Four types of operations done here
A 2006 study by the Ministry of Health lists these types of Lasik procedures done in Singapore:

Standard Lasik
A microkeratome (knife) is used to make a hinged flap in the cornea. Tissue is then removed based on the patient's refraction (the ability of the eye to refract light that enters it to form an image on the retina) prior to the operation.

Wavefront-guided Lasik with microkeratome flap
A wavefront evaluation is first used to assess the entire optical characteristics of the eye before treatment is customised to the eye. The flap is made with a knife. Wavefront-guided Lasik is a new technology that provides an advanced method of measuring optical distortions in the eye.

Bladeless Lasik without wavefront evaluation
Corneal flap is made with a laser, instead of a knife. Corneal tissue is removed depending on the pre-operative refractive error.

Wavefront-guided Lasik with bladeless flap
A wavefront evaluation is first used to assess the entire optical characteristics of the eye before treatment is customised to the eye. Corneal flap is made with a laser (bladeless).

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