A cataract is a dense, cloudy area that forms in the lens of the eye. A cataract begins when proteins in the eye form clumps that prevent the lens from sending clear images to the retina. The retina works by converting the light that comes through the lens into signals. It sends the signals to the optic nerve, which carries them to the brain.
It develops slowly and eventually interferes with your vision. You might end up with cataracts in both eyes, but they usually don’t form at the same time. Cataracts are common in older people.
Common symptoms of cataracts include :
There are several underlying causes of cataracts. These include:
There are different types of cataracts. They’re classified based on where and how they develop in your eye.
Risk factors associated with cataracts include :
Your doctor will perform a comprehensive eye exam to check for cataracts and to assess your vision. This will include an eye chart test to check your vision at different distances and tonometry to measure your eye pressure.
The most common tonometry test uses a painless puff of air to flatten your cornea and test your eye pressure. Your doctor will also put drops in your eyes to make your pupils bigger. This makes it easier to check the optic nerve and retina at the back of your eye for damage.
Other tests your doctor might perform include checking your sensitivity to glare and your perception of colors.
Cataract cannot be corrected with glasses or medication. Surgery is the definitive treatment. Various surgical options are available depending on the severity of cataract and patient’s lifestyle.
In cataract surgery the cloudy lens is removed from the patients lens bag and replaced with an artificial one. At RNH Hospital, we perform cataract surgery by taking a microunioun (2mm) and phacoemulsifying the nucleus .it is an incredibly delicate procedure requiring lots of skill.Modern day cataract surgery is evolving from a visual restorative to a refractive procedure.
There are numerous types of IOL (Intraocular lens) option that we use to replace the original one.
Intraocular lenses (IOLs) are medical devices that are implanted inside the eye to replace the eye's natural lens when it is removed during cataract surgery. IOLs also are used for a type of vision correction surgery called refractive lens exchange.
Before the use of intraocular lenses, if you had cataracts removed, you had to wear very thick eyeglasses or special contact lenses in order to see clearly after cataract surgery, since no device was implanted in the eye to replace the focusing power of the natural lens.
Today there is a wide variety of premium IOLs to choose from. The best intraocular lens for you depends on many factors, including your lifestyle and your specific visual needs.
The following is an overview of premium IOLs currently used. These are considered "premium" intraocular lenses because they have advanced features beyond those found in basic single vision IOLs.
During your preoperative exam and consultation, your cataract surgeon can help you choose the best IOL for your needs.
Toric IOLs are premium intraocular lenses that correct astigmatism as well as nearsightedness or farsightedness.
The most suitable patient is the one who strongly desires not to wear glasses after having eliminated medical contra-indications and exposed side eff ects especially halos.
Patients with significant night activity should be avoided as halos at night may disturb patients especially when driving.
These halos disappear for 20% of patients during the first month and for 40% of patients during the first year presumably by a Neuro-adaptation phenomenon.
They persist to varying degrees for the remaining 40% without significant reduction in activities.
An orthoptic assessment will be done to eliminate any microtropia. Analysis of the cornea must be scrupulous and any disease of the tear film must be treated beforehand because meibomian gland dysfunction can greatly disturb patients postoperatively.
New apodized diffractive IOLs being pupil-dependent, photopic (Scheimpflug data) and mesopic (Colvard Pupillometer) measurement of the pupil will avoid narrow photopic or over dilated scotopic pupils.
Limits of 2mm in photopic and 5 mm in scotopic will avoid any pupillary refractive disorder postoperatively.
Astigmatism management is of paramount importance for obtaining ideal postoperative results with MFIOLs. A postoperative astigmatic error exceeding three-quarters of a diopter results in significant decline in visual quality.
A residual astigmatism lower than 0.50D does not seem to impair visual acuity, but we systematically treat astigmatism with toric lens if possible with the goal of no residual astigmatism.
Corneal limbal incisions could be performing to treat lower astigmatism.
Pathological capsular bags or capsular bags at risk because of uncontrolled healing should be avoided in order to prevent any decentration of these IOLs.
Finally a macular OCT analysis is performed when there is a doubt at fund us examination in order to eliminate an incipient macular traction syndrome or Epiretinal Membrane (ERM)
Accommodation, a property of the young crystalline lens allows focus for both distance and near vision. This is generally lost as the person ages or following cataract surgery wherein the natural lens is replaced with a monofocal intraocular lens. Presbyopia-correcting intraocular lenses (IOLs) including MFIOLs provide spectacle independence for both near and distance vision.
Three general optic principles have been applied to provide multifocality in the present day IOLs: multizonal refractive, diffractive, and extended range of vision (EROV) designs.
It seems to us that sub 2mm micro incision (CMICS or BMICS) should be the rule in order to prevent any astigmatism induced by the incision and the risk to increase high order aberrations.
If topical anesthesia is becoming increasingly popular, we have chosen since 2012 to systematically perform sub-Tenon anesthesia to avoid any discomfort during the procedure.
The second eye is operated on 2 to 5 days after the first one to eliminate any trouble due to an eventual anisometropia.
Surgery to remove a cataract is generally very safe and has a high success rate. Most people can go home the same day as their surgery.
Cataracts can interfere with daily activities and lead to blindness when left untreated. Although some stop growing, they don’t get smaller on their own. The surgical removal of cataracts is a very common procedure and is highly effective roughly 90 percent of the time, according to the National Eye Institute.
To reduce your risk of developing cataracts:
Cataracts can cause significant changes in vision. Cataracts occur not only in older adults, but in younger people, too. Injury, certain medications, and genetic conditions can result in cataracts, even in the very young.
It should be noted that not all vision changes are the result of cataract. Several of the above symptoms can be signs of very serious and life-threatening conditions. See an eye doctor to discuss your vision changes and any other symptoms you may be experiencing.