What you need to know before having LASIK surgery

08/07/2025

It is a safe and quick procedure that helps reduce or eliminate dependence on glasses and contact lenses.

LASIK surgery is an advanced ophthalmological procedure that corrects refractive errors such as myopia, hyperopia and astigmatism. However, before undergoing this operation, it is essential to understand its requirements, benefits and possible risks.

What should you know before LASIK surgery?

Before deciding on LASIK surgery, it’s important to understand how it works, what to expect from the procedure, and whether you are a suitable candidate. It’s also key to be aware of the pre- and post-operative care needed to ensure optimal recovery.

Requirements for LASIK surgery

Not everyone is suitable for this surgery. The main requirements for undergoing LASIK include:

• Being over 18 years of age
• Having a stable prescription with no significant changes in recent years
• Not suffering from eye diseases such as keratoconus, glaucoma or cataracts that could contraindicate the surgery
• Not being pregnant or breastfeeding
• Not taking medication that could interfere with the surgery
• Not presenting any contraindications in the preoperative tests performed by the ophthalmologist

The ophthalmologist will carry out preliminary tests to determine whether the patient meets these criteria.

Who can have LASIK surgery?

LASIK is ideal for people with:

• Myopia (difficulty seeing far away)
• Hyperopia (difficulty seeing up close)
• Astigmatism (blurred or distorted vision)

However, those with an unstable prescription, thin corneas or pre-existing eye conditions may not be suitable candidates.

How to prepare for LASIK surgery: step by step

The pre-surgery protocol includes several stages to ensure the success of the procedure:

Initial visit

• If you wear contact lenses, you will need to stop using them 48 hours before the consultation
• An optometric exam will be performed to measure visual acuity and prescription
• A corneal topography will be done to analyse the shape of the cornea and determine the most appropriate technique
• A consultation with the ophthalmologist will evaluate the general condition of the eye and address any questions

Preoperative tests

The day before surgery, further tests will be conducted to confirm that everything is in optimal condition and to ensure a safe procedure.

Day of the surgery

• The surgery is outpatient and lasts approximately 15 minutes
• After the operation, the patient stays under observation for 30 minutes before going home with their eyes uncovered

Follow-up appointments

• A first check-up is done the day after the surgery
• A second check-up takes place about a month later to assess the stability of the visual correction

How long does LASIK recovery take?

Recovery from LASIK is quick. Most patients notice an improvement in vision within 24 to 48 hours. However, some side effects such as dry eyes and light sensitivity may last for a few weeks. It is recommended to:

• Avoid rubbing your eyes and use artificial tears
• Refrain from contact sports and swimming for at least a month
• Protect your eyes from dust and bright light

What are the risks of LASIK surgery?

Although it is a safe procedure, LASIK may cause side effects in some cases, such as:

• Temporary dry eyes
• Halos or glare at night
• Light sensitivity

Most of these symptoms fade over time or with proper treatment.

When are the results of LASIK noticeable?

Patients usually notice an almost immediate improvement, although vision stabilises completely within a few weeks. Most achieve their best visual acuity between the first and third month after surgery.

LASIK surgery is an effective option to correct refractive errors and reduce dependence on glasses and contact lenses. With an accurate diagnosis and by following medical advice, the results can be both optimal and long-lasting.

Dr Andrés Picó, ophthalmologist at the Barraquer Ophthalmology Centre