Presbyopic correction today

Presbyopia is the most common refractive error in patients older than 40 years. The loss of accommodation results in difficulty with near vision. Surgical means to correct this accommodative deficiency include scleral expansion band and anterior ciliary sclerotomy, which enhances the movement of the ciliary body. Monovision in which the non-dominant eye is left with some myopia for near vision can be done by presbyopic lens exchange or LASIK. Multifocal and accommodative intraocular lenses also require crystalline lens exchange. Conductive keratoplasty reshapes the cornea by using radiofrequency energy, and corneal inlays create a hyperpositive area of the cornea by implantation of a plus lens into the cornea or create a pinhole effect to increase the depth of field by implantation of a plate with a pinhole. Presby-LASIK creates a multifocal cornea by a combination of different ablation profiles, including central steep island and decentered steep island (center for near vision) and centered steep annulus (center for distance vision). Changing the asphericity of the cornea to increase the depth of focus (global optimum) is another approach for presby-LASIK.