What to Ask Before You Book LASIK

Refractive surgery is one of the most successful elective procedures in medicine and it is not right for everyone, which is an awkward combination when most of the detailed information available comes from organisations that perform it.

This practice does not do surgery. What follows is the list of questions worth having answered before you commit to anything.

How thick are my corneas

This is the question that most often produces a no, and it is the one to ask first.

LASIK works by removing corneal tissue to change its curvature. Enough tissue has to remain afterwards for the cornea to stay structurally stable. Remove too much and the cornea can begin to bulge forward over the following months or years, a serious complication called post refractive ectasia that behaves much like keratoconus.

How much tissue needs removing depends on your prescription. A higher prescription requires more removal, so a thin cornea and a high prescription together is the combination most likely to be ruled out.

Ask what your central corneal thickness is in microns, how much will be removed, and how much will remain.

What does my corneal topography show

Thickness alone is not sufficient. The shape matters too, because subtle early keratoconus is an absolute contraindication to LASIK and it is entirely invisible without topography.

Operating on a cornea with undetected early keratoconus reliably accelerates it. This is one of the more serious ways refractive surgery goes wrong, and it is preventable by mapping.

Ask whether topography was performed, whether it was normal, and whether there were any irregular findings.

Has my prescription been stable

Surgery corrects the prescription you have on the day of the procedure. If that prescription is still changing, you are correcting a moving target.

Most surgeons want at least a year of stability, and typically will not operate under twenty one because prescriptions commonly continue changing into the early twenties.

Bring old prescriptions. Two or three years of history makes stability immediately assessable, and it is one of the more useful things you can supply.

Do I have dry eye now

This is the most underestimated question on the list.

LASIK involves cutting a flap in the cornea, which severs corneal nerves. Those nerves are part of the feedback loop that tells the lacrimal gland to produce tears, so tear production drops during healing. Nerve regeneration takes months and is sometimes incomplete.

Someone with untreated dry eye going into surgery will have significantly worse dry eye afterwards, and post LASIK dry eye is among the most common causes of dissatisfaction with an otherwise technically successful procedure.

The right sequence is to have the ocular surface evaluated, treat anything found, and then be assessed for surgery. Not the other way round.

What will this not fix

Ask this one explicitly, because the answer is longer than most people expect.

• Presbyopia. From the mid forties you will need reading glasses regardless of how well the surgery goes, because that is the lens inside the eye ageing and corneal surgery does not touch it
• Cataract. It develops at the same rate afterwards and will eventually need surgery
• Glaucoma, macular degeneration and retinal disease. Risk is entirely unchanged
• The need for annual eye examinations, which remains exactly as it was

Someone having LASIK at thirty five and being delighted with it will still be reaching for reading glasses at forty five. That is not a failure of the surgery, and it surprises people who were not told.

What are my night vision risks

Halos, starbursts and glare at night are recognised effects, and the risk is higher with large pupils and with higher prescriptions requiring larger treatment zones.

Ask whether your pupil size was measured in dim conditions and how it compares with the planned treatment zone. If you drive at night for work, this deserves more weight than it usually gets.

What happens if it needs adjusting

Enhancement procedures are possible when sufficient corneal tissue remains, which is another reason the thickness numbers matter.

Ask what the enhancement policy is, what it costs, over what period it applies, and whether you will have enough remaining thickness to be a candidate for one.

Who does the follow up

Post operative care runs for months, not days. Ask where those visits happen, how many there are, and who conducts them.

Co-management means your optometrist handles the follow up locally, which for most people means short journeys rather than repeated trips to a surgical centre, and it means the person reviewing your healing has your pre operative measurements to compare against.

What if I am not a candidate

Worth asking, because the answer is rarely nothing.

Ortho-K is the closest alternative to what LASIK delivers day to day, and because nothing is removed, thin corneas rarely rule it out. It is also fully reversible and available under twenty one. PRK suits some corneas too thin for LASIK, and implantable lenses suit very high prescriptions.

The alternatives, compared properly

If the answer to candidacy is no, or if you would rather not have surgery, there are three real alternatives and they suit different situations.

• Ortho-K. Overnight lenses, fully reversible, thin corneas rarely a barrier, available under twenty one, and it slows myopia progression in children. The trade is nightly wear.
• PRK. Surface ablation with no flap. Suits some corneas too thin for LASIK and is preferred in some contact sports and occupations where a flap is a concern. Recovery is several days and genuinely uncomfortable.
• Implantable collamer lens. A lens placed inside the eye without removing corneal tissue. Suits very high prescriptions beyond corneal surgery's range. It is intraocular surgery, which is a different risk category from corneal surgery.

Being told no for LASIK is frequently a yes for one of these, which is why the assessment is worth having even if surgery turns out not to be the answer.

Questions about the surgeon, not just the procedure

Most people research the procedure thoroughly and the surgeon barely at all, which is the wrong way round.

• How many of this specific procedure do you perform a year?
• What is your enhancement rate, and what does an enhancement cost?
• Who sees me if something goes wrong at two in the morning?
• What happens if I am unhappy with the result and you consider it a technical success?
• Will you show me my own corneal maps and talk me through them?

That last one is a good general filter. A surgeon happy to show you your own data and explain the reasoning is in a different category from one who presents a yes or no.

The recovery nobody describes

Marketing describes the procedure. The fortnight afterwards gets less attention.

• Day one. Functional vision for most people, often described as watery and slightly hazy. A protective shield at night for the first few nights.
• Week one. Vision usually good and fluctuating through the day. Dry eye typically at its worst, and drops are used frequently rather than occasionally.
• Weeks two to four. Fluctuation reducing. Night time halos and starbursts are common at this stage and usually diminish.
• Months two to six. Vision stabilising, dry eye improving gradually. The final result is judged here, not earlier.
• A small minority experience dry eye persisting well beyond six months.

Plan for the first week rather than assuming a day off is enough, particularly if your work is screen heavy.

The single most useful preparation

Have your ocular surface assessed and treated before you are measured, not after you have booked.

Untreated dry eye going into refractive surgery does two things. It makes the pre operative measurements less reliable, which affects the accuracy of the correction. And it reliably becomes worse afterwards, because the procedure temporarily reduces tear production regardless of where you started.

Treating it first takes weeks, delays nothing meaningfully, and improves both the accuracy and the comfort of the outcome. It is the highest value thing on this page and almost nobody does it.

What co-management actually changes for you

Co-management is presented as an administrative arrangement and it has concrete practical consequences worth understanding.

• Your follow up happens locally. Post operative care runs for months, not days, and the difference between short journeys and repeated trips to a surgical centre is substantial when there are five or six of them.
• The person reviewing your healing holds your pre operative measurements. Judging whether a cornea is settling as expected requires knowing what it looked like beforehand.
• The candidacy advice comes from somewhere with no financial interest in the answer. A practice that does not perform surgery has no reason to tell you that you are a candidate when you are not.
• Someone independent is watching for the complications. Dry eye, night vision effects and regression are all things a patient may hesitate to raise with the surgeon who performed the procedure and will raise readily elsewhere.

It also means that if the answer is no, the conversation continues rather than ending, because the alternatives are things the same practice provides.