Search results
Results from the WOW.Com Content Network
A corrective lens is a transmissive optical device that is worn on the eye to improve visual perception. The most common use is to treat refractive errors: myopia, hypermetropia, astigmatism, and presbyopia. Glasses or "spectacles" are worn on the face a short distance in front of the eye.
An Intraocular lens ( IOL) is a lens implanted in the eye usually as part of a treatment for cataracts or for correcting other vision problems such as short sightedness and long sightedness; a form of refractive surgery. If the natural lens is left in the eye, the IOL is known as phakic, otherwise it is a pseudophakic lens (or false lens).
Cataract surgery may be performed to correct vision problems on both eyes. If both eyes are suitable, people are usually advised to consider monovision. This procedure involves inserting an IOL providing near vision into one eye, while using one that provides distance vision for the other eye.
Intraocular lenses that correct presbyopia are divided into two main categories: Multifocal IOLs: achieve near and distance vision by having two (bifocal) or three (trifocal) focal points simultaneously. The function of multifocal IOL depends on the pupil size for refractive types.
Intraocular lenses that are implanted into eyes after the eye's natural lens has been removed during cataract surgery are known as pseudophakic. Phakic intraocular lenses are indicated for patients with high refractive errors when the usual laser options for surgical correction ( LASIK and PRK) are contraindicated.
The development of IOLs was considered a notable innovation, as patients previously had to wear very thick glasses, or a special type of contact lens, in order to cope with the removal of their natural lens. IOLs can be used to correct other vision problems, such as toric lenses for correcting astigmatism.
D018918. [ edit on Wikidata] Phacoemulsification is a cataract surgery method in which the internal lens of the eye which has developed a cataract is emulsified with the tip of an ultrasonic handpiece and aspirated from the eye. Aspirated fluids are replaced with irrigation of balanced salt solution to maintain the volume of the anterior ...
Complications after cataract surgery are relatively uncommon. Posterior vitreous detachment (PVD) may occur but does not directly threaten vision. Some people develop a posterior capsular opacification (PCO), also called an after-cataract. This may compromise visual acuity, and can usually be safely and painlessly corrected using a laser.
The newest type of intervention is a type of PIOL called the implantable collamer lens ( ICL) which uses a biocompatible flexible lens which can be inserted in the eye via a 3 mm incision. The ICL is used to correct myopia ranging from −0.5 to −18 diopters, and +0.5 cylinder power to +6.0 for the Toric ICL models.
Aphakia can be corrected by wearing glasses or contact lenses, by artificial lens implantation, or by refractive corneal surgeries. Eyes with artificial lenses are described as "pseudophakic". Etymology. From Ancient Greek a-, privative prefix + phakós, lentil, anything shaped like a lentil, e.g. a lens, via New Latin. References