الفهرس 
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Abstract
Aim of the work
To study types, surgical techniques, complications and efficacy of different new types of Intraocular Lenses including:
1- Multifocal intraocular lenses.
2- Accommodating intraocular lenses.
3- Astigmatic intraocular lenses.
4- Phakic intraocular lenses.
Summary
Intraocular lenses are the artificial lens that replaces the eye’s natural crystalline lens. Intraocular lenses have been around since the mid 1960s. New designs have yielded improved visual outcomes, less complications, ability to restore accommodation and treat the pre-existing astigmatism.
Multifocal technology has already improved the quality of vision for many pseudophakic patients by reducing their need for spectacles. They produce simultaneous images using either diffractive or refractive optics. Thus providing excellent distance, intermediate and near vision. The limitations to this multifocal intraocular lens system are the presence of halos or glare around light at night and decreased contrast sensitivity.
Accommodating intraocular lenses are both the hope for and the wave of the future. Accommodating intraocular lenses function like the natural crystalline lens, there is a continuous range of vision instead of multiple individual focal points. They provide the near point add for the patient, therefore the subjective quality of vision is usually very good, free of the glare haloes.
The toric lens is a fixed-focus lens like a standard intraocular lens but it provides sharper unaided vision far away for those patients with pre-existing astigmatism before cataract surgery. Toric intraocular lenses are excellent complement to corneal astigmatic incisions and they are particularly useful for patients with very high amounts of keratometric cylinders. With these intraocular lenses we can correct a patients vision at more that one focal point. Toric intraocular lenses seem to be the next logical step in the quest for a plano post-operative result.
The implantation of phakic intraocular lenses has been shown to be an alternative for the correction of refractive errors. Several potential advantages have been described to the use of phakic intraocular lenses for the correction of refractive errors, including excellent refractive accuracy, preservation of accommodation, compatibility with procedures already established in cataract surgery and a phakic intraocular lens implantation, correction of higher levels of myopic refractive errors.