses are used to create a flap within the front portion of the cornea.  The prepared flap is folded back to expose the inner corneal tissue to be treated.  An excimer laser is then used to sculpt the corneal tissue within a matter of seconds.  LASIK is commonly used for patients with sufficient corneal thickness, who have an average level of nearsightedness or farsightedness and any level of astigmatism.  It has the fastest visual recovery time.  Patients usually report excellent vision within 24 hours.  It can produce light sensitivity, scratchiness, tearing for 4-5 hours following the procedure.  The risk for dry eye can be noticeable up to 1 year.  The procedure is 95% in producing the accuracy and likelihood of achieving 20/20 vision.


PRK is a surface ablation surgery.  With the eye being anesthetized, a diluted alcohol solution is applied to loosen the outer layer of the cornea (skin cells).  The skin cells are then removed using a manual instrument.  Like LASIK, the procedure uses an excimer laser to reshape the cornea.  However, unlike LASIK, no flap is created.  The epithelial layer then grows back as the cornea heals after surgery.  PRK is recommended for patients whose corneal thickness is not suitable for either LASIK or SMILE.  However, patients can expect to have excellent vision, comparable to patients who have LASIK or SMILE.  A protective bandage contact lens will be placed during surgery and will need to be removed after 4 days.  The procedure has the longest visual recovery time compared to LASIK or SMILE and will take about 1 week to feel comfortable driving, particularly in unfamiliar areas.  It can produce intermittent light sensitivity, scratchiness, tearing for 4 days following the procedure.  The risk of dry eye can be noticeable up to 1 year.  The procedure is 95% in producing the accuracy and likelihood of achieving 20/20 vision.


SMILE is a minimally invasive surgery.  A contact-lens-shaped piece of corneal tissue called a lenticule is created inside the intact cornea using a femtosecond laser on an anesthetized eye.  The lenticule is then dissected and removed through the small tunnel incision with minimal disruption of the skin cells.  SMILE is recommended for patients with moderate to high nearsightedness but without astigmatism.  This laser refractive surgery option is great for patients with a high risk of developing dry eye.  It takes medium visual recovery time.  The procedure is minimally invasive, fast, and least discomfort after surgery.  However, it can produce light sensitivity, scratchiness, tearing for 1-2 hours following the procedure.  This treatment for refractive errors is 95% in producing the accuracy and likelihood of achieving 20/20 vision. 


EVO ICL is an alternative to LASIK and PRK.  An implantable collamar lens is inserted through a small incision on an anesthetized eye and is placed behind the iris, and in front of the natural crystalline lens.  Unlike LASIK, PRK, or SMILE, the procedure does not involve removing of corneal tissue making it potentially reversible.  It is usually a quick procedure (30 minutes).  Recovery time is relatively short.  Most patients experience improved vision within a few days.  The procedure is recommended for patients with thin corneas or certain corneal irregularities with moderate to high nearsightedness, farsightedness, and astigmatism who may not be eligible for LASIK or PRK.  The advantages of this procedure are: (1) in harmony with natural eyes, (2) no dry eye syndrome, (3) additive technology, and (4) excellent night vision.

To schedule a consultation with Dr. Eap to determine if you are a good candidate for one of the refractive surgery options, please contact us.