LASIK

LASIK (Laser-Assisted In Situ Keratomileusis) is a surgical procedure that uses a laser to permanently reshape the cornea — the clear, dome-shaped front surface of the eye — so that light focuses correctly on the retina and vision becomes sharper without glasses or contact lenses.

During LASIK, the surgeon creates a very thin flap on the surface of the cornea, lifts it, and then uses a cool ultraviolet laser called an excimer laser to remove a precise amount of corneal tissue underneath. This changes the curvature of the cornea. The flap is then laid back in place, where it bonds naturally without stitches. The whole process takes only a few minutes per eye.

LASIK is used to correct refractive errors — conditions where the shape of the eye prevents light from focusing properly. It is one of the most common elective (chosen, not emergency) vision-correction surgeries performed worldwide.

• Myopia (nearsightedness) — difficulty seeing objects far away clearly.
• Hyperopia (farsightedness) — difficulty focusing on objects close up.
• Astigmatism — blurred or distorted vision caused by an irregularly shaped cornea or lens.
• Mild combinations of the above, such as myopia with astigmatism.

LASIK is not suitable for everyone. Your eye doctor will assess whether your eyes meet the necessary criteria before recommending the procedure.

• Corneas that are too thin — not enough tissue can safely be removed.
• Very high degrees of refractive error that fall outside the safe treatment range.
• Keratoconus (a progressive thinning and cone-like bulging of the cornea) — LASIK can make this worse.
• Severe dry eye disease — the laser can worsen dryness significantly.
• Unstable prescription — if the glasses or contact lens power has changed within the past year or two, the eye has not yet settled.
• Certain autoimmune or connective-tissue diseases that affect wound healing.
• Pregnancy or breastfeeding, as hormones can temporarily affect corneal shape.
• Children and young teenagers whose eyes are still growing.

LASIK is generally considered safe, and serious complications are uncommon, but like any surgical procedure it carries recognised risks that a patient should understand before consenting.

• Dry eyes — the most common side effect; the corneal nerves that signal tear production are temporarily disrupted, causing dryness, burning, or grittiness, usually for weeks to months.
• Glare, halos, and starbursts — rings or rays of light around bright sources, especially at night, which are most noticeable in the early weeks and often improve over time.
• Undercorrection or overcorrection — the laser removes slightly too little or too much tissue, leaving some degree of refractive error; an enhancement (a second laser treatment) may be needed.
• Flap complications — the thin corneal flap may wrinkle, shift, or, rarely, develop an infection underneath it.
• Regression — vision may gradually drift back toward the original prescription over years, particularly in people with high myopia.
• Fluctuating vision — clarity may vary during the healing period, especially in the first weeks.
• Rarely, a significant loss of best corrected visual acuity (the sharpest vision achievable even with glasses), which in very rare cases may be permanent.
• Keratoconus-like ectasia (a bulging and weakening of the cornea after surgery) — rare, and most likely in eyes with pre-existing thin or irregular corneas.

Preparation for LASIK begins days or even weeks before the procedure. Soft contact lenses should be stopped for at least one to two weeks before all measurements are taken, and rigid gas-permeable lenses for longer — your doctor will give you a specific timeframe. Contact lenses change the shape of the cornea, and the cornea needs time to return to its natural form before the eye is mapped. Alcohol should be avoided in the days leading up to surgery, as it can affect healing. Smoking can impair circulation and wound repair, so doctors usually advise reducing or stopping it beforehand.

On the day of surgery, patients are usually asked to arrive without eye make-up, creams, or perfume on the face, as these can interfere with the laser. There is no requirement to fast (avoid eating) for LASIK, because only local anaesthetic (numbing eye drops — no injection, no general anaesthesia) is used. However, follow the specific instructions given by your surgical team.

Before the procedure is approved, your eye doctor will perform a thorough pre-operative assessment. Tests typically include:

• Corneal topography (detailed mapping of the cornea's surface shape) to detect any irregularities.
• Corneal pachymetry (measurement of corneal thickness) to confirm enough tissue is available.
• Pupil size measurement in low light conditions.
• Tear film assessment to check for pre-existing dry eye.
• Full refraction (measurement of your glasses prescription) taken without and sometimes with dilating eye drops.
• Slit-lamp examination (a microscope inspection of the front of the eye) to check for any disease or abnormality.

On the day of the procedure, the steps typically follow this order:

• 1. Numbing eye drops are applied; you remain awake and comfortable throughout.
• 2. An eyelid holder (speculum) is placed to keep the eye open gently.
• 3. A suction ring is applied briefly to stabilise the eye while the flap is created.
• 4. A microkeratome (a precise blade device) or a femtosecond laser creates the thin corneal flap.
• 5. The flap is carefully lifted and folded back.
• 6. You are asked to look at a fixed target light while the excimer laser reshapes the corneal tissue underneath. This part usually takes less than a minute per eye.
• 7. The flap is gently repositioned and smoothed back into place; it seals on its own.
• 8. A brief examination confirms the flap is correctly positioned before you leave the room.

Most patients notice improved vision within the first twenty-four hours, but full stabilisation usually takes several weeks to a few months. Immediately after the procedure, you will rest briefly in the clinic while staff check that the flaps are sitting correctly. You will not be able to drive yourself home, so you must arrange someone to accompany you. Your care team will prescribe antibiotic eye drops to prevent infection and anti-inflammatory eye drops to help healing, as well as lubricating drops for dryness; these are used for a set period as directed.

• Avoid rubbing your eyes — especially in the first weeks — as this can dislodge the corneal flap.
• Wear the protective eye shields provided, particularly during sleep, for as long as your doctor recommends.
• Avoid swimming pools, hot tubs, and contact with water that could carry bacteria for usually at least one month.
• Stay away from dusty or smoky environments during the early healing phase.
• Avoid eye make-up for at least one to two weeks, or until your doctor confirms it is safe.
• Reduce or avoid screen time for the first day or two to give the eyes initial rest.
• Wear good-quality sunglasses outdoors, as the eyes may be more sensitive to bright light during healing.
• Attend all scheduled follow-up appointments — these typically happen the day after surgery, then at one week, one month, and three months, though your clinic's schedule may differ.
• Report any sudden increase in pain, significant loss of vision, or discharge from the eye to your doctor promptly.
• Your doctor will advise when it is safe to return to contact sport, swimming, or any activity with a risk of eye impact.