+What is Laser Vision Correction Surgery?

Laser vision correction surgery (or refractive eye surgery) refers to any surgical treatment using lasers to correct problems such as myopia, hyperopia and astigmatism. The treatment works by reshaping or polishing the cornea (the clear front portion of the eye) so that light traveling through it is properly focused onto the retina for a sharp and clear image. There are many types of vision correction surgeries and these include ReLEx® SMILE (Refractive Lenticule Extraction, Small Incision Lenticule Extraction), LASIK (Laser-Assisted in Situ Keratomileusis) and Surface ablation procedures such as Photorefractive Keratectomy (PRK), Laser Epithelial Keratomileusis (LASEK) or Epithelial Laser in Situ Keratomileusis).

+How does Laser Vision Correction / ReLEx SMILE Surgery Improve Your Quality of Life?

ReLEx® SMILE surgery aims to reduce the dependency on spectacles and contact lenses in order to improve the quality of life. Studies have shown that quality of life is reduced in spectacle wearers, particularly those with higher corrections. Read more about this topic at the US National Library of Medicine. Quality of Life Study: ReLEx® Eye Surgery vs. Corrective Lenses.

+What is LASIK?

LASIK (Laser assisted in-situ keratomileusis) is one of the most popular laser vision correction procedures. A corneal flap is created using a femtosecond laser or mechanical microkeratome. If the femtosecond laser is used to create the flap, then the procedure is considered ‘Bladeless’. The corneal flap is folded back to expose the underlying corneal bed and to allow excimer laser ablation to occur. Laser excimer ablation is necessary to reshape the corneal surface so that refractive errors can be treated. The flap is then replaced back into its natural position and smoothened. LASIK is performed with numbing eye drops only and both eyes are usually treated at the same time.

The entire process may take around 15-30 minutes. Typically, visual recovery occurs in the first week following surgery and the eye may feel irritated for a day or so only. Medicated eye drops are prescribed for 1 week afterwards. There is usually little down time after LASIK and patients are able to participate in most activities with the exception of water sports for the first month.

The Key Advantages of LASIK Include:
Fast visual recovery.
Little postoperative discomfort.

The Disadvantages of LASIK Include:
Flap-related complications.
E.g. striae or folds, inflammation, epithelial ingrowth, retained debris and traumatic dislodgement.

Less Post Surgery Dry-Eye Discomfort
Reduced post-operative discomfort from dry eyes, as the majority of the upper corneal structure, remains untouched during treatment.

+What is Surface Ablation?

Surface ablation is a laser refractive procedure where the corneal epithelium is removed before laser ablation is applied to the underlying stroma in order to reshape the corneal surface. In myopia, the central corneal surface is flattened allowing the accurate re-focusing of light entering the eye. In hyperopia, the peripheral corneal surface is flattened instead. A period of 3 to 5 days after surface ablation surgery is needed for healing during which time pain or discomfort is usually experienced. A bandage contact lens is used to aid healing. Visual recovery takes weeks to months before refractive stability is achieved at about 3 to 6 months.

In general, surface ablation is performed on patients with either too thin or too steep corneas in order to preserve corneal strength. Occasionally, it is also performed on patients who participate in contact sports or on those who desire a flapless procedure.

The Advantages of Surface Ablation Include:
No flap related complications.
Tissue saving.
Good outcome for lower degrees of myopia and astigmatism.

The Disadvantages of Surface Ablation Include:
The post-surgical pain of 3 to 5 days.
Longer visual recovery.
Longer use of eye medications.
Increased risk of corneal haze (i.e. cornea scarring)
Slightly increased risk of corneal infections during the healing phase
Less predictable outcome for patients with higher corrections.
Photorefractive keratectomy, Laser-assisted subepithelial keratectomy (LASEK) and Epithelial Laser in Situ Keratomileusis (Epi-LASIK) are all surface ablation procedures and only differ in the method of epithelium removal. They all achieve equivalent visual acuity results.

+What is PRK?

Photorefractive keratectomy is a surface ablation method where the corneal epithelium is removed manually with a blunt instrument.

+What is LASEK?

LASEK (Laser-assisted subepithelial keratectomy) is a method of surface ablation where the corneal epithelium is removed with a dilute alcohol solution.

+What is Epi-LASIK?

Epi-LASIK (Epithelial Laser in Situ Keratomileusis) is a surface ablation technique where the surface epithelium is cleaved off using a blunt automated blade called an epitome.