A cataract is a clouding of the natural lens in the eye which leads to a decrease in vision. The cloudiness of the crystalline lens can occur at any age, from birth to elderly, depending on various factors. Age-related (senil) cataract is the most common type in practice which is also a common eye issue in older adults. It is the most common cause of vision loss in elderly people that can affect one or, mostly, both eyes.
Senil cataracts, in fact, can be considered an inevitable part of aging. Theoretically, if any person lives long enough he or she will eventually have cataract developed.
In adults, cataracts often develop slowly and painlessly, so vision and lifestyle can be affected without a person realizing it. As the time goes on, the gradual decline in vision (blurry vision), depending on the opacities in the crystalline lens, can not be properly corrected with glasses.
Cataract removal can be performed at any stage, depending of the individual needs of each patient, and no longer requires ripening of the lens. In fact, the fully ripened (mature) cataract has some drawbacks for actual surgical technique. On the other hand, surgery is not needed unless it causes problems and does affect the quality of life.
Cataract surgery is the most effective and most common procedure performed around the world by eye surgeons with a very high success rateç. It is usually performed as an outpatient basis using topical (anesthetic drops on the surface of the eye) anesthesia, with highly good results.
During cataract surgery, the natural opacified lens is removed and replaced with a clear artificial lens called an intraocular lens (IOL).
The most common type of actual cataract surgery is to break the opacified lens, by utilizing ultrasound energy, into particles small enough to aspirate through a small cannula through a narrow (1,8 to 2,4 mm) incision. This technique is called as ‘phacoemulsification’.
Once the cataract material has been removed a foldable tiny intraocular lens is then inserted through the main incision and positioned into the natural lens capsule left in place.
Nowadays, there are several pretty exciting choices of IOL’s to meet overall vision goals and lifestyle of the patient after cataract surgery and the choice of intraocular lenses is a popular issue which may confuse the patients’ mind.
All these new generation lenses are called as “smart or premium intraocular lenses” and the cataract surgery using these lenses as “premium cataract surgery”. These intraocular lenses have advanced features beyond ‘basic single vision’ that are not covered by standard intraocular lenses.
Actually, the most common type of lens used with cataract surgery is called a "monofocal" intraocular lens which has single focusing distance. Depending on patient’s needs and surgeon’s preference, it is set to focus for close or, mostly, distance vision. If it is set for distance vision, the wearing of eye glasses for reading or close work is needed or vice versa.
Today, presbyopia-correcting intraocular lenses are beginning to replace monofocal intraocular lenses because they allow correction at all distances, making vision as natural as possible. These lenses are produced in different zones set at different powers. Depending on design, the brain learns to select the right focus automatically in an adaptation period differing individually.
Nearly 90% of patients with multifocal intraocular lenses never need glasses again for any activities. Some patients need them only for very specific tasks.
Extended Depth of Focus (EDOF), or Extended Range of Vision, is a new technology in this area as Presbyopia-correcting IOLs. In contrast to multifocal intraocular lenses (IOLs), EDOF lenses work by creating a single elongated focal point to enhance “range of vision” or “depth of focus”.
Although most patients achieve spectacle independence with new generation multifocal IOL's and are satisfied with their final vision both far and near, some patients may have unsatisfactory outcomes. In these cases, brain adaptation may be too late or never.
In conclusion, the implantation of these intraocular lenses should be well discussed before operation and any patient with specific visual needs and any patient with very high visual expectations may not be a good candidate for these type of lenses.
An alternative to multifocal IOLs for correcting presbyopia is monovision. Monovision is the technique of fully correcting the refractive error of one eye and intentionally making the other eye mildly nearsighted. In this scenario, the fully corrected eye sees distant objects clearly and the mildly nearsighted eye sees very well up close without glasses.
Recently, the toric intraocular lenses are designed to correct the astigmatic refractive errors. The toric IOL is specifically designed to address those eyes which have a significant amount of astigmatism.
After cataract surgery, the postoperative recovery period is usually short. The patient is allowed to go home usually on the day of surgery. However, the cataract patients are advised to move cautiously and avoid straining or heavy lifting for about a month after surgery. The eye may or not be patched on the day of surgery and use of an eye shield at night is often suggested for several days.
Postoperatively, antibiotic and steroid drops are used for three to four weeks in tapering doses.