The most well-known part of a comprehensive eye exam is the basic vision test. When you have a general vision test, one of the main conditions the eye care practitioner is checking for is a refractive error. A refractive error means there is an abnormality in the shape of the eye, changing the eye’s ability to focus light directly onto the retina.This causes blurred vision and can usually be corrected by wearing prescription eyeglasses, contact lenses and possibly, alternate treatments such as vision therapy, ortho-k, LASIK or refractive surgery such as LASIK.

The term, “refractive error” refers to a problem with the process of refraction that is responsible for sight. Normally, light rays that enter your eye are refracted or bent through the cornea and the lens, and ultimately converge or are focused onto a single point on the retina. From the retina, messages are sent through the optic nerve to the brain which then interprets these signals into the image that we are seeing.   

In order for this process to work effectively, the anatomy of the eye including the length of the eye and the curvature of the cornea and the lens must be just right to be able to focus the light onto the retina. When this is not the case, a refractive error will occur.

There are several different types of refractive errors, depending on which part of the eye is affected, and it is possible to have multiple refractive errors at the same time:  

Myopia or nearsightedness:

In myopia the length of the eyeball is too long which results in light coming to a focus in front of the retina, rather than on the retina. This allows the individual to see well when objects are close but not clearly when looking at objects at a distance.

Hyperopia or farsightedness:

Hyperopia is when the eyeball is shorter than normal and can result in near objects being blurry. However, people experience hyperopia differently. Sometimes distant objects are clear while other times people may experience overall blurred vision near and far or no problems at all. In children particularly, the lens may accommodate for the error allowing for clear vision but may cause fatigue and sometimes crossed eyes or strabismus. Hyperopia causes eyestrain or fatigue especially when looking at near objects for a period of time. Often people with 20/20 vision may still need glasses at their desk to relax their eyes and improve concentration.

Astigmatism:

Astigmatism is usually the result of an irregularly shaped cornea (although it can sometimes also be due to a misshapen lens). The cornea, which is normally round, is more football-shaped in an eye with astigmatism, resulting in multiple focus points either in front of the retina or behind it (or both). People with astigmatism usually have blurred or distorted vision to some degree at all distances, near and far.

Presbyopia:

Presbyopia is an age-related condition which usually begins to appear sometime after 40.  As the eye begins to age, the lens stiffens and can no longer focus clearly on objects that are close.  

It’s important to note that presbyopia is often confused with hyperopia, as both cause problems focusing at near distances.  However, high hyperopia can also cause blur at far distances as well, especially in dim lighting, and depth perception problems can result in motor vehicle accidents.  In these instances people with hyperopia could use glasses at any distance.

If you are having trouble seeing, it is important to have an eye exam to determine the cause of the problem and to effectively correct your vision. Even if your vision is fine, you should schedule a routine eye exam on a regular basis to ensure that your eyes are healthy and that any potential problems are caught early.

‘Tis the season for giving, and parents, grandparents, family and friends need to know which toys and games to leave off the list because they can pose a risk to children’s health and eyesight. Last year nearly 252,000 emergency visits were due to toy-related injuries, almost half of which were to the head or face. Further, about 1 in 10 children’s eye injuries treated in the emergency room can be traced back to toys, most of which occur in children under 15 years of age.

The most common types of eye injuries that occur from toys can be anything from a scratch on the cornea (the front surface of the eye) to very serious injuries that can threaten vision such as traumatic cataracts, corneal ulcers, bleeding inside the eye and retinal detachment.

Most of these injuries can be prevented by taking the proper measures to evaluate the safety of gifts before they are purchased and to supervise children during any play with toys that could have the potential to cause damage or harm.

Here are some tips on how to select safe toys for children this holiday season:

1. Check age recommendations on all toys to make sure they are age appropriate and suitable for the child’s maturity level. If younger siblings are present, ensure that any toys made for older children are kept out of reach.
2. When possible, check toys for a seal of approval that the product meets national safety standards from a toy safety testing organization such as the American Society for Testing and Materials (ASTM) or the Canadian Toy Testing Council.
3. Do not purchase toys that have a projectile or sharp, protruding parts. Toys such as darts, guns, arrows or sharp propelling toys can cause serious eye injuries that can lead to permanent eye damage and even vision loss. Even high-powered water guns such as super soakers or soft foam dart guns can cause significant damage when shot at close range.
4. Purchase safety eyewear with polycarbonate lenses to accompany sports equipment, chemistry sets or woodworking tools. Speak to your optometrist to learn more about the best option for your child’s hobby of choice.
5. Check that toys with sticks or handles such as swords, fishing rods, pogo sticks, brooms or pony sticks have rounded edges or handles and avoid or supervise use with little children.
6. Any toys or devices that have a laser or bright light (such as laser pointers or flashlights which are sometimes used by kids to play laser tag) can be dangerous. Bright lights such as those produced by high-powered flashlights can cause temporary vision loss that can lead to a risk of a fall or accident. Further, laser pointers are not safe for use by children as the light intensity can cause permanent vision loss if shined in someone’s eyes.

When purchasing a toy for a child that is important to you, make sure you are considering what is most important – their safety. Ask us if you have any questions about the eye safety of a toy or gift you are considering.

Have you ever thought about how vision works? Seeing is an incredible gift made possible by a system in which the eye and the brain process visual information from the outside world. If any step of that process does not function properly, vision will be impaired.

Similar to a camera, the eye transmits light from the world around us into an image that we can perceive. Certain parts of the eye even function like the different parts of a camera such as the shutter, the lens and film (if we can hearken back to the days when we used film in cameras). Here is a quick breakdown of the fascinating way our eyes and brain enable us to see and experience the world around us:

The Vision Process

Light reflected from an object in our field of view is gathered by the cornea which is essentially the clear “window” to our eye. The cornea then refracts the light rays through the pupil (the center of the iris where light enters the eye). The iris, which like the shutter of a camera will enlarge and shrink based on how much light is coming in, then passes the image onto the crystalline lens. Just like a camera lens, the lens in the eye focuses the light rays, projecting them to a point at the back of the eye called the retina, where the image will appear upside down. The retina contains a thin layer of color-sensitive cells called rods and cones that perceive color.

From the retina, the visual signals travel to the brain via the optic nerve. The brain receives information from both eyes and must then converge the images (and flip them right side up) to get a complete picture.

Vision Problems

A breakdown in vision can happen at any point in this process. From the muscles that control the eyes, to the parts within the eye, to the pathway to the brain. Sometimes vision impairment is due to technical problems with the eye receiving the information and passing the signal on, such as convergence insufficiency (inability to coordinate the eyes to converge on one point), myopia (nearsightedness) or cataracts (clouding of the lens).

Other times, the eyes might work perfectly, but there is a problem with the brain interpreting the signals it receives. In these cases we can’t “see” in the traditional sense, because our brains aren’t able to properly “read’ the signals or we don’t know what we are looking at. This is the case for some learning disorders that are caused by the visual processes in the brain such as dyslexia.

As you can see, vision is quite a complicated process. A simple vision exam isn’t always able to determine vision problems, especially in children which is why it is so important to have regular comprehensive eye exams, to measure the health of the eye and all of its parts.

Eye Complications of Diabetes

It’s true. Diabetics have a higher risk of blindness than those without the disease. That fact coupled with the superior prognosis of early intervention, makes it easy to understand why optometrists and doctors say routine eye care is absolutely essential. Below, we’ll discuss what your eye doctor is looking for during a diabetic eye exam.  

As the incidence of diabetes increases, it is important to spread awareness about the risks and proper preventative care for diabetes patients. November is Diabetes Awareness month, so read on!

Diabetics are at greater risk of for a number of eye problems.  

Diabetic Retinopathy:

Diabetic retinopathy is the term used for the disorders associated with diabetes that cause progressive damage to the retina.  The longer a patient has had diabetes, the more likely it is that he will develop these conditions which can be very serious, vision-threatening complications. 

There are two types of retinopathy: nonproliferative and proliferative. 

Nonproliferative retinopathy, which is the most common form, is when capillaries at the back of the eye become weakened and may start to leak blood and fluids. Nonproliferative retinopathy, which often has no symptoms, can be characterized as mild, moderate or severe, depending on how many blood vessels are affected and becoming blocked. This type of retinopathy usually doesn’t require treatment and doesn’t cause vision loss, unless the leaking fluid ends up in the macula where the eye focuses – a condition called macular edema. If this happens, vision can be blurred and even lost so preventative treatment is essential.  

Proliferative retinopathy is much more severe. This is when so much damage is done to the blood vessels that they begin to close off. New blood vessels begin to grow in the retina as a response to this deterioration. The new and weak vessels can leak blood, impairing vision, or can form scar tissue which can distort the retina or cause a retinal detachment.

Proliferative retinopathy requires urgent referral to an ophthalmologist for treatment. While it usually takes years to develop, some instances of proliferative retinopathy can occur within weeks or months if blood sugars are not well-controlled. Pregnancy can also accelerate proliferative retinopathy in known diabetics. Yet if detected early, treatment can be done successfully. 

Like high blood pressure, there are often no warning symptoms until advanced stages of diabetes. It is best to get checked each year by an optometrist. If you experience any changes in your vision such as spots in vision, flashes of light, blurred or double vision (rarely pain), make an appointment with your eye doctor immediately. Treatments do exists for retinopathy and many of them are successful in repairing damage and sometimes even restoring vision.

Cataracts: 

Cataracts are a clouding of the lens of the eye which blocks light from entering and impairs vision. While cataracts are a fairly common and treatable condition, people with diabetes are 60% more likely to develop the condition and often get them at a younger age. Those with the condition also may experience vision fluctuation which occurs from sugar levels affecting the lens of the eye. Cataracts often progress faster in diabetics as well. In serious cases of cataracts, a surgical procedure is done to remove the natural lens of the eye which can sometimes cause complications in diabetic patients that may already have symptoms of other conditions such as diabetic retinopathy.

Glaucoma:

Glaucoma is a serious condition where pressure builds up in the eye causing damage to the retina and optic nerve and eventually if left untreated, blindness.  Diabetics are 40% more likely to develop glaucoma and the risk increases with age and the amount of time the individual has had diabetes. There are treatments for glaucoma including medications and surgery but early detection and treatment are essential to prevent permanent vision loss. Glaucoma is often called the “silent thief of sight” because vision loss often doesn’t occur until significant damage is done. Therefore, yearly eye exams are essential. 

Cornea Alterations:

Diabetics may experience reduced sensitivity in their cornea. This means that contact lens wearers that are diabetics should be more cautious, as they develop higher tolerance if the lens irritates the eyes and may be at greater risk of infection. 

Eye Muscle Disturbance:

More advanced diabetes cases can show restriction of eye muscle movement due to nerve palsy. 

For diabetics, the key to early detection and treatment – and therefore preserving your vision – is to have your eye health monitored on a regular basis. Get your eyes examined every year by an optometrist and if you experience any changes in your vision such as spots, floaters, blurred vision or pain, make an appointment with your eye doctor immediately. 

Beware this Halloween and think before you blink (in decorative contact lenses that is)! Sure, decorative contact lenses can enhance any Halloween costume, but if not taken seriously, they can also cost you your vision. Whether they are sold as cosmetic lenses, colored lenses or fashion lenses, they are anything but cosmetics – they are medical devices that must be approved by the FDA and properly fit and handled. Stores selling decorative lenses without requiring a prescription are breaking the law.

All contact lenses must be properly fitted by an eye doctor that has measured your eye and given you proper handling and care instructions.  A poor fit can result in serious eye damage, corneal scratches, infections, vision loss and even blindness. 

When purchased and handled properly, decorative lenses can be a fun (or spooky) addition to your costume, so go ahead and purchase them, but do it safely. 

Here is the right way to buy decorative lenses:

• Get a contact lens eye exam and fitting from a licensed eye doctor and a valid prescription for contact lenses that includes the lens measurements, brand, base curve, diameter, power and color as well as an examination date and an expiration date. When the lens is coming from a legitimate source, the lens supplier ensures it has not expired and that manufacturer takes care of the material and tracking bar codes. 
• Optimally, have your optometrist order the lenses or if that is not possible, purchase lenses from a registered store or online shop that requires you to provide this prescription to ensure that it is properly fit.
• Follow the directions for cleaning, storing and wearing lenses.
• See your eye doctor immediately if you experience persistent redness, pain or vision disturbances.
• Important note: Many patients believe that a routine eye exam and eye glasses prescription is the same as a contact lens prescription but this is not the case! Many online companies do not advise people of the difference or do not adhere to the one year prescription expiry. This is a big concern for eye doctors because eye health changes can detrimentally affect contact lens wear. All contact lenses should be checked yearly by an eye doctor or registered contact lens fitter. 

Contact us today to book a contact lens exam.

The home can be a dangerous place if you aren’t aware of the risks that surround you. This is specifically true for your eyes and vision. Nearly half of all serious eye injuries take place in or around the home and the majority of these can be prevented with proper awareness and precaution. Whether you are cooking, cleaning, tending to yard work or doing home repairs, it is important to be aware of the possible dangers to your eyes and to take preventative measures to protect them.

It is recommended that every household have at least one pair of protective eyewear on hand to use during activities, projects or tasks that could pose a danger to your eyes. While protective eyewear can reduce your risk of an eye injury by 90%, in fact, only 35% of North Americans wear protective eyewear during tasks that could be dangerous to their eyes. Such activities could include the following:

Use of dangerous or hazardous chemicals: Many substances, such as cleaning chemicals, are hazardous and can be the cause of serious eye injuries and burns upon contact. In fact, household cleaning products like bleach cause 125,000 eye injuries a year.

Proximity to flying debris: Particularly when working in the yard mowing, trimming, shoveling and clipping, debris and particles can be thrown into the air that can enter your eye. This goes for those actually doing the gardening as well as bystanders.

Using sharp tools: Whether you are dealing with shovels and clippers, or hammers, nails and screws, it is important to protect your eyes. Many eye injuries are caused by the actual tools which are mishandled, dropped or used carelessly.

Projectiles: Flying objects pose a serious danger to the eyes, particularly with power tools, nails and screws. Never use power tools without protective eyewear. 

When it comes to selecting protective eyewear there are certain requirements that the Occupational Safety and Health Administration (OSHA) has established to ensure your safety. Our eyewear experts are happy to help you find the best eye protection for you and your family.

Bottom line: use common sense and be EyeSmart, especially if there are children around for whom you’re setting an example.

Over the centuries there have been a lot of old-wives tales circulating about eyes and vision. You know, like the one that if someone hits you on the back while your eyes are crossed they will stay that way. Unlike this example, some of these myths do have roots in truth, yet filtering out those truths isn’t an easy task.

Here are a few of the most common myths and truths about the eyes and vision.

1. Myth: Eating a lot of carrots will help you see in the dark.

   Truth: Carrots have a lot of Vitamin A, a vitamin that is essential for good eyesight, but eating a lot of carrots isn’t going to give you 20/20 vision or help you see in the dark. Likely, the basis of this over-exaggeration is that night-blindness and vision loss found in underdeveloped countries can be a sign of malnutrition due to Vitamin A deficiency. However, you only need a relatively small amount of Vitamin A for vision, and it is easily obtainable in a normal balanced diet from a lot of sources, not limited to carrots. 

   Higher-than-normal doses of Vitamin A might be useful in treating certain eye conditions and as part of a combination of vitamins used to slow the progression of early-stage macular degeneration. However, in any of these cases, do not take Vitamin A supplements without instructions from your eye doctor.

2. Myth: Wearing glasses makes your vision worse.
   
   Truth: People think this is true because often once we start wearing glasses our vision continues to deteriorate and we have to keep going back for a higher prescription. The notion that wearing glasses causes your vision to get worse is simply not true. Distance vision or myopia typically gets worse over time, especially during childhood and adolescence, and does depend on whether the child wears glasses. Additionally, most people begin to experience vision deterioration as they enter their 40’s and 50’s with or without the use of vision correction devices.
3. Myth: Sitting too close to the TV is bad for your eyes.
   
   Truth: While it may cause your eyes to feel tired, there is no evidence that sitting too close to the TV will harm your eyes or vision. Children in fact have a heightened ability to focus on close objects so often it is natural and relatively comfortable for them to sit close to a screen.
4. Myth: Reading in dim light can damage your eyes.
   
   Truth: This one also has no good evidence. While yes, your eyes are working harder and may feel tired when reading in dim light, there is no evidence of permanent or long-term damage to your eyes.
5. Myth: As you get older there is nothing you can do to prevent vision loss.
   
   Truth: While most older adults will eventually develop some degree of presbyopia which is near-vision loss, and eventually cataracts, no sign of vision loss should be ignored. Vision problems like these can be treated, allowing you to see clearly again. Moreover, there are many serious eye diseases such as glaucoma and macular degeneration that can threaten your vision and eyes with permanent and severe vision loss if not diagnosed and treated early. If you are 40 or older, you should have your eyes checked with a comprehensive eye exam on a yearly basis. In many cases, early treatment can save your eyesight.
6. Myth: Squinting causes vision loss.
   
   Truth: Squinting is a natural reaction of your eyes to let less light into the pupil in order to sharpen your focus. Rather than impairing your vision, squinting is usually a sign that someone can’t see clearly which often suggests that their vision is impaired and that they need glasses to see better in the first place.

Got any other eye myths that you are curious about? Just ask at your next visit to our office. We are happy to help weed out the fact from the fiction.