Laser Eye Surgery Risks and Side Effects: What the Evidence Shows

Short answer: Laser eye surgery has a low rate of serious complications for people who are good candidates. The most common side effects are dry eyes and glare, halos or starbursts at night, which are usually temporary. Less common are flap problems after LASIK, haze after PRK, and a small leftover prescription that may need an enhancement. Serious complications are rare: infection follows about 1 in 22,000 LASIK procedures (Schallhorn et al., 2017), and corneal ectasia occurs in fewer than 1 in 1,000 LASIK eyes without risk factors (Moshirfar et al., 2021). In a review of 97 studies, 0.61% of LASIK eyes lost two or more lines of vision with glasses (Sandoval et al., 2016). Careful screening of your eyes before surgery is the most important way to lower your risk.

Watch: the risks of your procedure

Before your surgery, you watch the consent video for your procedure. It explains the risks and the important recovery information. This one is for LASIK and CLEAR:

And this one is for PRK:

Is laser eye surgery safe?

Most people are very pleased with the results, but like any operation, laser eye surgery has risks (FDA). The evidence for LASIK is large:

• In a review of 97 studies of modern LASIK, 0.61% of eyes lost two or more lines of vision with glasses (Sandoval et al., 2016).
• Across 19 studies and 2,198 patients, 95.4% were satisfied with their result (Solomon et al., 2009).

For TransPRK, a published series of 205 eyes treated at one Brisbane site found that no eye lost two or more lines of vision (Gunn & Cox, 2024). See our published TransPRK results.

Risks at a glance

Risk	How common	What it means
Dry eyes	Common, usually temporary	Gritty or fluctuating vision for weeks to months; treated with drops
Glare, halos, starbursts	Common early; rarely bothersome by 1 year	Rings or rays around lights, mainly at night
Leftover prescription	Uncommon	May need an enhancement, free for two years at Focus Vision
Inflammation under the flap (DLK)	6.3% of femtosecond LASIK eyes	Typically settles without lasting effect on vision
Cells growing under the flap	2.1% of femtosecond LASIK eyes	Monitored, and treated if it affects vision
Incomplete flap	0.17% of femtosecond LASIK eyes	The flap doesn’t form fully during surgery
Haze after PRK	Uncommon; lowered by mitomycin C	A faint scar that can blur vision
Infection	Rare: about 1 in 22,000 LASIK and 1 in 7,400 PRK procedures	Treated urgently with drops
Corneal ectasia	Rare: about 90 per 100,000 LASIK eyes without risk factors	Weakening and bulging of the cornea

Sources: dry eye and halos (Lobanoff et al., 2026); flap complications (Butt et al., 2026); haze (Chang et al., 2021); infection (Schallhorn et al., 2017); ectasia (Moshirfar et al., 2021).

Common side effects

Dry eyes

Dry eye is the most common side effect of laser eye surgery. The treatment affects the nerves in the cornea that help trigger tears, so vision can blur or fluctuate, even when the eye doesn’t feel dry. It usually settles over three to six months (AAO EyeWiki). A year after LASIK, 72% of people had no dry-eye symptoms, although 42% were still using artificial tears, mostly once a day (Lobanoff et al., 2026).

In the early months, dry eye is less common after SMILE-type lenticule extraction, the same family as CLEAR, than after femtosecond LASIK (Shen et al., 2016). Rarely, dry eye is severe or lasting (FDA), which is why existing dry eye is treated before surgery.

Glare, halos and starbursts

Rings or rays around lights, mainly at night, are common in the first weeks. A year after LASIK, only 1% to 3% of people found halos, glare or starbursts very bothersome, though night driving was the area where most people still noticed some difficulty (Lobanoff et al., 2026). See dry eye, glare and halos after LASIK for the full results.

A leftover prescription

Sometimes the eye heals slightly differently from the plan, leaving a small prescription; you may still need glasses for some tasks (FDA). At Focus Vision, an enhancement is free for two years after LASIK, Ray Tracing LASIK, TransPRK and CLEAR, when it is safe and worthwhile. See our enhancement policy.

Laser eye surgery also doesn’t stop the normal ageing of the eye. From your mid-40s, you’ll gradually need reading glasses, as everyone does. See laser for reading glasses.

Risks by procedure

LASIK

In LASIK, a femtosecond laser makes a thin flap, and an excimer laser reshapes the cornea underneath. The flap is what gives LASIK its fast recovery, and it is also the source of its specific risks. In a 2026 review of 27 studies and 28,531 femtosecond LASIK eyes (Butt et al., 2026):

• Inflammation under the flap (diffuse lamellar keratitis) was reported in 6.3% of eyes and typically resolved without long-term effect on vision.
• Surface cells growing under the flap (epithelial ingrowth) occurred in 2.1%.
• Fine wrinkles in the flap (microstriae) occurred in 1.6%.
• Incomplete flaps occurred in 0.17%, and other flap events, such as tears or injury to the flap, in fewer than 1%.

Injury to the flap from a knock to the eye was rare, in fewer than 1% of eyes. Even so, if you play contact sports or work where eye injury is likely, a flap-free procedure may suit you better. See who should not have laser eye surgery.

CLEAR

CLEAR is a femtosecond-only treatment: the laser shapes a thin disc of tissue inside the cornea, which is removed through a small incision, with no flap. Its outcomes are comparable to SMILE and femtosecond LASIK. In a series of more than 1,500 SMILE procedures, the same family as CLEAR (Ivarsen et al., 2014):

• Loss of suction during treatment occurred in 0.8% of eyes; almost all were successfully re-treated.
• Small tears at the incision occurred in 1.8%, and difficult removal of the tissue disc in 1.9%.
• 1.5% of eyes had lost two or more lines of vision with glasses at 3 months, but by an average of 18 months, vision was back within one line of where it started in every eye.

See CLEAR lenticule extraction.

PRK and TransPRK

PRK and TransPRK treat the surface of the cornea, so there is no flap. The trade-off is a slower recovery: the surface cells take several days to grow back, the eyes are sore for the first few days, and vision takes longer to sharpen (AAO EyeWiki).

• Haze, a faint scar that can blur vision, is the main specific risk. Mitomycin C, a medication applied briefly at the end of treatment, lowers the risk of haze (Chang et al., 2021). See PRK vs TransPRK vs ASA.
• Infection is rare but more likely after PRK than LASIK, because the surface is healing under a bandage contact lens: about 1 in 7,400 PRK procedures, compared with 1 in 22,000 LASIK procedures (Schallhorn et al., 2017).

See PRK and TransPRK recovery for the day-by-day recovery.

Rare but serious risks

Infection

Infection of the cornea (microbial keratitis) is rare. In a study of more than 645,000 laser eye surgery procedures, it followed about 1 in 22,000 LASIK and 1 in 7,400 PRK procedures (Schallhorn et al., 2017). Using your antibiotic drops as directed, and following your aftercare instructions, helps protect your eyes while they heal. See laser eye surgery recovery.

Corneal ectasia

Ectasia is a rare weakening of the cornea after laser eye surgery: it gradually bulges, and vision blurs. A systematic review estimated that, in eyes without risk factors before surgery, it occurred in about 90 per 100,000 eyes after LASIK, 20 per 100,000 after PRK and 11 per 100,000 after SMILE (Moshirfar et al., 2021). In a single-centre series of over 30,000 LASIK eyes followed for up to 8 years, it occurred in 0.033% (Bohac et al., 2018).

The main risk factors are a thin cornea and subtle irregularities in its shape before surgery (Bohac et al., 2018). That is why we map the shape and thickness of your corneas at your assessment, and recommend a different procedure, or no surgery, if your corneas aren’t suitable.

Can laser eye surgery make you blind?

Losing your sight from laser eye surgery is extremely rare. The complications that can permanently reduce vision, mainly infection and ectasia, are rare, and both are usually treatable when picked up early. The FDA notes that some patients lose lines of vision that can’t be corrected with glasses or contact lenses (FDA); in the 97-study review, this was 0.61% of eyes losing two or more lines (Sandoval et al., 2016).

How we lower your risk at Focus Vision

• Careful screening. Your assessment includes detailed mapping of the shape and thickness of your corneas, and checks for dry eye and other eye conditions. If laser eye surgery isn’t right for your eyes, we’ll tell you and explain the alternatives, such as an implantable contact lens.
• The right procedure for your eyes. LASIK, CLEAR and TransPRK each suit different eyes. See types of laser eye surgery.
• Treating dry eye first, if you have it, so your eyes heal well.
• A hospital-based laser. Our laser is in an accredited day hospital, the only hospital-based laser in Queensland. For LASIK and TransPRK, the eye tracker on our Alcon WaveLight EX500 laser follows your eye 1,050 times a second.
• Your own surgeon. Dr Brendan Cronin or Dr David Gunn performs your treatment and looks after you afterwards, with follow-up appointments for a year.

When to call us urgently

Call us straight away on (07) 3239 5005 if you have:

• increasing pain
• vision that is getting worse, rather than better
• a lot of redness
• increasing sensitivity to light.

These can be early signs of infection or inflammation, which need treating quickly.

Talk to us about your risks

The right question isn’t only “is laser eye surgery safe?” but “is it safe for my eyes?” To find out, book a free optometrist assessment at Focus Vision in Woolloongabba, Brisbane, or call (07) 3239 5005. See laser eye surgery in Brisbane and our costs.

References

1. Sandoval HP, Donnenfeld ED, Kohnen T, et al. Modern laser in situ keratomileusis outcomes. J Cataract Refract Surg. 2016;42(8):1224-1234. pubmed.ncbi.nlm.nih.gov/27531300
2. Solomon KD, Fernández de Castro LE, Sandoval HP, et al.; Joint LASIK Study Task Force. LASIK world literature review: quality of life and patient satisfaction. Ophthalmology. 2009;116(4):691-701. pubmed.ncbi.nlm.nih.gov/19344821
3. U.S. Food and Drug Administration. LASIK: What are the risks and how can I find the right doctor for me? fda.gov
4. Gunn DJ, Cox RA. StreamLight single-step transepithelial photorefractive keratectomy (PRK) for myopia and myopic astigmatism. J Ophthalmol. 2024;2024:5597457. pubmed.ncbi.nlm.nih.gov/39575318
5. Lobanoff MC, Mann PM II, Parikh M, Brenner J, Hall B. Multi-site study of patient reported vision quality and dry eye following LASIK. Clin Ophthalmol. 2026;20:566803. doi:10.2147/OPTH.S566803. doi.org/10.2147/OPTH.S566803
6. American Academy of Ophthalmology. Dry Eyes After Laser in situ Keratomileusis (LASIK). EyeWiki. eyewiki.org
7. Shen Z, Zhu Y, Song X, Yan J, Yao K. Dry eye after small incision lenticule extraction (SMILE) versus femtosecond laser-assisted in situ keratomileusis (FS-LASIK) for myopia: a meta-analysis. PLoS One. 2016;11(12):e0168081. pubmed.ncbi.nlm.nih.gov/27992482
8. Butt AB, Hanna A, Tohidi Kaloorazi M, et al. Incidence of femtosecond laser-assisted LASIK flap complications: a systematic review. J Cataract Refract Surg. 2026. doi:10.1097/j.jcrs.0000000000002031. pubmed.ncbi.nlm.nih.gov/42592790
9. Ivarsen A, Asp S, Hjortdal J. Safety and complications of more than 1500 small-incision lenticule extraction procedures. Ophthalmology. 2014;121(4):822-828. pubmed.ncbi.nlm.nih.gov/24365175
10. American Academy of Ophthalmology. Photorefractive Keratectomy. EyeWiki. eyewiki.aao.org/Photorefractive_Keratectomy
11. Chang YM, Liang CM, Weng TH, Chien KH, Lee CH. Mitomycin C for the prevention of corneal haze in photorefractive keratectomy: a meta-analysis and trial sequential analysis. Acta Ophthalmol. 2021;99(6):652-662. pubmed.ncbi.nlm.nih.gov/33326173
12. Schallhorn JM, Schallhorn SC, Hettinger K, Hannan S. Infectious keratitis after laser vision correction: incidence and risk factors. J Cataract Refract Surg. 2017;43(4):473-479. pubmed.ncbi.nlm.nih.gov/28532931
13. Moshirfar M, Tukan AN, Bundogji N, et al. Ectasia after corneal refractive surgery: a systematic review. Ophthalmol Ther. 2021;10(4):753-776. pubmed.ncbi.nlm.nih.gov/34417707
14. Bohac M, Koncarevic M, Pasalic A, et al. Incidence and clinical characteristics of post LASIK ectasia: a review of over 30,000 LASIK cases. Semin Ophthalmol. 2018;33(7-8):869-877. pubmed.ncbi.nlm.nih.gov/30359155