Complications, With Their Real Rates.
Every procedure on this site works for most people, about 94 to 95 percent reach 20/20 with the lasers (PMID 39641610), and every one of them has a complication ledger the consult should read aloud. Here is that ledger, procedure by procedure, with published rates instead of adjectives.
By procedure, by number.
| Procedure | Signature risks | Published rates |
|---|---|---|
| LASIK | Dry eye; flap-related issues; night-vision effects; ectasia on weak corneas | 60–70% dry eye at 1 mo → 20–40% at 6 mo (PMC11110473) |
| PRK | Surface pain days 1–7; haze (mitigated by mitomycin-C); slower visual recovery | dry eye generally below LASIK long-term |
| SMILE | Same family as LASIK, smaller scale; suction loss; lenticule issues (rare) | less dry eye than LASIK, not zero (PMC5161410) |
| EVO ICL | Endothelial cell loss; elevated IOP; anterior subcapsular cataract; halos | cataract risk reduced (not eliminated) by EVO design (PMC11110473) |
| RLE (multifocal) | Dysphotopsias; retinal detachment, anatomy-dependent | 74% halos / 81% night glare (PMC4258327); RD ~0.08% presbyopes → 1.5–8% high myopes (PMC7856935, PMC5584899) |
The pattern worth internalising: corneal procedures concentrate risk on the surface and tear film; intraocular procedures move it to structures that do not regenerate. Neither family is "the safe one", they are different ledgers for different eyes.
"Complications are one-in-a-million."
The serious sight-threatening events are indeed rare. But the common complications are genuinely common: most LASIK patients experience dry eye early on (PMC11110473), and most diffractive multifocal-IOL patients see halos at night (PMC4258327). Honest consent treats the frequent-but-manageable and the rare-but-serious as two different conversations, and has both.
Three questions that sort any consult.
- "What are my numbers?" Corneal thickness, predicted residual bed, topography pattern, chamber depth, axial length. The gates exist because they map to the ledger above; an eye inside every gate carries the published rates, an eye squeezed past a gate carries worse ones. Check yourself in the candidacy guide and the matcher.
- "Which of these rates applies to my anatomy?" The RLE detachment span, 0.08 percent versus 1.5 to 8 percent, is the textbook case (PMC7856935): same procedure, different eye, hundred-fold different risk.
- "What happens if I'm in the unlucky percent?" Dry eye has a management ladder; halos have adaptation time and lens-exchange as a last resort; retinal detachment has urgent surgery with its own outcomes. A clinic fluent in the remedies is a clinic that has seen the complications.
Frequently asked questions
What is the most common complication of laser eye surgery?
Dry eye, by a wide margin: 60 to 70 percent of LASIK patients report symptoms at one month, settling to 20 to 40 percent at six months and beyond (PMC11110473). SMILE produces measurably less because its small incision severs fewer corneal nerves, less, not none.
How often does LASIK fail to deliver 20/20?
In the head-to-head evidence, about 95 percent of LASIK eyes and 94 percent of PRK and SMILE eyes reach 20/20 uncorrected (PMID 39641610). Strong odds, but five or six eyes in a hundred fall short of the marketing line, which is why "20/20 guaranteed" is on our refuted list.
Which procedure has the most serious risks?
They differ in kind. Corneal lasers risk surface problems: dry eye, night-vision effects, rare ectasia on weak corneas. The ICL and RLE move risk inside the eye: endothelial cell loss, pressure, cataract for the ICL; retinal detachment, up to 1.5–8% in high myopes, for RLE (PMC7856935). "Most serious" depends on which eye is on the table.
Are halos after surgery permanent?
Often they fade as the brain adapts, and most patients tolerate them, the multifocal-IOL series with 74 percent halos still scored a median 4-out-of-5 satisfaction (PMC4258327). But some persist, and people who drive at night professionally should treat dysphotopsia rates as a primary decision factor, not a footnote.
How do I minimise my own complication risk?
Pick the procedure that fits your anatomy rather than the one being promoted: the gates exist because they map to complications. Insist on the full pre-op workup, topography, pachymetry, dry-eye testing, biometry for intraocular options, and on hearing your numbers, not the brochure’s. Our matcher applies the published gates honestly.