Synchrony dual optic accommodating lens dating game show 1970

The multifactorial basis for the development of presbyopia makes it difficult to be managed adequately.The aging population, especially in western countries, has created millions of candidates around the world for such interventions.

Synchrony dual optic accommodating lens

Approximately, 1 mm of movement is equivalent to almost a 2 D power change.

These lenses are known as “positional pseudoaccommodative IOLs”, and their visual results in terms of providing partial or total near visual acuity restoration in the long term have been disappointing.

This concept refers to any other method that changes the power of the whole optical system of the eye or changes partly the way in which it works in order to relieve patients for near distance vision.

Nevertheless, pseudoaccommodation is not a real restoration of accommodation [The theory of accommodation is largely based on Helmholz's ideas: the capsule has sufficient elasticity to mold the lens into a more strongly curved system than what is necessary for distance vision.

Almost all surgical techniques that have been proposed to date for the surgical correction of presbyopia are based on the acquirement of pseudoaccommodation [].

Pseudoaccommodation comprises a group of techniques that can improve near vision on the basis of the use of the cornea or intraocular lenses (IOLs), resulting in an increased depth of field, multifocality or both [].

Until currently, virtually all surgical techniques that have been proposed for its correction are based on the induction of pseudoaccommodation in the presbyopic eye, including multifocality.

However, the real restoration of accommodation is more complex, and it has been tried by the use of different, so called, “accommodative” pseudophakic intraocular lenses (AIOL).

However, none of them could achieve a complete restoration of accommodation, and multifocal lenses are frequently associated to visual symptoms that may decrease patient satisfaction.

Therefore, presbyopic surgery is one of the most difficult targets that a refractive surgeon will have to deal with today and in the immediate years.

Abundant research is still necessary in order to answer this question, but we could at the very least learn from past mistakes, which gave rise to some clear some concepts [The majority of AIOLs that have been proposed are not really accommodative lenses as their mechanism of action is based on changing the axial position of a monofocal IOL in relation with the cornea, hence changing the global eye power.

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