LASIK reshapes the cornea to correct how light focuses on the retina, reducing or removing dependence on glasses and contact lenses. It's a well-established procedure, but it isn't automatically right for everyone — eligibility depends on a handful of measurable factors, not just how strong your prescription is.
Corneal thickness and shape
LASIK works by reshaping a thin layer of corneal tissue, so there needs to be enough thickness to work with safely. Corneal topography also checks for irregularities such as early keratoconus, a thinning condition that would rule out standard LASIK in favour of alternative treatments.
A stable prescription
Your prescription should have been stable for at least a year before surgery. If your glasses or contact lens power is still changing, treating an eye that's still shifting can lead to results that drift again afterward — so we'll usually ask for recent prescription history at your screening.
Overall eye health
Conditions like dry eye, active infections or certain retinal issues can affect both candidacy and recovery, and are checked for during the pre-operative exam. Some of these are temporary and simply need treating first; others may mean LASIK isn't the right fit but an alternative refractive procedure is.
Age and general health
LASIK candidates are typically 18 or older, since vision can still be changing before that. Certain autoimmune conditions and pregnancy can also affect timing, and are discussed individually rather than treated as automatic disqualifiers.
The goal of the pre-operative screening isn't to find a reason to say no — it's to make sure that if we say yes, the results are safe and lasting.
What the screening involves
- Corneal thickness measurement (pachymetry)
- Corneal topography or contoura mapping
- Refraction and visual acuity testing
- Tear film and dry-eye assessment
- Pupil size measurement
- A full retinal examination
If LASIK isn't right for you
Patients who aren't suited to standard LASIK — often due to thinner corneas — may still be candidates for alternative procedures such as PRK, or may be better served by premium contact lenses. This is exactly why the screening happens before any commitment is made, not after.