Orthokeratology
Introduction Orthokeratology is a widely accepted optical treatment for myopia control in children, especially in East Asian countries. However, this treatment has existed for many years, originally having been introduced…
Crosslinking Instrumentation
Introduction The clinical success of crosslinking was made possible by the development of ultraviolet (UV)-light emitting diodes (LEDs) that allowed for a reasonable balance of cost and performance with reliable…
Photorefractive Keratectomy
Introduction The excimer laser revolutionized the world of vision correction because of its precision and unique abilities to reshape the corneal surface. This laser can remove scars and other opacities…
LASEK and Epi-LASIK
Introduction Definition and Terminology Laser subepithelial keratomileusis (LASEK) combines certain elements of both laser in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK). In LASEK—instead of completely removing the epithelium, as…
Patient Evaluation for Refractive Surgery
Introduction As refractive surgery has evolved from the controversial to the routine, more patients want to decrease their dependence on glasses. Laser in situ keratomileusis (LASIK) is a very common…
LASIK and TopoLink for Irregular Astigmatism
Introduction Decentration of the ablation and other factors have contributed to inducing irregular astigmatism in a certain number of eyes treated with laser refractive surgery. Topography-guided ablations present a surgical…
Preoperative Evaluation of Keratoconus and Ectasia
Introduction In the last 2 decades, the clinician’s ability to diagnose keratoconus has increased. This is due to the knowledge and development of diagnostic instruments for keratoconus, from corneal topography…
Optical Coherence Tomography in Refractive Surgery
Introduction Anterior segment optical coherence tomography (OCT) has been incorporated into clinical practice in refractive surgery to customize preoperative selection and to improve postoperative evaluation and follow-up. Instruments The first…
Excimer Lasers
Introduction The possibility of using the excimer laser for the cornea was first raised in the early 1980s. Using Munnerlyn’s equation, which established a relationship between the change in refractive…
Laser and Mechanical Microkeratomes
Introduction Unlike methods of surface photoablation, the laser in situ keratomileusis (LASIK) technique requires a superficial corneal flap to be created prior to photoablation with an excimer laser. Mechanical microkeratomes…
