Lens implants are prosthetic devices embedded in the human eye following surgical removal of the eye's natural lens due to the presence of cataracts. Generally referred to as intraocular lenses, or IOLs, these synthetic implants cause marked improvements in the visual acuity of cataract patients, states the American Academy of Ophthalmology's EyeSmart.
IOLs are broadly classified into two types: mono-focal and multi-focal. Mono-focal IOLs can be optimized for near, intermediate or distant vision. Patients who typically opt for this type of IOL further require the use of eyeglasses or contact lenses for some tasks.
Multi-focal IOLs, meanwhile, are designed for both near and distant vision. However, certain factors may influence the effectiveness of this type of IOL, such as the patient's pupil size and history of other visual problems, notes EyeSmart.