Laser Eye Surgery: Types, Suitability, Recovery and Risks

Laser eye surgery is a form of refractive treatment used to correct focusing problems such as myopia, hyperopia and astigmatism. The procedures work by reshaping the cornea, the transparent front surface of the eye.

Different techniques reach the corneal treatment area in different ways. Some create a corneal flap, while others treat the surface without a conventional flap. The appropriate technique depends on factors including prescription, corneal thickness and shape, dry-eye status and overall eye health.

Laser vision correction can reduce dependence on glasses or contact lenses, but it cannot guarantee that corrective lenses will never be needed again. Residual refractive error, presbyopia, cataracts and other later changes can still affect vision.

Laser Eye Surgery: Quick Answer

Laser eye surgery reshapes the cornea to correct refractive errors such as myopia, hyperopia and astigmatism. Femto LASIK creates a corneal flap, while surface procedures such as PRK-LASEK and No-Touch Laser avoid a conventional LASIK flap. The appropriate technique depends on corneal measurements, prescription stability, ocular-surface health and a complete eye examination.

What Is Laser Eye Surgery?

Laser eye surgery commonly refers to refractive procedures that reshape the cornea to change how light is focused inside the eye.

The cornea contributes significantly to the eye’s focusing power. When light is not focused correctly onto the retina, a refractive error occurs.

Common refractive errors include:

• Myopia, or nearsightedness
• Hyperopia, or farsightedness
• Astigmatism

Laser treatment changes corneal curvature to improve focusing.

The exact procedure depends on the patient’s measurements, refractive error and eye health.

What Types of Laser Eye Surgery Are Available?

Several laser techniques are used for refractive correction.

At Avicenna International Hospital’s Eye Center, currently listed excimer-laser options include:

• Femto LASIK (i-LASIK)
• PRK-LASEK
• No-Touch Laser

These procedures have the same broad goal of correcting refractive error but differ in how the cornea is accessed and how the surface heals afterwards.

What Is Femto LASIK?

LASIK stands for laser-assisted in situ keratomileusis.

During LASIK, a thin flap is created in the cornea. The flap is lifted, and an excimer laser reshapes the underlying tissue according to the planned correction. The flap is then repositioned.

With Femto LASIK, a femtosecond laser is used to create the flap rather than a mechanical blade.

For appropriately selected patients, one advantage of LASIK is relatively rapid early visual recovery.

However, creating a flap also introduces considerations that do not apply in the same way to flap-free surface procedures.

What Is PRK?

PRK stands for photorefractive keratectomy.

PRK reshapes the cornea without creating a LASIK flap.

Instead, the epithelial layer on the front surface of the cornea is removed before an excimer laser reshapes the underlying tissue.

The epithelium then regenerates during healing.

A temporary bandage contact lens is commonly placed over the eye while the surface heals.

Because the epithelium must regrow, early visual recovery is generally slower and discomfort can be more noticeable than after LASIK.

What Is LASEK?

LASEK is another surface-ablation procedure.

Like PRK, it avoids creating a conventional LASIK flap.

The main technical difference concerns how the corneal epithelial layer is managed during treatment.

PRK and LASEK are therefore related procedures but are not technically identical.

The choice should depend on the patient’s eye measurements and the ophthalmologist’s treatment plan rather than the procedure name alone.

What Is No-Touch Laser?

“No-Touch Laser” is commonly used to describe a transepithelial surface-laser technique.

Unlike LASIK, it does not require creation of a conventional corneal flap.

The precise treatment method can differ according to the laser platform and protocol.

Patients should therefore ask which specific technique is being proposed and how the epithelial surface will be treated rather than relying only on the term “No-Touch”.

LASIK vs PRK: What Is the Difference?

The main difference is how the cornea is accessed before laser reshaping.

Feature	Femto LASIK	PRK / Surface Treatment
Corneal flap	Yes	No
Surface epithelium	Mostly preserved through flap approach	Removed or treated
Early visual recovery	Generally faster	Generally slower
Early discomfort	Usually less	Often more noticeable
Bandage contact lens	Usually not needed for epithelial healing	Commonly used
Flap-related complications	Possible	No LASIK flap
Corneal considerations	Requires sufficient tissue for flap and treatment	May be considered in selected cases
Main goal	Refractive correction	Refractive correction

Neither technique is automatically better for every patient.

The appropriate choice depends on corneal anatomy, refractive error, ocular-surface health, lifestyle and other examination findings.

For a more detailed side-by-side comparison, see our LASIK vs PRK guide.

Which Vision Problems Can Laser Eye Surgery Treat?

Laser eye surgery may be considered for several refractive errors.

Myopia

Myopia causes distant objects to appear blurred while nearby objects may remain clearer.

Laser treatment changes corneal shape to alter its focusing power.

Hyperopia

Hyperopia can make near vision more difficult and may also affect distance vision depending on its severity and the patient’s age.

Selected patients may be suitable for laser correction.

Astigmatism

Astigmatism results from irregular focusing caused by the shape of the cornea or other optical structures.

Laser treatment can correct some forms of astigmatism in appropriately selected patients.

A glasses prescription alone is not enough to establish suitability for surgery.

Who May Be Suitable for Laser Eye Surgery?

Suitability is assessed individually.

Factors commonly considered include:

• Age
• Stability of the prescription
• Corneal thickness
• Corneal shape
• Corneal topography or tomography
• Type and degree of refractive error
• Tear-film quality
• Dry-eye symptoms
• Pupil characteristics
• Previous eye surgery
• Other eye conditions
• General medical history
• Current medication
• Occupation and lifestyle
• Visual expectations

Not everyone who wears glasses or contact lenses is suitable for refractive laser surgery.

Why Is Corneal Mapping Important?

Corneal mapping provides detailed information about corneal shape and structure.

This is important because the eye can appear healthy during a basic examination while still having features that make corneal laser treatment unsafe or unsuitable.

Corneal mapping can help identify:

• Irregular corneal shape
• Abnormal thickness
• Possible keratoconus
• Signs of corneal instability

The decision should therefore be based on measured anatomy rather than prescription strength alone.

What Is Keratoconus?

Keratoconus is a condition in which the cornea gradually thins and changes shape.

It is particularly important in refractive-surgery assessment because removing tissue from an unstable cornea can create serious complications.

Patients with suspected keratoconus or other signs of corneal instability require detailed ophthalmic assessment.

Being unsuitable for LASIK because of corneal instability does not automatically mean that PRK or another surface treatment is appropriate.

Can People With Thin Corneas Have Laser Eye Surgery?

Sometimes, but corneal thickness cannot be considered in isolation.

Surface treatments such as PRK may be considered in some patients because they avoid creation of a LASIK flap.

However, a relatively thin cornea still needs detailed structural assessment.

The ophthalmologist may also consider:

• Corneal shape
• Refractive error
• Amount of correction required
• Expected remaining corneal tissue
• Evidence of corneal stability

A structurally unsuitable cornea should not simply be treated with a different laser technique.

What About Dry Eyes?

Dry-eye status is an important part of refractive-surgery assessment.

LASIK can worsen dry-eye symptoms in some patients.

Surface procedures can also produce temporary ocular-surface symptoms, so PRK should not be considered a guarantee against postoperative dryness.

Patients with significant dry eye may need treatment of the ocular surface before any laser procedure is considered.

Who May Not Be Suitable for Laser Eye Surgery?

Laser treatment may need to be postponed, modified or avoided when factors such as the following are present:

• Unstable refractive prescription
• Keratoconus or suspected corneal instability
• Insufficient corneal thickness
• Significant untreated dry eye
• Active eye infection or inflammation
• Certain corneal diseases
• Other eye disorders
• Pregnancy or breastfeeding when measurements are unstable
• Medical conditions that may affect healing
• Certain medications
• Expectations that cannot reasonably be achieved

Not qualifying for one refractive procedure does not automatically mean that another technique is appropriate.

What Happens Before Laser Eye Surgery?

A detailed ophthalmic examination is required before treatment.

Assessment may include:

• Glasses or contact-lens prescription
• Prescription stability
• Corneal thickness
• Corneal topography or tomography
• Tear-film assessment
• Dry-eye evaluation
• Pupil characteristics
• General eye health
• Previous eye procedures
• Medical history
• Medication use

Contact lenses can temporarily alter corneal shape, so patients may need to stop wearing them before measurements.

The required interval depends on the type of lenses and the ophthalmologist’s instructions.

What Happens During Femto LASIK?

The eye is numbed using anaesthetic drops.

During Femto LASIK:

1. A femtosecond laser creates a thin corneal flap.
2. The flap is lifted.
3. An excimer laser reshapes the underlying cornea.
4. The flap is repositioned.

Sutures are not typically required.

After treatment, the patient follows a postoperative eye-drop and examination schedule determined by the ophthalmologist.

What Happens During PRK or Surface Laser Treatment?

The eye is also numbed with anaesthetic drops.

During PRK:

1. The corneal epithelial surface is removed.
2. An excimer laser reshapes the underlying tissue.
3. A temporary bandage contact lens is generally applied.
4. The epithelial layer regenerates during healing.

Because the corneal surface must heal, early recovery is generally slower than with LASIK.

Is Laser Eye Surgery Painful?

Anaesthetic eye drops are used during treatment.

Patients may notice pressure, light or unusual sensations during the procedure rather than conventional surgical pain.

The early postoperative experience differs according to technique.

LASIK usually causes less early discomfort.

PRK and other surface treatments can cause more irritation while the epithelium heals, including:

• Burning
• Stinging
• Watering
• Light sensitivity
• Foreign-body sensation

Individual experiences vary.

How Long Does Recovery Take?

Recovery depends considerably on the procedure performed.

Recovery After LASIK

Early vision generally improves more quickly.

Some patients return to many routine activities relatively soon, but driving, work and other activities should resume only when vision is adequate and the ophthalmologist considers it appropriate.

Recovery After PRK or Surface Treatment

Recovery is slower because the epithelial layer needs to regenerate.

A bandage contact lens may be used during early healing.

Vision can fluctuate while the surface heals and continues to stabilise.

For both procedures, complete visual stabilisation can take longer than the first stage of recovery.

When Can You Drive After Laser Eye Surgery?

There should not be a universal promise that every patient can drive the following day.

Driving should resume only when:

• Vision meets the required standard
• The patient feels visually comfortable
• Postoperative symptoms do not interfere with safe driving
• The treating ophthalmologist considers it appropriate

Recovery differs between LASIK and surface procedures, and night vision can take additional time to stabilise.

What Are the Risks of Laser Eye Surgery?

Possible side effects and complications include:

• Dry-eye symptoms
• Glare
• Halos
• Starbursts
• Ghosting or double images
• Light sensitivity
• Under-correction
• Over-correction
• Residual refractive error
• Infection
• Inflammation
• Corneal healing problems
• Reduced visual quality
• Need for additional treatment

LASIK also has flap-specific risks that do not occur in the same way with flap-free surface procedures.

Rare but serious complications are possible, which is why patient selection, examination and informed consent are important.

Can Laser Eye Surgery Cause Night-Vision Problems?

Yes.

Patients can experience symptoms such as:

• Halos around lights
• Glare
• Starbursts
• Ghosting
• Reduced visual quality in dim conditions

These symptoms may improve as the eyes recover but can remain significant for some patients.

People who drive frequently at night or depend heavily on low-light vision for work should discuss this before treatment.

Does Laser Eye Surgery Permanently Eliminate Glasses?

No refractive procedure should be presented as guaranteeing lifelong freedom from glasses.

Laser surgery corrects the refractive error present at the time of treatment, but the eyes can continue to change.

Glasses may later be needed because of:

• Residual refractive error
• Recurrent refractive change
• Presbyopia
• Cataracts
• Changes in the natural lens
• Other eye diseases

A good initial laser result therefore does not mean that vision will remain unchanged for life.

What Is Presbyopia?

Presbyopia is the age-related reduction in the eye’s ability to focus on nearby objects.

It mainly results from changes in the natural lens rather than the cornea.

Laser correction of distance vision does not prevent presbyopia.

A patient who sees clearly at distance after treatment may therefore still need reading glasses later.

Can Cataracts Develop After Laser Eye Surgery?

Yes.

Laser refractive surgery reshapes the cornea. It does not prevent age-related changes in the natural lens.

Cataracts can therefore still develop later in life.

Patients should inform future ophthalmologists that they have previously had refractive surgery because this information can be relevant when cataract surgery and intraocular-lens calculations are planned.

Can Your Prescription Return After Laser Treatment?

Yes.

Residual or recurrent refractive error can develop after surgery.

This does not automatically mean the original treatment failed.

The eye is a biological system and can continue to change with age.

Any decision about further treatment requires a new examination and assessment of whether additional correction is safe and appropriate.

Can Laser Eye Surgery Be Repeated?

Additional refractive treatment may be possible in selected patients, but this should never be assumed in advance.

Suitability depends on factors including:

• Remaining corneal tissue
• Corneal shape
• Current prescription
• General eye health
• Previous procedure
• Reason for the visual change

Further treatment is not possible or appropriate for every patient.

LASIK or Surface Laser: Which Is Better?

Neither is universally better.

LASIK may appeal to suitable patients because early visual recovery is generally faster and discomfort tends to be lower.

A surface treatment may be considered in selected patients because it does not create a conventional LASIK flap.

Factors influencing the choice include:

• Corneal thickness
• Corneal shape
• Refractive error
• Dry-eye status
• Lifestyle
• Occupation
• Eye-trauma risk
• Recovery priorities

Treatment should be selected according to the individual eye rather than which procedure sounds newer or is advertised more heavily.

Laser Eye Surgery for International Patients

Patients travelling for refractive surgery should allow enough time for both proper assessment before treatment and appropriate postoperative follow-up.

Before treatment, useful questions include:

• Which procedure is being recommended?
• Why is it appropriate for my eyes?
• Which measurements are required?
• Are there other suitable options?
• What should I expect during recovery?
• When is the first postoperative examination?
• When can I travel?
• When can I drive?
• Which eye drops will I need?
• What should I do if symptoms develop after returning home?

An online consultation may help with preliminary planning, but final suitability requires an ophthalmic examination and appropriate eye measurements.

Laser Eye Surgery at Avicenna International Hospital

At Avicenna International Hospital’s Eye Center in Istanbul, patients with refractive errors including myopia, hyperopia and astigmatism can be assessed for laser vision correction.

Currently listed excimer-laser options include:

• PRK-LASEK
• No-Touch Laser
• Femto LASIK (i-LASIK)

Treatment selection is based on factors such as the patient’s prescription, corneal thickness and shape, ocular-surface condition, overall eye health and findings from the ophthalmic examination.

Not every patient is suitable for laser eye surgery, and the correct technique cannot be determined reliably from prescription numbers alone.

For international patients, previous prescriptions and ophthalmic reports may assist with preliminary review, but final treatment planning requires clinical examination.