CHAPTER 1

The Science of Refractive Surgery

The goal of refractive surgery is to reduce dependence on contact lenses or spectacles for use in routine daily activities. A wide variety of surgical techniques and technologies are available, and all require an appropriate presurgical evaluation to determine the best technique and ensure the optimal outcome for each patient individually.

Refractive surgical procedures can be categorized broadly as corneal or intraocular (Table 1-1). Keratorefractive (corneal) procedures include incisional, laser ablation, lamellar implantation, corneal collagen shrinkage, and collagen crosslinking techniques. Intraocular refractive procedures include phakic intraocular lens (PIOL) implantation and cataract surgery or refractive lens exchange (RLE) with implantation of a monofocal, toric, multifocal, or accommodative intraocular lens. Each technique has advantages and disadvantages and should be specifically matched to the individual patient.

Table 1-1

This chapter reviews the fundamental corneal properties relevant to refractive surgery (focusing