Artificial lens (artifice)

Pseudophakia is the presence of an artificial lens in the eye. An eye with an artificial lens is called pseudophakic.

Intraocular correction of aphakia has a number of advantages over glasses. It is more physiological, eliminates patients' dependence on glasses, does not narrow the field of vision, peripheral scotomas, or distort objects. An image of normal size is formed on the retina.

There are currently many designs of artificial lenses. According to the principle of attachment in the eye, there are three main types of artificial lenses:

• Anterior chamber lenses are placed in the anterior chamber of the eye and find support in the angle of the anterior chamber. They contact very sensitive tissues of the eye - the iris and cornea. These lenses provoke the formation of synechiae in the angle of the anterior chamber of the eye, which explains their rare use at present;
• pupillary lenses (pupillary) are also called iris-clip lenses (ICL). They are inserted into the pupil according to the clip principle, these lenses are held by anterior and posterior support (haptic) elements. The first lens of this type - the Fedorov-Zakharov lens - has 3 posterior arches and 3 anterior antennae. In the 60-70s of the 20th century, when intracapsular cataract extraction was mainly used, the Fedorov-Zakharov lens was widely used throughout the world. Its main disadvantage is the possibility of dislocation of the support elements or the entire lens;
• posterior chamber lenses

(ZKL) are placed in the lens bag after removal of the nucleus and cortical masses during extracapsular cataract extraction. They take the place of the natural lens in the overall complex optical system of the eye, therefore providing the highest quality of vision. ZKLs strengthen the dividing barrier between the anterior and posterior sections of the eye better than others, prevent the development of many severe postoperative complications, such as secondary glaucoma, retinal detachment, etc. They contact only the lens capsule, which does not have nerves and vessels, and is not capable of an inflammatory reaction. This type of lens is currently preferred. Among the ZKLs, posterior capsular ones can be distinguished, which are attached directly to the capsule. They are used in cases where, after a previous injury, the transparent lens bag has not been preserved, but only a compacted cloudy posterior capsule remains, fused with the remains of the anterior.

The artificial lens is made of hard (polymethyl methacrylate, leucosapphire, etc.) and soft (silicone, hydrogel, polyurethane methacrylate, collagen copolymer, etc.) materials. They can be multifocal or made in the form of a prism.

Two artificial lenses can be inserted into one eye at once. If for some reason the optics of the pseudophakic eye are incompatible with the optics of the other eye, then it is supplemented with another artificial lens of the required diopter.

The technology for producing artificial lenses is constantly being improved, and lens designs are changing as required by modern cataract surgery.

Correction of aphakia can also be performed using other surgical methods based on enhancing the refractive power of the cornea.

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