Stop Wearing Contact Lenses Before Your Exam

The instruction that gets missed most often

Of all the preparation for a vision correction assessment, this is the one that most often goes wrong: contact lenses have to come out well before the examination, not on the morning of it.

Patients who fly in wearing lenses sometimes have to have measurements repeated on a later day. For someone travelling from another country on a fixed schedule, that is a day out of a trip that was already tight.

Why lenses interfere

Contact lenses sit directly on the cornea and change its shape slightly while worn. The change is small and normally reverses, but it does not reverse instantly.

The examination for vision correction depends on precise corneal measurements: thickness across the surface, curvature of the front and back, and the pattern of any irregularity. If those measurements are taken while the cornea is still holding the shape a lens imposed, the result describes the lens rather than your eye.

An eye measured too soon can look like a different candidate than it actually is. That is the whole problem, and it is why the interval is not negotiable in the way patients sometimes hope.

Soft and rigid lenses are not the same

Soft lenses generally require a shorter break. Rigid gas-permeable lenses require considerably longer, because they shape the cornea more firmly and the cornea takes longer to return.

Orthokeratology lenses, worn overnight specifically to reshape the cornea, require the longest interval of all, for exactly the reason they work.

The number of days for your situation depends on which type you wear, how long you have worn them, and how many hours a day. Ask the clinic for your specific interval rather than assuming a general figure applies, because getting this wrong costs a day of your trip.

What to do in the meantime

Wear glasses. If you do not own a current pair, this is worth sorting out before travelling rather than after arriving, since being unable to see comfortably for several days in an unfamiliar city is avoidable.

Bring your lens details with you: the type, the brand, the prescription and roughly how long you have worn them. These feed into how the measurements are interpreted.

If you cannot manage the full interval for a practical reason, say so before you travel rather than on arrival. There may be a way to arrange the schedule around it, and there certainly is not one if the clinic finds out on the day.

Why this matters more for international patients

Someone living locally who arrives too soon reschedules for next week. Someone who has flown in loses a day they cannot get back, and in a short trip that can push the surgery date outside the stay entirely.

This is the reason we confirm the interval in advance for every patient travelling from Mongolia, and the reason we ask about lens type at the enquiry stage rather than at the examination.

Before you book

Tell us what lenses you wear when you first get in touch. We will confirm the interval that applies to you, so it can be built into the travel dates rather than discovered afterwards. Consultation is available in Mongolian, and our coordination team handles the records side before you arrive.

FAQ

How many days before the exam should I stop wearing lenses?

It depends on the lens type, how long you have worn them and for how many hours a day. Soft lenses need a shorter break than rigid ones. Ask for your specific interval rather than relying on a general number, because getting it wrong costs a day of your trip.

What happens if I arrive still wearing them?

The measurements may have to be repeated on a later day, because a cornea shaped by a lens produces readings that describe the lens rather than your eye. For a short trip that can move the surgery date outside your stay.

I wear overnight reshaping lenses. Is that different?

Yes, considerably. Orthokeratology lenses are designed to reshape the cornea, so the interval before accurate measurement is the longest of any lens type. Tell us at the enquiry stage as it strongly affects your travel planning.

I do not have glasses. What should I do?

Arrange a current pair before travelling. Managing several days without lenses in an unfamiliar city is much harder without glasses, and it is easier to solve at home than after arrival.