What is a Cataract?
A cataract is a clouding or discoloration of the normally clear lens of the eye. It can be compared to a window that is frosted, steamed or yellowed. There are many misconceptions about cataracts. It is not a film over the eye nor is it caused by overusing the eyes. It is not a cancer and does not spread from one eye to the other. It does not cause irreversible blindness. Symptoms related to cataract can include a painless blurring of vision associated with glare, halos, starbursts, light sensitivity and worsening of night vision. Patients frequently have to change their eyeglass prescription to avoid cataract surgery and on occasion can even notice double vision, or ghosted images in the involved eye. They frequently need brighter (more) light to read and have poor night vision. They may even complain of fading or yellowing of colors, and often times confuse black, brown, and navy blue colors in their wardrobe selection. The amount and pattern of this cloudiness varies within the lens itself. If the cloudiness is not to the center of the lens, you may not be aware that a cataract is present. The mere presence of a cataract does not mean it requires surgical intervention automatically. Surgery should only be done when patient lifestyles are altered because of the decline in vision related to the cataract. For example, one cannot see well enough to cook, read, drive, work or watch television (daily activities) despite the best prescription eyeglass or contact lenses possible. Typically this starts for most patients at the visual decline point of 20/40 or worse, best corrected. This is the typical visual and lifestyle standard recognized by Medicare and most insurance companies.
problems including diabetes (this can more rapidly speed up cataract formation) and inflammatory eye diseases (iritis, uveitis), past injury to the eye, and perhaps medications such as steroids (oral prednisone). Long term unprotected exposure to sunlight and previous intraocular eye surgery have all been implicated in the origin and progression of cataracts. The only way a cataract can be detected is by a thorough dilated eye examination by your ophthalmologist (medical eye doctor). He or she can detect the presence and extent of the cataract as well as any other condition that may be causing blurred vision or visual disturbances.
Cataracts develop differently in individuals and may even develop differently between the two eyes. Most cataracts are associated with ultraviolet exposure and the natural aging process and gradually get worse over a period of many years. Other cataracts, especially in younger people and those with diabetes, may progress rapidly over a few months causing a worsening of vision. It is not possible to accurately predict how fast cataracts will develop in any given patient, however there are certain types and diseases that we know accelerate cataract formation. Surgery is the only way your ophthalmologist can permanently remove a cataract, however, if symptoms from the cataract are mild, a change in glasses may be all that is needed for you to function more comfortably.
There are no medications, exercise, or optical devices that have been shown to prevent or cure cataracts. Recent studies have shown that daily protection from sunlight may help prevent or slow the progression of cataracts. Sunglasses that screen out ultraviolet light and regular glasses with a clear anti-UV coating offer this protection. Cataract surgery should be considered when cataracts cause enough loss of vision to interfere with daily activities. It is no longer true that cataracts need to be ripe before they can be removed. Cataract surgery can be performed when your visual needs (lifestyle) and declining visual acuity both require it. Many patients relate that it is like driving a car with a dirty windshield. You must decide if you can see to do your job and drive safely, or if you can read and watch TV in comfort and without difficulty. Also, if you can perform daily tasks such as cooking, shopping, yard work, and taking medications without visual difficulty.
Based on your symptoms, you and your ophthalmologist should decide together when surgery is appropriate. Over 1.4 million people have cataract surgery each year in the United States– 95% of these are without complication.
During cataract surgery, which is usually performed under local and sometimes topical anesthesia as an outpatient procedure, the cloudy lens is removed from the eye. In most cases, the focusing power of the natural lens is restored by replacing it with a permanent intraocular lens implant (IOL). Your ophthalmologist performs this delicate intraocular surgery using a surgical microscope, microsurgical techniques such as using an ultrasonic device that delicately breaks up the cataract into tiny pieces and then safely removes them from inside the eye, as well as other modern technology. A number of our cataract surgeons perform topical, clear corneal, no stitch cataract surgery techniques. While this approach is not possible or in the best interests of all patients, it is utilized at times as being a more advanced technique that allows for a more rapid visual recovery.
In approximately one-fifth of people having previously undergone successful cataract surgery, the natural capsule that supports the intraocular lens will eventually later become cloudy. Laser surgery is then used to open this cloudy capsule to restore clear vision. Following cataract surgery, you may return almost immediately to all but the most strenuous activities. You will have to take medicated eye drops as your ophthalmologist directs for several weeks, and wear a safety shield over your operative eye while sleeping for a brief period of time. Several post-operative visits are needed to check the progress of the eye as it heals.
Modern cataract surgery is a highly successful procedure. Improved vision results in over 95% of cases, exceptions being when there are other disease processes going on in the eye (glaucoma, macular degeneration). It is important to understand that complications can occur during and after surgery, some of which may be severe enough to limit vision. As with any surgery, 20/20 vision cannot be guaranteed, but the odds are greatly on your side of having a very good end result at the end of the process. In conclusion, cataracts are a common cause of poor vision, particularly in the elderly, but they are quite treatable. We can tell you whether cataract or some other additional problem is the cause of your loss of vision or visual disturbance, and can help you decide if cataract surgery is appropriate for you.
American Society of Cataract and Refractive Surgery
National Eye Institute