Key points
- SMILE is a newer laser procedure: the laser cuts a small disc of tissue inside the cornea, and the surgeon removes it through a small incision (AAO).
- PRK removes the cornea's outer layer before laser reshaping. Expect a bandage contact lens, eye pain for 2 to 3 days and slower healing than LASIK (AAO).
- Implantable lenses (phakic IOLs, sometimes called ICLs) are for prescriptions too high to correct safely with cornea-based surgery, and in the U.S. are approved only for nearsightedness (AAO).
- Refractive lens exchange replaces the eye's natural lens with an artificial one (AAO).
Why a surgeon might steer you away from LASIK
According to the AAO, LASIK requires a prescription that has not changed much in the past year, a refractive error LASIK can treat, corneas that are thick enough and healthy, good overall eye health and realistic expectations. The AAO adds that severe dry eye and a history of certain eye infections can rule LASIK out.
The FDA lists more reasons to pause: a prescription that changed in the past year, a disease or medication that may affect wound healing, and previous eye injuries or surgeries. If you have been told you are “not an ideal candidate,” the first question is simple: which of these applies to me, and what did my measurements show?
The alternatives below are not automatically better in those situations. Which one fits, if any, depends on measurements and an examination that only a surgeon can do. Use this page to learn the vocabulary and the questions to ask.
SMILE (small incision lenticule extraction)
The AAO describes SMILE as a newer type of laser refractive surgery. LASIK involves a hinged corneal flap; SMILE works through a small incision instead. The AAO outlines the procedure this way:
- The eye is numbed with drops.
- A suction ring flattens the cornea.
- The laser cuts a disc-shaped piece of tissue, called the lenticule, inside the cornea and makes a small incision.
- The surgeon removes the disc through that incision.
Candidates need a prescription that has not changed in the past year, healthy corneas and generally good eye health. Our sources do not describe SMILE recovery times, so ask your surgeon for a written recovery plan.
PRK (photorefractive keratectomy)
Like LASIK, PRK treats nearsightedness, farsightedness and astigmatism by reshaping the cornea with a laser. The difference is the first step: the outer layer of the cornea is removed with a special brush, blade, laser or alcohol solution before the laser treatment.
Recovery is where PRK differs most. The AAO describes:
- A bandage contact lens placed on the eye after surgery.
- Someone must drive you home.
- Eye pain for 2 to 3 days.
- No strenuous activity for up to a week.
- Sun exposure can cause corneal scarring after surgery.
- Healing may take longer than after LASIK, according to the AAO's recovery guidance.
The AAO adds that PRK complications can often be improved with glasses, contact lenses or more laser surgery.
ICL and other phakic intraocular lenses
Phakic intraocular lenses take a different approach: instead of reshaping the cornea, a lens is added. The FDA describes them as thin lenses permanently implanted in the eye to correct nearsightedness and reduce the need for glasses or contacts. The AAO says they are for people whose refractive errors are too high to correct safely with cornea-based surgery. They are sometimes called an implantable contact lens (ICL) and are placed in front of or behind the iris, in front of the eye's natural lens.
Those figures come from an AAO article dated Feb. 27, 2017, which reported that phakic lenses were found safe and effective after five years. The same article notes two limits worth knowing: the procedure is more invasive than laser surgery, and in the U.S. phakic lenses are approved only for nearsightedness.
The FDA links to Devices@FDA for a list of approved phakic lenses. Ask your surgeon for the exact lens model and look it up there. New approvals appear about five working days after the end of the month in which they were approved.
Refractive lens exchange
The AAO describes refractive lens exchange, also called clear lens extraction, as replacing the eye's natural lens with an artificial lens to improve vision. Our sources do not yet cover who it suits or how recovery compares, so treat it as a topic to raise with your surgeon rather than something to decide from a web page.
Side by side
| Procedure | What happens | Meant for, per AAO and FDA | Recovery notes |
|---|---|---|---|
| LASIK | A laser reshapes the cornea; the procedure involves a hinged corneal flap | Stable prescription, corneas thick enough and healthy | Most people return to work and drive the next day |
| SMILE | The laser cuts a lenticule inside the cornea; the surgeon removes it through a small incision | Prescription unchanged for a year, healthy corneas | Not described in our sources; ask your surgeon |
| PRK | The outer corneal layer is removed, then a laser reshapes the cornea | Nearsightedness, farsightedness and astigmatism | Bandage contact lens, eye pain for 2 to 3 days, slower healing than LASIK |
| Phakic IOL (ICL) | A thin lens is permanently implanted in front of the natural lens | Nearsightedness too high for safe cornea-based surgery | More invasive than laser surgery; ask your surgeon |
| Refractive lens exchange | The natural lens is replaced with an artificial lens | Not described in our sources | Not described in our sources |
Cost and coverage
The FDA states that most medical insurance will not pay for refractive surgery. We do not publish prices, because we have not found dated, verifiable San Francisco price data. When you compare quotes, use the checklist in our LASIK guide. Check what the price includes, whether it is per eye, which follow-up visits are covered and what happens if a second procedure is needed.
Where to ask in San Francisco
UCSF Ophthalmology lists refractive surgery and cornea care among its services, and its Mission Bay clinic at 490 Illinois St. offers cornea and external disease care. Kaiser runs a closed HMO system; its Vision Essentials department at 1635 Divisadero St. lists LASIK among its services, so members can ask Kaiser which alternatives it offers. Independent practices also offer refractive procedures, and we do not rank them.
Questions to bring to your consultation
- Why is LASIK not my best option, specifically? What did my measurements show?
- Which alternatives did you consider for my eyes, and why do you prefer this one?
- How often do you perform this procedure, and who will see me at follow-up visits?
- What will recovery look like for my work, my commute and the sports I play?
- If you recommend a lens implant, which model is it, and is it on the FDA's approved list?
- What happens if my result is not what we planned?
Frequently asked questions
Is SMILE the same as LASIK?
No. Both are laser procedures that change the cornea, but LASIK involves a hinged corneal flap, while in SMILE the laser cuts a small disc of tissue inside the cornea that the surgeon removes through a small incision, as described by the AAO.
Is PRK recovery harder than LASIK recovery?
The AAO says healing may take longer after PRK. It describes a bandage contact lens, eye pain for 2 to 3 days and no strenuous activity for up to a week, and someone must drive you home after surgery.
Can an ICL correct farsightedness?
According to a 2017 AAO article, phakic lenses are approved in the U.S. only for nearsightedness. Check Devices@FDA for current approvals and ask your surgeon about your situation.
Does insurance pay for SMILE, PRK or an ICL?
The FDA says most medical insurance will not pay for refractive surgery. Confirm with your plan and get a written quote from the practice.
Which option is best if my corneas are thin?
We cannot answer that for you, and no website should. The AAO says phakic lenses are meant for refractive errors too high to correct safely with cornea-based surgery. Ask your surgeon to explain which options your measurements allow, and why.
Sources
- LASIK — American Academy of Ophthalmology
- When is LASIK not for me? — U.S. Food and Drug Administration
- What are the risks and how can I find the right doctor for me? — U.S. Food and Drug Administration
- What is small incision lenticule extraction (SMILE)? — American Academy of Ophthalmology
- Photorefractive keratectomy (PRK) — American Academy of Ophthalmology
- Recovery after laser surgery (May 25, 2023) — American Academy of Ophthalmology
- Phakic intraocular lenses — U.S. Food and Drug Administration
- FDA-approved phakic lenses — U.S. Food and Drug Administration
- Refractive surgery: alternative procedures — American Academy of Ophthalmology
- Phakic intraocular lenses for nearsightedness (Feb. 27, 2017) — American Academy of Ophthalmology
- Ophthalmology residency program — UCSF Department of Ophthalmology
- Ophthalmology and Optometry, Mission Bay — UCSF Health