Am I eligible for LASIK? Age, power and corneal thickness limits

“Am I eligible for LASIK?” is one of the most common questions I’m asked, usually followed by three more: Am I old enough? Is my power too high? Are my corneas thick enough? They’re exactly the right questions. Here are the honest answers, and what your options are if the answer is no.

Age: usually 18+, and stable

LASIK is for adult eyes. The general rule is 18 and above, but age alone isn’t the real test, stability is. Your prescription should have been more or less steady for about a year. If your power is still climbing, reshaping the cornea now just means you’d be short-sighted again later. That’s why we ask for your last year or two of prescriptions.

There’s a soft upper end too. From the mid-40s, you start needing reading glasses (presbyopia) regardless of LASIK, so the conversation shifts to what you actually want from your vision. LASIK can still be right, it’s just a fuller discussion.

Power: there’s a safe range, not a magic number

LASIK corrects short-sight, long-sight and astigmatism, but only within a safe range, because correcting more power means removing more corneal tissue. As a rough guide, laser comfortably handles short-sight up to around -8.00 to -10.00, depending on the eye, with smaller limits for long-sight and astigmatism.

The key word is depending on the eye, because power and thickness are linked. Which brings us to the one that matters most.

Corneal thickness: often the real deciding factor

This is the limit people least expect. LASIK works by removing a thin layer of corneal tissue, and your cornea has to be thick enough to give up that tissue and still have a safe, strong amount left behind.

• A thick, healthy cornea gives the laser room, and may safely allow a higher correction.
• A thin cornea can rule LASIK out even at a modest power.

That’s why two people with the same glasses number can get different answers: their corneas are different. We measure thickness and map the corneal shape before deciding anything, never from the prescription alone. It’s also how we screen for keratoconus, an irregular, weak cornea that rules laser out entirely.

If you don’t qualify for LASIK, you’re not out of options

Being told “no” to LASIK doesn’t mean glasses forever. Often it just means a different route fits your eyes better:

• SMILE Pro — flapless laser, gentler on dry eyes, good for many short-sighted eyes.
• ICL — an implanted lens that removes no corneal tissue, frequently the answer for high power or thin corneas.

A surgeon who only offers LASIK can only say yes or no. Because we offer all three, we can tell you which one, if any, genuinely fits, rather than forcing your eye to match the one procedure on the menu.

The only real way to know

Every limit above is a guide, not a verdict. The thing that actually settles it is a refractive suitability assessment: your prescription, corneal thickness and shape, and dry-eye status, measured together. From that, you get a straight answer, and if the honest answer is “not LASIK, but ICL,” or even “not yet,” we’ll tell you that too.

Wondering if you qualify? Check your LASIK suitability or compare LASIK vs SMILE Pro vs ICL. One assessment gives you the honest answer for your eyes.