Effects of Multiple Optic Intraocular Lenses (IOLs) in After Cataract Surgery
When cataracts are surgically removed, replacement lens are put in place which can either be monofocal lenses or multifocal lenses. Aside from removal of clouded natural lens, cataract surgery can also correct or repair other vision problems such as astigmatism, presbyopia, nearsightedness, and farsightedness. Advanced replacement lenses or Intraocular Lenses (IOLs) used in modern cataract surgery are now capable of reducing or even permanently eliminating dependence on eye glasses or contact lenses.
The Difference Between Monofocal Lenses and Multifocal Lenses
Both monofocal lenses and multifocal lenses are considered Intraocular Lenses (IOLs). The difference between the two types can be observed in the effects in aspects of visual acuity, subjective visual satisfaction, eye glass or contact lens dependence after surgery, and contrast and glare sensitivity.
Considered as standard or traditional IOLs, monofocal lenses provides one vision or one point focus in far, immediate, and near vision. This means that point of focus is the same either in close-up or in distance. As such, the need to use glasses after surgery may arise.
Accommodating Multiple Optic Lenses or Multifocal IOLs are designed with more advanced features that allow good vision within a wide range of distances without the use of eye glasses or contact lenses. Near, intermediate, and distance vision is addressed with Multifocal IOLs creating good vision at all distances.
Effects of Multifocal IOLs
Multi Optic Intraocular Lenses (IOLs) or Multifocal IOLs provide various advantages and disadvantages in several aspects. On the overall expected good vision on after cataract surgery is most often met with this type of replacement lens. A few aspects with observed effects on various studies are as follows:
- On Visual Acuity and Spectacle Dependence – improved and unaided visual acuity for near vision is expected with Multi Optic IOL.
- On Glare and Contrast Sensitivity – studies have shown that people with multifocal replacement lenses are likely to see halos around lights and may experience reduced contrast sensitivity.
- On Subjective Visual Satisfaction – with Multi Optic IOL good vision is expected for far, immediate, and near vision. Its capability to provide good unaided vision at a range of distances provides a good after surgery experience and effects. In relation to contrast sensitivity on the other hand, the ability to distinguish objects against a background that is highly similar to the object being viewed may be affected at some degree and may affect overall good vision experience.
1 Surgery Options, Cataract Surgery, Decisions, Surgery Education Council, http: // eyesurgeryeducation .org / surgery – options – cataract – decisions . p h p
2 A Comparison of Multifocal and Monofocal Intraocular Lens Implants Used in Cataract Surgery, Cochrane Summaries, The Cochrane Library, D Calladine et al, September 12, 2012, http:// www .summaries . cochrane . org / CD 0 0 3 1 6 9 / a – comparison – of – multifocal – and – monofocal – intraocular – lens – implants – used – in – cataract – surgery