Dry eye after laser eye surgery: what the timeline actually tells us

The rate moved quite a lot over three months

A 2026 retrospective study tracked 3,000 people after femtosecond LASIK. It counted dry eye when the Ocular Surface Disease Index, a symptom questionnaire, reached 13 or more. The result was 25% at one week, 38% at one month and 15% at three months.

So which one is the dry-eye rate? All three, for that particular group and definition. The rise at one month and fall by month three tell a much better story than a single percentage stripped from the timeline.

Women and people who already had dry eye had higher odds of postoperative symptoms in this study. But the research came from one center, looked back at existing records and stopped at three months. It cannot tell us how many symptoms persisted beyond that point, and its exact percentages should not be treated as universal.

Feeling dry and testing dry are not always the same

For one person, dry eye means burning or a gritty feeling. For another, it is blur that clears after a blink or a lubricating drop. Pain and light sensitivity can enter the picture too. A questionnaire captures that lived experience. Tear break-up time, staining, tear production and meibomian-gland tests each inspect a different part of the surface.

One meta-analysis found reduced tear production and tear break-up time after LASIK. The pooled changes after SMILE and PRK were not statistically significant in that analysis. That is not proof that SMILE or PRK never causes dryness. It tells us that this set of studies, with its measurements and uncertainty, did not show the same pooled effect.

Two papers can sound contradictory simply because one asked patients how they felt and the other measured tears. Whenever you see a dry-eye percentage, find out whether it came from symptoms, an examination, a treatment requirement or a clinician’s diagnosis.

The baseline deserves more attention

The tear film is part of the eye’s optics, not just its comfort system. When it is unstable, preoperative scans and refractions can be less repeatable. Treating the surface and measuring again may change the surgical plan. Occasionally it changes the decision to operate at all.

The FDA warns that LASIK can aggravate dry eye and includes tear production in its preoperative checklist. A quick “Do your eyes feel dry?” is not much of an assessment. Contact-lens tolerance, long screen days, current drops, eyelid inflammation, staining and the consistency of repeat measurements all add context.

Existing symptoms do not automatically rule surgery in or out. They do mean that the starting point and the follow-up plan need to be taken seriously.

A population curve is not a diagnosis

Knowing that symptoms are common early can be reassuring, but it does not make every painful or worsening eye routine. The reverse is also true: a rough first month does not prove that the problem will be permanent.

What matters day to day is the direction of travel. Is it improving, flat or getting worse? Does the blur change after blinking? Is one eye much worse? Is the treatment doing anything? Most importantly, has someone examined the surface and explained what they found?

Severe or urgent symptoms need clinical assessment, not comparison with an online average. Sudden loss of vision, increasing pain, pronounced redness, discharge or rapidly worsening light sensitivity should not wait for a blog or a forum reply.

The less catchy version is the honest one

“Thirty-eight percent had dry eye” makes a neat headline. The accurate version is longer: 38% of 3,000 FS-LASIK patients met a symptom-score threshold at one month in a retrospective study from one center.

It is not elegant, but it keeps an early symptom rate from turning into a claim about permanent complications. It also stops a LASIK result drifting into a discussion about every other refractive procedure.