[Presbyopia--the last major challenge in ocular surgery].

Presbyopia is the natural loss of accommodation that affects the majority of middle-aged individuals. Once a person reaches their mid 40s, has trouble making activities that were easily performed when younger such as reading, using a cellular phone or computer. In addition to the visual difficulties emotional repercussions have been observed. The mechanism of presbyopia is not completely understood but it has many treatments from monovision and refractive surgery to scleral expansion surgery or PreLEX. Presbyopia represents one of the major challenges facing ophthalmology today.