What is the cornea, and what does it do?

Despite its clear appearance, the cornea is actually a highly organized tissue comprised of five layers that, unlike most other bodily tissues, has no blood vessels whatsoever – it is protected and nourished instead by the tears, and by the fluid that lies behind it. The cornea, in turn, protects the eye from damaging UV rays, particles of dirt, and invasive germs that could harm it. It also focuses light onto the retina, which is then translated into electrical impulses that ultimately lead to image perception. The cornea is basically the eye’s camera lens, putting things into proper focus so the retina can produce vision.

What can go wrong with the cornea?

Unfortunately, corneal tissue is delicate and susceptible to several common problems. The cornea has strong healing powers that allow it to quickly repair itself after sustaining minor injuries, but a deeper injury can cause scarring, which can result in:

• Blurred, impaired vision
• Eye pain
• Sensitivity to light
• Eye redness and inflammation
• Chronic headaches and fatigue
• Nausea and disorientation when focusing

Disease is also a major factor affecting the cornea. The most common corneal disease is keratoconus, a progressive thinning of the cornea that, rather than occurring with age, is most prevalent in teenagers and young adults. Keratoconus causes the cornea to curve and bulge abnormally, leading to blurred vision, nearsightedness, astigmatism, and increased light sensitivity. Optometrists use a slit lamp exam and to diagnose keratoconus. Distorted vision resulting from keratoconus can usually be corrected with glasses or contacts.

Other corneal diseases include various corneal dystrophies, tissue growths and shingles. Current treatments for ocular problems are conducted with lasers or conventional surgery, but research offers hope for a better tomorrow for those with corneal damage.

Corneal research by the U.S. National Eye Institute

Researchers at the NEI are currently conducting studies into wound healing of the cornea, which could lead to new treatments and improved outcomes for corneal transplants and grafts. Because the need for donor corneal tissue habitually outstrips supply, research is being done into more refined artificial corneas that are engineered in the lab and can actually be injected into the eye, as opposed to making a larger surgical incision. Research is also being done into a procedure that uses low doses of UV light to strengthen the collagen bonds of the cornea, promoting faster wound healing. To learn more about the specific types of research being conducted into corneal health, visit the National Eye Institute here.

One essential element of eye health is to maintain a regular schedule of visits to your eye care professional. If you do not already have a family optometrist in Toronto, Toronto Eye Care would be pleased to step into that role to assess the health of your corneas and ensure optimum eye care at all ages and stages.

Supplements that may support the aging eye

As we age, our risk of developing age-related macular degeneration (AMD) increases. Fortunately, along with conventional treatments, certain inexpensive vitamins have also been identified that can slow down the process of macular degeneration: The AREDS vitamins, so named after the studies that obtained and refined the research data around these nutrients. AREDS vitamins contain antioxidants and other nutrients that can help stave off the aging process for the eyes – at much higher doses than those found in an ordinary multivitamin. There are two versions of the AREDS vitamins: the original, which contains

• 500 milligrams of vitamin C
• 400 International Units of vitamin E
• 15 milligrams of beta-carotene (or 25,000 International Units of vitamin A)
• 80 milligrams of zinc as zinc oxide
• 2 milligrams of copper as cupric oxide (copper is necessary to prevent copper deficiency anemia, which could occur as a result of consuming high levels of zinc)

And the AREDS 2 formula, which was developed later and contains all of the above except the beta-carotene – which, because it can increase the chances of developing lung cancer in high doses, was contraindicated for smokers – and also adds 10 milligrams of lutein and 2 milligrams of the eye-healthy antioxidant zeaxanthin.

It’s important to note that no evidence exists to suggest that taking AREDS vitamins will actually prevent the onset of AMD; it has been shown to slow the disease progression and severity in people who already have the disease.

Supplementation for other eye conditions

Apart from AMD, where most of the studies have been focused, there is little evidence that taking supplements can help with specific eye conditions or prevent them from developing in the first place. One supplement that may help people with dry eyes is Omega-3, the fatty acids found in oils from coldwater fish like salmon (and other marine sources, such as shrimp and krill). These long-chain fatty acids are closely linked to proper eye development in utero and correct cell function. However, eye doctors like Richard Gans, MD usually recommend that patients obtain Omega-3s and antioxidants from food sources wherever possible, which provide the best bioavailability and absorption because of the other nutrients they also contain. Eating at least two servings of coldwater fish like sardines, salmon, halibut and herring each week is said to provide sufficient Omega-3s.

Your bottom line on supplements and eye health

If you are eating a diet that you already know is very low in lutein, Omega-3s or certain vitamins such as Vitamin A, which is important for retinal health – or if you have been diagnosed with age-related macular degeneration already – supplements may be a good idea; but despite the widespread availability of such vitamin formulas, you should to speak with an optometrist first before embarking on a new course of supplements. Depending on your health history and other factors, a dietary change, rather than supplementation, may be indicated.

Not sure whether the vitamins you’re currently taking are doing anything for your eyes? Book an appointment to discuss nutrition with an eye specialist at one of our downtown Toronto optometrist locations.

Eye floaters: Fast Facts

What exactly are eye floaters, and where do they come from?

• Eye floaters are also known as vitreous floaters and ‘flying flies’ because they float within the jelly-like vitreous humour that lies between the optic lens and the retina.
• The ability (or curse!) to see eye floaters is known as myodesopsia.
• Some people are born with floaters and they will usually have them for life.
• As we age, the once-transparent vitreous humour begins to develop imperfections and accumulate build-up in the form of minute particles. Vitreous humour cells can also begin to clump together in the aging process.
• It is these imperfections, clumps and tiny external objects that cause shadows to be projected onto the retina, where you see them as floaters.
• Floaters are considered both common and benign. Most people learn to live with floaters, or the floaters eventually go away on their own.

When floaters become severe

The Mayo Clinic states that it’s rare for eye floaters to cause serious vision impairment, however, it does happen. If floaters are causing problems in your life, it’s important to book an appointment for an optometrist visit right away, because sudden onset of floaters could be indicative of a serious condition such as a retinal tear or posterior vitreous detachment (PVD).

While floaters are often easily observed by an optometrist with the use of simple diagnostic tools like an ophthalmoscope or slit lamp, floaters may sometimes be difficult to observe depending on what position they’re in – even if the patient complains of their severity. That’s why a thorough examination by a specialist as opposed to a GP, is necessary.

Treatment options for floaters

Unfortunately, there are as of yet no medications or eye drops that will make floaters disappear. Currently, there are two recognized treatment options for severe floaters: surgery and laser techniques. Both are generally used only in the worst cases, as there are considerable risks involved. In the case of surgery, the vitreous humour is surgically removed and replaced with saline solution – but this may not permanently eradicate all floaters, and as well, there is a risk of intraocular bleeding, cataracts, and retinal tears.

With laser surgery, performed by an ophthalmologist, a laser is used to break up larger floaters so they become less noticeable. Not very frequently used, this surgery has the risk of human error if the laser is not aimed with sufficient accuracy, as well as conditions such as retinal detachment or macular edema.

While researchers continue to look into the problem of eye floaters and attempt to develop more effective solutions, it’s recommended not to be alarmed if you occasionally see a tiny floater or two; your brain will eventually learn to ignore them. If floaters have become a concern, please visit the Toronto Eye Care clinic for a comprehensive assessment to rule out more serious causes of the floaters you are seeing.

No one likes to have red eyes.

Whether caused by fatigue from an overnight flight, allergies, or captured in a photo due to a camera’s improper exposure, if we have red eye, we want to get rid of it!

When the whites of our eyes are red or bloodshot, we don’t look or feel our best.

Red eye is caused by dilated blood vessels on the surface of the eye. If enough blood vessels are present, bringing extra blood into the eye, it can give the entire surface of the eyes a pinkish or reddish cast.

These blood vessels can appear for a number of reasons:

• Infections, like pinkeye
• Allergies
• Inflammation
• Pressure building up inside the eye, such as that caused by sudden glaucoma

If you suffer from red eyes and are tired of others guessing at the reason, read on to find out more about red eyes and how to defeat them.

Symptoms of Red Eyes

When your eyes are red, that’s probably not the only symptom.

Most people also feel itchiness in their eyes or the feeling that there is something ‘in there’ even when a thorough mirror search reveals nothing. It may feel like rubbing your eyes is imperative to relieve the itching, stinging sensation.

Other symptoms that tend to go with red eyes include:

• Tearing up
• Pain and soreness
• Sensitivity to light
• Symptoms elsewhere in the body, like cold and flu symptoms, nausea or vomiting

It’s important not to think of the degree of redness as being indicative of how serious the problem is.

Usually, red eyes do not indicate a serious problem and the redness should go away on its own. But whether your eyes are completely bloodshot or not, the two indicators you should not ignore are accompanying eye pain and vision problems.

If your eyes actually hurt (as opposed to being itchy or feeling dry) and if your vision is actually impaired at any point, that is when you should take red eyes very seriously and seek medical attention.

Common Causes of Red Eyes

Eye redness is no fun, but as mentioned, it is often nothing more serious than common pinkeye – clinically known as infectious conjunctivitis – or an allergic reaction that has caused inflammation.

Thinking of the moments prior to your eye redness…

Did you touch an animal, plant, flower or fibrous material, and then touch your eyes?

Have you been exposed to dust through cleaning, or pollen from newly budding trees?

If you have come into contact with these things or any other known allergens, try taking an antihistamine and resting your eyes for 30 minutes.

Eye pain can also indicate a foreign body in the eye or a corneal scratch. Rubbing the eyes vigorously can make these conditions worse and even cause permanent damage to the eyes.

Red eyes can, in rare cases, also indicate more serious types of infections or corneal ulcers.

If you are experiencing pain rather than simple irritation, and/or other symptoms like seeing halos, experiencing nausea or vomiting, or a rash over and above just having red eyes, please visit our optometrist clinic in Toronto right away for an advanced diagnostic test that will get to the bottom of what’s causing your red eye.

Telescope technology for incredibly precise results

Wavefront LASIK uses cutting edge laser vision technology to deliver a result that is as unique as your own eyes are. Using incredible technology adapted from the same kind that allows the Hubble Telescope to take such laser sharp images, Custom Wavefront LASIK uses light to take 3-D measurements of the eye to create a precise map of its contours. This allows the lasers to reshape the surface of the cornea according to this precise map, correcting vision according to the person’s actual needs rather than according to a standard template.

Features of the Wavefront procedure

Wavefront LASIK is considered to be a very safe procedure and it’s one that is being practiced more and more by surgeons who are willing to invest in the latest equipment and techniques. Some features of the Wavefront procedure include:

• Measures your eye’s ability to focus light rays from the inside out to ensure that any irregularities or imperfections, not just the more common ones, can be properly corrected
• Uses a computer guided laser programmed by the surgeon, as opposed to a manual technique
• Improves not only vision as measured by the eye chart, but actual vision outcomes.

It’s interesting to note that ‘perfect vision’ really does seem to be in the eye of the beholder. After standard LASIK, while some patients have perfect 20/20 vision, they still report issues with glare and halos, especially at night. Custom Wavefront LASIK seems to reduce these negative outcomes because it is able to treat the less common refractive errors – that is, in addition to treating myopia (nearsightedness), hyperopia (far-sightedness) and astigmatism, like conventional LASIK does, Custom Wavefront LASIK also treats other less-common irregularities that can lead to post-surgical problems such as decreased ability to see contrasting details and poor night vision. Custom Wavefront corrects all abnormalities in the cornea, leading to generally better outcomes for patients.

Is Wavefront LASIK right for you?

Wavefront technology has been around for over a decade now, yet it still hasn’t completely supplanted conventional LASIK, despite the improved outcomes. The reason is that Wavefront LASIK removes more corneal tissue than does traditional LASIK, so patients who have already had eye surgery or have naturally thin corneas may not be able to choose Wavefront. The same goes for patients at the extreme high end of the prescription range. As with all laser eye surgery, to qualify, your eyes must be healthy and without any complications such as dry eye.

If you’re considering laser eye surgery, let your journey begin at Toronto Eye Care. Our doctors only recommend the most trusted and competent laser eye surgeons in Toronto. We have built strategic and longstanding relationships with the leading laser surgery centres in the city – Bochner Eye Institute, Crystal Clear Vision and TLC Laser Eye Centres, whose experienced surgeons have facilitated thousands of successful laser eye procedures through our clinics.

Take your first step by scheduling a consultation with your Toronto Eye Care doctor to discuss your vision goals.

Eyeglass prescriptions are standardized worldwide

That’s great news if you find yourself stranded on vacation with damaged glasses – we recommend that you always carry a copy of your most current prescription in your wallet, so local opticians will be able to craft a new pair for you if necessary.

An eyeglass prescription can contain several different numbers – no wonder it’s confusing. For a person whose prescription is -4.50                   -0.75      x 90, here is what those numbers mean:

• The -4.50 describes the spherical refractive error, which is either farsightedness or nearsightedness. Because there is a negative sign in front of the 4.50, that means the person is nearsighted (quite nearsighted actually!). A plus sign would mean they are farsighted.
• This second number, -0.75, indicates the person has an astigmatism, which is a distortion in the shape of the cornea that causes blurred vision. Not everyone has astigmatism, of course, so if the number wasn’t there, you’d see some letters – DS or SPH – to indicate that there is no astigmatism.
• The last number relates back to the astigmatism. Because astigmatism causes the lens to be football- or somewhat cone-shaped as opposed to perfectly rounded, it is measured in degrees; in this case, the astigmatism has a 90-degree orientation.

Additional numbers and letters in an eyeglass prescription

We’ve just described what the numbers can look like for three of the most common types of refractive errors. However, some people have additional abnormalities that must be corrected to achieve perfect vision. These may be indicated by the following:

-An additional number followed by a symbol, such as 2^, indicates prism correction. Each eye can have several prism numbers depending on the prescription

-Near reading strength numbers for people requiring bifocals for reading. These numbers usually stay relatively low, beginning at +0.75 and ending around +3.00.

Finally, you may be wondering what OD and OS mean. OD refers to the right eye and OS means the left eye; if you have an identical prescription in both eyes, you might see the letters OU.

Confused after your regular eye exam?

If you usually leave the eye doctor wondering about elements of the prescription or unsure as to what vision care options are open to you, it might be time to get a second opinion. Toronto Eye Care offers comprehensive eye exams carried out by caring and experienced eye doctors, ophthalmic technicians and assistants. Each eye examination is customized depending on your age group, medical/visual history, and personal risk factors. We’ll get to the bottom of what is causing your vision concerns and provide accurate correction so you can see clearly again. Call to book your appointment today.

Understanding your eyeglass prescription

After your eye exam, the doctor hands you a small slip of paper covered with confusing numbers. You take it, without even looking at it, straight to your optician, who uses it to make your next pair of lenses. At no time do you understand any part of the process. Sound familiar? While you don’t really need to understand your eye prescription, in the sense that you don’t really need to understand how electricity works in order to use it…it’s definitely good to know what is going on with your eyes so you can track any changes, spot any mistakes, and understand what your prescription means to your day to day vision. Here, we’ll demystify the eyeglass prescription so you can finally know for sure what the numbers mean.

Eyeglass prescriptions are standardized worldwide

That’s great news if you find yourself stranded on vacation with damaged glasses – we recommend that you always carry a copy of your most current prescription in your wallet, so local opticians will be able to craft a new pair for you if necessary.

An eyeglass prescription can contain several different numbers – no wonder it’s confusing. For a person whose prescription is -4.50                   -0.75      x 90, here is what those numbers mean:

• The -4.50 describes the spherical refractive error, which is either farsightedness or nearsightedness. Because there is a negative sign in front of the 4.50, that means the person is nearsighted (quite nearsighted actually!). A plus sign would mean they are farsighted.
• This second number, -0.75, indicates the person has an astigmatism, which is a distortion in the shape of the cornea that causes blurred vision. Not everyone has astigmatism, of course, so if the number wasn’t there, you’d see some letters – DS or SPH – to indicate that there is no astigmatism.
• The last number relates back to the astigmatism. Because astigmatism causes the lens to be football- or somewhat cone-shaped as opposed to perfectly rounded, it is measured in degrees; in this case, the astigmatism has a 90-degree orientation.

Additional numbers and letters in an eyeglass prescription

We’ve just described what the numbers can look like for three of the most common types of refractive errors. However, some people have additional abnormalities that must be corrected to achieve perfect vision. These may be indicated by the following:

-An additional number followed by a symbol, such as 2^, indicates prism correction. Each eye can have several prism numbers depending on the prescription

-Near reading strength numbers for people requiring bifocals for reading. These numbers usually stay relatively low, beginning at +0.75 and ending around +3.00.

Finally, you may be wondering what OD and OS mean. OD refers to the right eye and OS means the left eye; if you have an identical prescription in both eyes, you might see the letters OU.

Confused after your regular eye exam?

If you usually leave the eye doctor wondering about elements of the prescription or unsure as to what vision care options are open to you, it might be time to get a second opinion. Toronto Eye Care offers comprehensive eye exams carried out by caring and experienced eye doctors, ophthalmic technicians and assistants. Each eye examination is customized depending on your age group, medical/visual history, and personal risk factors. We’ll get to the bottom of what is causing your vision concerns and provide accurate correction so you can see clearly again. Call to book your appointment today.

Why might I need prisms?

Sometimes, people who don’t necessarily have an underlying refractive error have eyes that tend to pull apart when they are called upon to focus. While this used to be colloquially known as ‘lazy eye’ or ‘wandering eye’, it is actually a condition wherein one eye wants to be dominant rather than working in concert with the other eye. Whether the submissive eye wanders up, down, to the left or to the right, it’s caused by a muscular imbalance; the dominant eye has become stronger while the other cannot stay focused on the task at hand. This muscular imbalance is known as a fixation disparity.

Where prisms come in to help relieve the symptoms of the imbalance is not so much by focusing the less dominant eye, but by tricking the brain into thinking both eyes are working together. Other than laser eye surgery, which can sometimes correct the need for prisms (but not always), prisms provide the most reliable relief from a fixation disparity. Sometimes the condition can be corrected by wearing contact lenses, but not all people who need prisms are good candidates for contacts.

How do prisms work?

Prisms work in eyeglasses by bending light in order to trick the brain into thinking that both eyes are focused on the same thing. This reduces eyestrain and doubled vision by aligning the two images properly so that people with a fixation disparity see things as they are, rather than as they look to two separately focused eyes. Prisms do the same job in eyeglasses that decorative ones do in windows: bend ordinary while light. In glasses, the prisms bend and bounce light in such a way that it effectively makes the eyes think they are pulling together.

A comprehensive eye exam can detect whether prisms are right for you

Among the many types of ocular and medical tests performed at Toronto Eye Care are tests to determine whether or not your vision is properly aligned. If it’s not, prisms can help bring your vision back into alignment and reduce your discomfort levels when reading and doing close work. In addition to binocular vision testing to determine whether you are seeing blurry or double, you can also expect a full diagnostic workup of tests that include:

• Refractive tests to determine degree of nearsightedness/farsightedness
• Corneal curvature and thickness tests to determine astigmatism and suitability for laser eye surgery
• Retinal scan to detect holes, tears and detachments
• Tests for diseases such as glaucoma and AMD
• Colour vision testing

And, of course, after the eye exam, you will not only receive a current eyeglass/contact lens prescription that can be filled at our convenient onsite dispensary, but also counselling, treatment and referrals to experts if necessary, who can provide a further medical plan of action.

If you’re wondering whether your problems focusing indicate a need for prisms, schedule an eye exam for professional advice.

What are toric lenses?

In order to understand what makes toric lenses different, it’s important to first understand what astigmatism is and how it affects the eye. Astigmatism is not an eye disease, but is one of the refractive errors of the eye preventing light rays from bending correctly for proper focus. It’s caused by a deviation, usually in the cornea, from the typical spherical shape that the cornea normally takes; instead of being symmetrically round, the cornea is more cone or football-shaped. Many people with the condition may simply assume that their blurred or distorted vision is just part of their near-sighted or far-sighted prescription but astigmatism is actually another error which compounds their visual dysfunction.

A toric contact lens is a custom designed and shaped to conform to the eye and correct the astigmatism. Its unique shape creates different light-refracting powers on the vertical and horizontal planes of the lens to accommodate the differently-shaped cornea of patients with astigmatism, and thus properly correct the person’s vision. Simply increasing the power of your regular contact lens to correct the astigmatism is generally ineffective and a potential source of even greater eye strain.

How to find the right toric contact lenses for you

The experienced optometrists at Toronto Eye Care are toric contact lens experts and will help you choose the appropriate contact lenses that are the right power and fit for your eyes. Our specialized contact lens examinations will also advise you on the proper insertion, removal and care techniques to ensure optimal performance. Yes, this process involves more effort than clicking online but specialized contact lenses require professional care and attention.

If you suspect that your current contact lenses are underperforming, or if you have an astigmatism and are considering going from glasses to contacts, consult with one of our eye doctors for professional care that makes a difference. To book your personalized consultation, call us or send an email to contactlenses@torontoeyecare.com.

Our Eye Doctors can provide early detection of eye diseases like AMD

For patients who have spent a lifetime in glasses or contact lenses, changes to vision are sometimes dismissed; is it just the relentless progression of myopia, or perhaps a worsening astigmatism that’s making everything blurry? Accepting changes in vision as we age, without taking action, can be dangerous because vision loss could be symptomatic of a condition like age-related macular degeneration. A visit to Toronto Eye Care can discern the true reasons behind the vision loss. Our experienced eye doctors will perform a variety of diagnostic tests to confirm diagnosis and then recommend a customized treatment plan to reduce your risk of progression.

5 ways a optometrist can assist macular degeneration patients

The ‘dry’ form of macular degeneration has treatment options which include lifestyle changes and evidence based supplements.The more serious form or ‘wet’ AMD – has seen significant advances in new clinical treatments Here are some of the ways your we can help if you have already been diagnosed with AMD.

1. Monitor Disease Progression

Depending on pigment abnormalities in the retina and the number and size of drusen (tiny white spots under the retina) your optometrist can note the progression of the disease and estimate its trajectory, and help you plan for the future.

2. Refer to a Retina Specialist When Necessary

If patients progress to WetAMD then a referral to a retina specialist is necessary to administer eye injections that block the growth of abnormal blood vessels in the eye . As eye care leaders in downtown Toronto since 1993, we work closely with a network of the best retina specialists located in all the major hospitals.

3. Optimized Eyeglasses Prescription

Patients with AMD can often benefit from stronger prescription eyeglasses, especially for reading fine print.

4. Dry AMD Age Related Eye Disease Study Vitamin Supplements

Studies suggest it may be possible to slow the advancement of the ‘dry’ form of the disease by taking the AREDS 2 formulation (vitamin C, vitamin E, lutein, zinc and zeaxanthin). For more information, please book an appointment with one of our doctors.

5. Lifestyle Changes

Studies suggest that following a certain type of diet that includes plenty of dark leafy greens, fish and colorful fruits and vegetables, and not much saturated fat or processed foods is also good for eye health. Other lifestyle adjustments will include lowering cholesterol, maintaining a healthy body weight, protecting the eyes from harmful UV rays, and not smoking.

If you have concerns about your vision and whether you are doing all you can to protect it, please book an appointment with our clinic today.