AGE RELATED MACULAR DEGENERATION (AMD)
AMBLYOPIA (Lazy Eye)
DIABETIC RETINAL EXAMINATION
INFANT VISION DEVELOPMENT
PRESBYOPIA (What is the need for reading glasses?)
VISION & COMPUTERS
AGE RELATED MACULAR DEGENERATION (AMD)
One million Canadians have some form of AMD, the leading cause of vision loss in Canada. More Canadians have AMD than breast cancer, prostate cancer, Parkinson’s or Alzheimer’s disease combined. AMD is a progressive condition that attacks central vision. People who have AMD may no longer be able to read, drive, or see the faces of
their family members. With an aging population, the number of people with the disease is expected to double in the next 25 years.
Prevention & Risk Factors:
There is currently no cure for either form of AMD, so prevention is important. The first step is to have your eyes examined in order to know if you have any of the signs of AMD, if you are at risk for developing AMD and we can teach you how be preventative.
Although researchers do not have a definitive cause for AMD, there are a number of factors that may put a person at greater risk for developing the disease.
- Family History
- Age is the greatest risk factor for AMD. An estimated one million Canadians have some form of AMD, and the majority of them are people over the age of 50. Prevalence increases the older you get.
- Gender, estrogen and early menopause – a higher incidence of AMD in women who experience earlier onset of menopause.
- Cigarette smoking – up to four times more likely to develop AMD compared to the general population, and people who smoke and have family history have 144 times the risk of the general population! Exposure to secondhand smoke also contributes to the risk of developing AMD, so if you quit, you’ll also reduce the risk of the people who are close to you.
- High blood pressure and Cardiovascular disease
- Overexposure in sunlight
- Wear sunglasses with a high UV rating
- Cover up with clothing and a hat
- Stay in the shade
- Sun exposure happens even on moderately bright or overcast days, or in the winter
- Diet may alter the risk of developing AMD
- A high consumption of linoleic acid, monounsaturated, polyunsaturated and vegetable fats is associated with double the risk of developing wet AMD
- Red Meat Intake Increases AMD Risk
- Those who ate two or more servings of fish that is high in Omega 3 fatty acids per week had a lower risk for developing AMD
- Other studies have shown that intake of fruits may reduce the risk of AMD, as would diets rich in carotenoids, such as lutein and zeaxanthin, found in dark green leafy vegetables and some berries.
Symptoms can include:
- Blurred or fuzzy vision: An early sign of AMD that, in some cases, might become less apparent under brighter lighting conditions.
- Straight lines appearing wavy or crooked: This symptom is particular to wet AMD and can affect both lines seen in near vision, such as sentences on a page, and those farther away, such as telephone poles and the sides of buildings.
- Decreased contrast sensitivity: People with AMD might have difficulty seeing objects that are the same color as their background, for example, black coffee in a black cup.
- A small, but growing, blind spot in the center of vision: Someone with AMD might be able to see the numbers on the circumference of a clock, but not the hands in the middle.
- Decreased ability to distinguish colors.
- Difficulty seeing at a distance.
AMD is classified into two types: dry AMD (also known as non-exudative) and wet AMD. Dry AMD is more common, accounting for about 90 per cent of AMD cases. It may cause little or no visual symptoms until it is more advanced. There is no cure for AMD, so early diagnosis is key. There are treatments available, but most of them stabilize vision at best. With later diagnosis, AMD treatments may be less effective, or fewer options may be available.
Dry AMD: Dry macular degeneration is diagnosed when yellowish spots called drusen begin to accumulate in the macula. Drusen are believed to be deposits or debris from deteriorating macular tissue. Gradual central vision loss may occur with dry AMD. Vision loss from this form of the disease is usually not as severe as that caused by wet AMD.
Intermediate AMD: People with intermediate AMD have, in one or both eyes, either many medium-sized drusen or one or more large drusen; in these people, there is usually little or no vision loss.
Wet AMD: Wet AMD is the more advanced and damaging stage of the disease. In about 10% of cases, dry AMD progresses to wet macular degeneration. With wet AMD, new blood vessels grow beneath the retina and leak blood and fluid. This leakage causes permanent damage to light-sensitive cells in the retina, causing blind spots or a total loss of central vision. The abnormal blood vessel growth in wet AMD is the body’s misguided attempt to create a new network of blood vessels to supply more nutrients and oxygen to the macula. But the process instead creates scarring and central vision loss.
If you are over 50 or have other risk factors for AMD, you need to be even more proactive about early diagnosis. And if you already have AMD, you still need to be alert to any further changes.
Technology for AMD In Our Office:
Digital Retinal Imaging: This test involves taking colour photographs of both the central and peripheral retina, which allows your eye doctor to document the extent and stage of AMD. These images can be compared between visits to follow the progression and/or improvement of the condition.
There is no cure for AMD, but severe vision loss is possibly preventable through the use of nutritional supplements, anti-VEGF treatments, laser surgery, and PDT.
Studies have shown that 25% of those with AMD can decrease their risk of developing advanced stages and vision loss by taking specific combination antioxidant vitamin supplements:
- Vitamin C
- Vitamin E
Vitamin supplements are not a cure for AMD and will not restore any lost vision. However, it has been shown that they can help maintain vision and slow the progression of the disease in some people. As preventative measures for those with very early stages of AMD, supplements have not been shown to be beneficial.
Some Other Beneficial Supplements:
- Folic acid
- Vitamins B6 & B12
- Fish oils
- Dark leafy greens & colorful fruits/vegetables (rich in lutein & zeaxanthin)
Ant-VEGF Treatments, Laser Surgery, and PDT:
If the macular degeneration becomes severe enough, your optometrist will refer you to a retinal specialist for further treatment.
Anti-VEGF injection is one of the most common ways of treating wet AMD. VEGF or vascular endothelial growth factor, is what causes the abnormal vascular growth underneath the retina in wet AMD. This injection targets and stops this specific chemical, to prevent further vessel growth and leakage and the progression of wet AMD.
Another treatment option of some forms of wet AMD is Laser surgery. This is a brief outpatient procedure that uses a focused beam of light to target the specific leaking blood vessel.
Photodynamic therapy (PDT) uses a combination of these treatment options, using a special drug and laser treatment to stop and slow the leaking blood vessels.
AMBLYOPIA (Lazy Eye)
Amblyopia is the lack of development of vision in one eye that is not directly caused by any eye health problem. It is not correctable with lenses alone. Amblyopia is the result of poor early development, and as such, occurs before the age of six. It is estimated that 2-4% of children under the age of six have Amblyopia.
Amblyopia results from a large difference in the prescription between the two eyes or it can occur when strabismus (crossed eyes) is present. It can also occur when something is interfering with the clarity of the various components of the eye. This causes blurred vision in the affected eye. Because the image that is sent to the brain from the affected eye is poor, the brain will ignore this eye. As the brain ignores the eye over time, very
few connections are made between the brain and the eye. It is this lack of connections between the brain and the eye that causes the eye to become amblyopic. This is why lenses alone cannot correct the problem.
Most of the time, there are no symptoms of Amblyopia. Since only one eye is affected, the other eye usually has reasonably good vision and tends to take over all visual tasks. Unless the good eye is covered, the person will rarely notice the poor vision in the amblyopic eye. Sometimes Amblyopia is associated with strabismus (crossed eyes),
which may be noted as a sign/symptom.
A comprehensive optometric examination can determine the presence of Amblyopia. The earlier it is diagnosed, the greater the chance for a complete recovery. That is why it is important to have your child’s vision examined at six months of age, again at age 3 and then regularly thereafter.
The most important part of Amblyopia therapy involves covering the good eye so that the brain is forced to recognize the amblyopic eye. This will lead to the development of more connections between the brain and the amblyopic eye and improve vision. This is most commonly done by placing a patch in front of the good eye. Patching the stronger eye is necessary to stimulate and strengthen the amblyopic eye. If patching is not tolerated well or is unsuccessful, then prescription eye drops are sometimes used in the good eye as a way to blur its vision temporarily. Corrective lenses may also be necessary.
An irregularly shaped cornea usually causes astigmatism. Instead of the cornea having a symmetrically round shape like a soccer ball, it is shaped more like a football where the curvature is greater in two directions.
In an eye with astigmatism, light fails to come to a single focus point on the retina to produce clear vision, instead multiple focus points occur. Either in front or behind the retina (or both). Astigmatism usually causes vision to be blurred or distorted to some degree at all distances.
Symptoms of uncorrected astigmatism are eyestrain and headaches, especially after reading or other prolonged visual tasks. Squinting also is a very common symptom of uncorrected astigmatism.
Astigmatism often occurs early in life, so it is important to schedule an eye exam for your child to avoid vision problems in school from uncorrected astigmatism. Astigmatism usually can be corrected with eyeglasses, toric contact lenses or refractive surgery. Focusing problems like astigmatism can be corrected with corrective lenses or refractive surgery.
When the normally clear lens within your eye becomes cloudy and opaque, it is called a cataract. Cataracts vary from extremely small areas of cloudiness to large opaque areas that cause a noticeable loss of vision.
Cataracts are most often found in persons over the age of 60, but they are also occasionally found in younger people, including newborns.
It is known that a chemical change occurs within your eye that causes the lens to become cloudy. This may be due to advancing age or it may be the result of heredity, an injury or a disease. Excessive exposure to ultraviolet radiation present in sunlight, cigarette smoking or the use of certain medications are also risk factors for the development of cataracts. Cataracts usually develop in both eyes, but often at different rates.
Currently, there is no proven method to prevent cataracts from forming. Wearing sunglasses is a tremendous benefit as they protect your lens from harmful UV rays, which can speed up cataract formation.
Cataracts develop without pain or redness, some indications that a cataract may be forming include blurred or hazy vision, the appearance of spots in front of the eyes, or the feeling of having a film over the eyes. A temporary improvement in near vision may also occur and increased sensitivity to glare, especially at night may be experienced.
A comprehensive eye examination by a Doctor of Optometry can determine if you have a cataract forming.
In the early stages of a cataract, where vision is only minimally affected, your optometrist can prescribe new lenses for your glasses to give you the sharpest vision possible. When the cataracts start to interfere with your daily activities and glasses cannot improve this vision, your optometrist will refer you to an eye surgeon who may recommend the surgical removal of the cataracts. The surgery is relatively uncomplicated and has a success rate of at least 95 percent.
Intraocular lens implants, inserted in your eye at the time of surgery, serve as a “new lens” and sometimes give you good distance vision without glasses. Your near vision may still be blurred. Your Doctor of Optometry can prescribe new lenses for your glasses about 4 weeks after surgery to maximize your distance and near vision.
DIABETIC RETINAL EXAMINATION
Everyone living with diabetes, whether type 1 or type 2, is at risk of developing diabetic retinopathy and vision loss. The risk increases the longer a person has diabetes and the more advanced it is. People with type 1 diabetes are more likely to experience vision loss sooner than those with type 2 diabetes. Early detection is key to preventing vision loss so have your eyes examined yearly.
Visual acuity test: The standard measurement of a person’s ability to see, using an eye chart.
Tonometry: A test that measures pressure inside the eye.
Biomicroscopy: Evaluate the front structures of the eye to determine if there are any signs of diabetes
Fundus photography: This test involves taking colour photographs of both the central and peripheral retina, which allows your eye doctor to document the extent and stage of your diabetic retinopathy. These images can be compared between visits to follow the progression and/or improvement of the condition.
- A high resolution image of the retina including the optic nerve, macula and the health of the blood vessels allowing for the confirmation of a healthy eye vs. detection of disease.
- A permanent record for your file, which allows us to view your images each year to look for changes.
- The opportunity for you to view and discuss the image of your eye with your doctor at the time of your exam.
Dilated eye exam: Drops are placed into the eye to widen the pupils to allow a direct
view of the inside of your eye, including the retina. A special magnifying lens is used to examine the retina and the optic nerve for signs of damage. This test may temporarily blur your vision for a couple of hours, so you will need to bring a driver. You will need to bring sunglasses to wear as your eyes will be sensitive to the sunlight.
The dilated fundus evaluation is covered by Alberta Health Care and can be done the same day as your comprehensive eye exam.
Farsightedness or hyperopia affects about ¼ of the North American population. Farsighted people may see things in the distance, but cannot see clearly up close.
This vision problem occurs when light rays entering the eye focus behind the retina, rather than directly on it. The eyeball of a farsighted person is shorter than normal. Farsighted people sometimes have headaches or eyestrain and may squint or feel fatigued when performing work at close range. This condition can be confused with presbyopia.
You may need to wear your glasses or contacts all the time or only when reading, working on a computer or doing other close-up work. Farsightedness can also be corrected with laser refractive surgery.
Glaucoma is an eye disease in which it is thought the internal pressure of your eye rises to a point that the optic nerve is damaged. The pressure that builds up is due to a problem in the production, flow or drainage of fluid normally produced in your eye. Glaucoma is one of the leading causes of blindness in Canada.
The exact cause of glaucoma is not known. For some reason, there is an overproduction of fluid and / or the passages that normally allow fluid within your eye to drain out become clogged or blocked. This results in fluid building up within your eye and increasing pressure on the optic nerve. The nerve fibers and blood vessels in the optic nerve can easily be damaged by this pressure. An injury, infection or tumor in or around the eye can also cause the pressure to rise.
Glaucoma most frequently occurs in individuals over the age of 40 and there is a hereditary tendency for the development of the disease in some families. Primary openangle glaucoma causes damage at an earlier age and leads to blindness at a much greater rate. There is also a greater risk of developing glaucoma when you have diabetes, high blood pressure and eye injuries. Regular optometric examinations are important for all ages to assess your risk for glaucoma.
A comprehensive ocular health examination is often the only way to detect glaucoma. Your optometrist can include in your examination a simple and painless procedure called tonometry, which measures the internal pressure of your eye. Your optometrist will also look into your eye to observe the health of the optic nerve and measure your field of
If diagnosed at an early stage, glaucoma can be controlled and little or no further vision loss should occur. If left untreated, side awareness (peripheral vision) and central vision will be destroyed and almost complete blindness may occur.
Treatment via eye drops and surgery is usually effective in maintaining your remaining vision. Once vision is lost due to glaucoma, it cannot be restored. This is why regular preventive eye exams are so important.
INFANT VISION DEVELOPMENT
The visual system of a newborn infant takes some time to develop. In the first week of life, your newborn’s vision is quite blurry, and they see only in shades of gray. It takes several months for your child’s vision to fully develop. Knowing the expected milestones of your baby’s vision development during their first year of life can insure your child is seeing properly and enjoying their world to the fullest.
NOTE:If you suspect something is seriously wrong with your baby’s eyes in their first few months of life (a bulging eye, a red eye, excess tearing, or a constant misalignment of the eyes, for example) bring your child in as soon as possible for an evaluation.
At birth, your baby sees only in shades of gray. Nerve cells in their eyes and brain that control vision aren’t fully developed. Also, their eyes don’t have the ability to change focus and see close object clearly. So don’t be concerned if your baby doesn’t seem to be focusing on objects right away, including your face. It just takes time. (Despite these limitations, studies show that within a few days after birth, infants prefer looking at an image of their mother’s face over anyone else’s.)
The First Month:
Color vision develops in the first few weeks Dilated eye exam life, so your baby is starting to see the world in full color. But visual acuity and eye teaming takes a bit longer — so if your infant’s eyes occasionally look unfocused or misaligned, monitor.
The eyes of infants are not as sensitive to visible light as adult eyes are, but they need protection from the sun’s harmful UV rays. Keep your baby’s eyes shaded outdoors with a brimmed cap and baby sunglasses.
Months 2 and 3:
Your baby’s vision is improving and their two eyes are beginning to move better as a team. They should be following moving objects at this stage, and starting to reach for things they see. Also, infants at this stage are learning how to shift their gaze from one object to another without having to move their head.
If your baby’s eyes are crossed or turning inwards it’s important to bring them in for an evaluation.
Months 4 to 6:
By 6 months of age, significant advances take place in the vision centers of the brain, allowing your infant to see more distinctly, move their eyes faster and more accurately, and have a better ability to follow moving objects with their eyes.
Visual acuity develops rapidly, improving from about 20/400 at birth to about 20/25 at six months of age. Your child’s color vision should be nearly fully developed at age six months as well, enabling them to see all the colors of the rainbow with ease.
Children also develop better eye-hand coordination at 4 to 6 months of age. They’re able to quickly locate and pick up objects, and accurately direct a bottle (and many other things) to their mouth.
We recommend having your baby’s eyes checked at six months of age!
Months 7 to 12:
Your child is now mobile, crawling about and covering more distances than you might have expected. They are also better at judging distances and more skilled at locating, grasping and throwing objects, too.
During months 7 to 12, your child is developing a better awareness of their overall body and learning how to coordinate their vision with their body movements. At this time, watch them closely to keep them from harm as they explore their environment. Keep cabinets that contain cleaning supplies locked, and put a barrier in front of stairwells.
The Alberta Association of Optometrists recommends you schedule your baby’s first eye exam when they are six months old. Though your baby can’t yet read letters on a wall chart, your optometrist can perform non-verbal testing to determine visual acuity, detect excessive or unequal amounts of nearsightedness, farsightedness and astigmatism, and evaluate eye teaming and alignment. We will also check the health of your baby’s eyes, looking for anything that might interfere with normal and continuing vision development. We welcome providing eye care for even the youngest children. For more information about eye exams for kids or to schedule your child’s first eye exam, please call our office.
Myopia, commonly known as nearsightedness, is the most common refractive error and has become more prevalent in recent years. The exact cause for this increase is unknown but has been linked to eye fatigue from prolonged computer use, other extended near vision tasks, and/or a genetic predisposition for myopia.
Nearsighted individuals have difficulty seeing distant objects clearly ex. Road signs, but are able to see well for close-up tasks such as reading. Signs and symptoms of myopia include squinting, eyestrain and headaches.
Myopia occurs when the eyeball is too long causing light rays to focus at a point in front of the retina, rather than directly on its surface. Nearsightedness can be corrected with glasses, contact lenses or refractive surgery. Depending on the degree of your myopia, you may need to wear your glasses or contact lenses all the time or only when you need clear distance vision ex. driving, seeing a chalkboard or watching a movie.
PRESBYOPIA (What is the need for reading glasses?)
Presbyopia, a focusing problem that develops in most people around the age of 40, occurs when people experience blurred near vision or a lag in focusing.
When people develop presbyopia, they find they need to hold books, magazines, newspapers, menus and other reading materials at arm’s length in order to focus their eyes properly.
They may also experience headaches, eyestrain or feel fatigued. Presbyopia is caused by an age-related thickening and a loss of flexibility of the lens inside the eye along with a loss of elasticity of the muscle fibers surrounding the lens.
Eyeglasses with bifocal or progressive addition lenses (PALs) are the most common correction for presbyopia. Other corrections include reading glasses, multifocal contact lenses, monovision contact lenses, and laser refractive procedures.
VISION & COMPUTERS
Most people who use a computer for prolonged periods ex. on the job, at school or at home including children may be at risk for computer vision syndrome (CVS), which is the use of a computer for many hours uninterrupted. Symptoms include: headaches, blurred vision, neck pain, redness in the eyes, fatigue, eye strain, dry eyes, irritated eyes,
double vision, and difficulty refocusing the eyes. These symptoms can worsen with improper lighting conditions (i.e. glare or bright overhead lighting or overhead vents, direct air from a fan.
Treatment includes: eyeglasses such as single vision computer glasses, bifocals or progressive additional lenses called task lenses specific to the computer. Taking frequent breaks is critical to reducing fatigue. The 20-20-20 Rule recommends getting up and moving away from your computer for short breaks at least every 20 minutes. Take a few
minutes to stretch your arms and back, and let your eyes relax their focus by looking at something at least 20 feet away. Blinking fully and frequently and the use of artificial tears will help to reduce dry eyes from computer use.