Q) I have been told that I have cataracts. Do I have to go for surgery now or can I wait until all the pandemic related hassles that come with visiting a hospital die down?
A) Cataracts are a condition marked by the clouding of one or both of the eye’s lens. The lens works to bend (refract) light that has entered into the eye onto the retina (the tissue at the back of the eye with special cells called photoreceptors) which transmits that light into electrical signals which the brain then interprets into what we call vision.
A cataract begins when proteins in the eye form clumps. They develop very gradually over time. Eventually these clumps prevent the lens from sending all of the light clearly to the retina resulting in distorted vision. Cataracts are incredibly common.
According to the National Eye Institute in the United States, by age 80 half of us will either have a cataract or will have already undergone cataract surgery. In their early stages, cataracts do not tend to affect your life very much. Like many medical conditions, many of us may have them and not even know it. However, in this case, this is not concerning because cataracts do not pose a threat to your health. As such, delaying your surgery to a more suitable time in your life is not an issue at all. Your vision will continue to slowly deteriorate but there are no other downsides.
Over time, cataracts can start to impact your life by making routine tasks such as reading or driving more difficult. Symptoms of a cataracts include:
· Blurry or cloudy vision
· Poor night vision
· Light from headlights, the sun or household lights appearing to be too bright
· Colours appear to be faded
· Double vision
· Halos appear around lights
· Your eyeglasses no longer are strong enough
There are seven different types of cataracts that are classified by either –
a) How they were caused eg: traumatic (caused by force) and congenital (you are born with) or
b) Their location within the lens eg: nuclear and cortical cataracts
Most cataracts are caused by normal processes that occur within your eye. At around age 40, proteins within the eye start to breakdown and subsequently clump together. There are however other possible causes as well. These include the long-term use of certain medications such as corticosteroids (prednisone), smoking, radiation therapy, exposure of the eyes to ultraviolet radiation from the sun, trauma or a secondary result to certain diseases such as diabetes.
Should cataracts progress to the point that they are impacting your life, surgery is the normal remedy but in some cases the changes in vision can be managed by other measures such as getting new glasses or contact lenses, using brighter lights at home or work, wearing anti-glare sunglasses or a magnifying glass for tasks like reading.
Many do eventually choose surgery because it has a very high success rate (about 90% can see better immediately afterwards) and is considered a low-risk procedure. With surgery, an artificial intra-ocular lens (IOL) is placed where the natural lens was. There are several different types of IOL’s that all come with distinct pros and cons.
Mono-focal lenses are designed to provide excellent vision, but only for one type, either near or far vision. Most people who choose this type of lens have their IOL set for distance and then use reading glasses for up close tasks.
Some people will choose to use a replacement lens for distance vision in their dominant eye and in a later operation have a close vision lens inserted into the other eye. Over time, the brain synchronizes the input from each eye into an ability to see both near and far. Some people can stop wearing glasses altogether although many (approximately 75%) will still need them for certain tasks, in particular for night driving.
This procedure does take a period of adjustment although the transition should be easier for those who have used contact lenses that use the same approach in correcting vision. Less than 5% who undergo this procedure will experience visual disturbances like seeing streaks, shadows or halos. These often improve within the first three months but a small number of people will require another surgery to replace one or both lenses.
Multifocal IOLs have multiple corrective zones built into the lens, akin to bifocals or trifocals. This allows both eyes to see both near and far vision and in some cases they may also correct for intermediate vision as well. Accommodative type lenses have flexible arms called “haptics” that use the movements of the eye’s muscles to change focus from distance to near. As such they can correct vision at all distances.
Multifocal and accommodative lenses may increase your chances of being able to forgo wearing glasses (in one study, 70% were able to see without them) but they also increase the likelihood you may have side effects such as glare and halos. Other types of lenses that can be chosen are extended depth-of-focus IOLs which have only one corrective zone which is stretched to allow both distance and intermediate vision and toric lenses which have a built-in correction for astigmatism.
IOLs are meant to last a lifetime so the choice of which lens to go with is important and requires consultation with your eye specialist. Factors that need to be considered are your lifestyle, whether you drive frequently at night, any other eye disorders you might have (such as glaucoma or age-related macular degeneration) as well as costs since OHIP does not pay for some of the newer innovations in cataract surgery. For more information about this or any other health related questions, contact your pharmacist.