Refractive surgery: evaluation, technique and responsible indication.

What is refractive surgery?

Refractive surgery aims to reduce dependence on glasses or contact lenses by correcting myopia, astigmatism, hyperopia or presbyopia in selected patients.

The laser changes corneal curvature to help focus light more accurately.

Corneal thickness, curvature and regularity are central to surgical planning.

Treatable refractive errors

• Myopia: distance vision is blurred.
• Hyperopia: near and sometimes distance vision may require effort.
• Astigmatism: vision may be distorted at different distances.
• Presbyopia: age-related difficulty focusing up close.

PRK

In PRK, the laser is applied on the corneal surface after removing the epithelium. Recovery tends to be slower in the first days, but it can be a good option for selected corneas.

LASIK

In LASIK, a corneal flap is created and the laser is applied underneath. Visual recovery is often faster, but not every cornea is suitable.

Preoperative evaluation

Topography, tomography, pachymetry, ocular surface evaluation and retinal assessment help define whether surgery is safe and which technique is appropriate.

Topography and tomography help identify corneal shape and risk patterns.

Contraindications

Suspicious or irregular corneas, unstable prescription, uncontrolled dry eye, certain retinal or systemic conditions and unrealistic expectations may contraindicate surgery or point to alternatives.

Alternatives

Some patients who are not ideal candidates for PRK or LASIK may be considered for phakic lenses, depending on anatomy and safety criteria.

Learn about phakic lenses.

Realistic expectations

The goal is to reduce dependence on glasses, not to promise perfect vision or zero future need for optical correction.