Within the eye, there is a natural lens that focuses light, much like the glass lens in a camera. A cataract forms when the natural lens begins to cloud through the effects of ageing. By the 50s and 60s, there is more than a 50% chance that you will have some degree of cataract.
When mild, there will be few, if any, symptoms. But some degree of subtle visual loss can be measured, such as loss of contrast (the ability to perceive differences in shade between objects). This can cause difficulty in reading words if they are on a glossy page or, if the print is not dark enough. Glare or haloes/ rings around lights can also cause problems leading to loss in confidence driving at night or when driving into the sunrise or sunset.
As cataracts continue grow, there may be a noticeable reduction in vision when viewing both distant and near objects. Sometimes there is a shift to near sight, where viewing things up close become clearer but distant objects appear more blurry. Other times the opposite happens, distant objects become clearer but near objects less clear. Whatever happens, a continuing change is experienced and frequent changes in spectacle power are often recommended. As you would expect, a new pair of glasses will not always improve your vision back to its original level as glasses focus light but cannot improve vision through a cloudy cataract.
You may also have double vision when you look at things through the eye with the cataract. These problems can make it hard to read, work on a computer, and do anything else that calls for clear eyesight.
You may have poor night vision and find it harder to drive when it's dark. You may be sensitive to glare from headlights. People with advanced cataracts can even fail the vision part of a driver's test. Cataracts can make you more sensitive to glare from the sun. You might see a halo around bright lights. This can keep you from being outdoors as much as you'd like. It also makes it harder to play some sports, such as skiing or golf.
What can be done for cataracts?
When the changes described impact upon your lifestyle, removal of the cataract is the only permanent solution. There is no eye drop, laser or pill that will reverse cataracts. Fortunately, cataract surgery is quick, involves minimal down time and is highly successful.
If you have any of these symptoms, surgery could help. Sometimes you might need to get surgery even if your cataract doesn't bother you. Your doctor may suggest it if the cataract is large enough to crowd the inside of the eye, which can lead to increasing pressure in the eye. Before cataracts are removed, a full examination and a number of tests are necessary to ensure no other condition is responsible for the worsening of vision. Accurate measurements are also taken to eliminate or minimise the chance that spectacles need to be worn after the surgery.
Cataract surgery is usually performed one eye at a time. It is rare for surgery to be arranged on both eyes on the same day - there is rarely a pressing enough need for this and there is a theoretical risk of suffering the same complication in both eyes in simultaneous surgery, such as infection. However, because cataracts generally occur in both eyes simultaneously (although one eye may have a worse cataract than the other), surgery on your second eye may be arranged at the same preoperative clinic visit. Sometimes, surgery is arranged in both eyes (one eye after the other, about a week, a fortnight or a month apart), when required. Having your second cataract procedure soon after your first helps to ease the transition with spectacle requirements and can reduce the burden of uneven vision, which can impact daily activities (like driving) in between operations on each eye. This is particularly so if moderately severe cataracts are present in both eyes or, if you wear moderately powerful spectacle corrections.
During surgery, the cataract is removed through a small incision in a minimally invasive procedure. Once removed, an artificial intraocular lens or IOL is implanted in its place. In almost all cases, no stitches are required. A light sedative is given usually through an arm vein. It is day procedure not requiring an overnight admission and you can expect to be in hospital for 2-4 hours. Recovery of vision can take a day to several days, in most cases. Eye drops are prescribed for 4 weeks.
After cataract surgery, glasses are often no longer needed for distance vision but traditionally many people still need reading or near glasses or magnifiers. However, Multifocal IOLs are available which reduce and even eliminate the need for reading glasses. These can be very beneficial for people who do not wish to wear glasses anymore.