Accommodation is the lens inside the eye working to bring vision into focus. Esotropia is the excess turning of an eye towards the nose. When viewing a distance object, the lens should be at rest. If the lens is working to bring a distant target into focus, the brain assumes the target must be close and automatically turns the eyes in. Often, a person will compensate by straightening one eye out to correctly view the distant target and let the other eye turn in. This results in a poor retinal image and lack of depth perception. Permanent loss of clear vision can result if this condition is not treated early in life. Usually, all that is needed, is to relax the natural lens, thereby relieving the need to converge the eyes, which results in both eyes in proper alignment. This can be done with corrective spectacle lenses for accommodative esotropia. If an eye is turned due to anatomical reasons, such as problems with muscles that control eye movement, then surgery may be required. No child is too young for an eye examination. We recommend a complete eye exam by the age of three or sooner whether there is any indication of visual problems or not. OHIP does cover eye exams up to the age of 20.
Amblyopia "Lazy Eye"
In some children, sight doesn’t develop properly in one eye even though that eye is structurally normal. This condition is called Amblyopia. Since amblyopia causes no discomfort, the child will not be aware that vision is decreased. It is caused by different images being sent to the brain from the two eyes: due to misaligned eyes (strabismus) or the eyes having very different optical powers. Treatment must begin as early as possible or the condition will cause poor vision for the rest of the child’s life. If the eyes are misaligned, then surgery or glasses will be used to straighten the eyes. If there is different optical powers, then the proper glasses will balance out the difference in magnification and image clarity. Patching of the better eye, forcing use of the other eye, may be required. Do not wait for your child to enter the school system and assume problems will be detected at that time. We recommend a full eye examination by the age 3 or sooner whether there is any indication of visual problems or not. OHIP does cover eye examinations up to the age of 20, along with adults with conditions such as amblyopia or strabismus.
Astigmatism - Is that a disease?
Astigmatism is not a disease. It is an optical defect that interferes with the eye’s ability to focus sharply, resulting in unclear vision. Astigmatism occurs when the shape of the cornea (the clear focusing surface that overlies the coloured iris), is not perfectly round like a baseball, but more oval, like a football. Heredity is the most common cause of astigmatism. It does not come from reading or using your eyes “too much” or reading in dim light. Astigmatic images are never sharp and crisp, either close up or in the distance. Straight lines running in one direction may be more blurred than lines running in another; for example, only the vertical edges of a window may appear out-of-focus. As you try to overcome the blur and see more clearly, you might get a headache from continually contracting the muscles around your eyes and furrowing your brows (actions that may be so automatic that you aren’t aware of them). Astigmatism can be optically corrected, and vision sharpened, by prescription eyeglasses or contact lenses. Glasses can also reduce the ocular “pulling”, dizziness, or difficulty with sustained reading. At first, the glasses can make objects look a bit tilted or distorted, but this should disappear after you get used to them. The amount of time you wear your correction will not have any effect on the basic astigmatism or its development - that is, wearing glasses or contacts will neither make the astigmatism better or worse. Astigmatism is easily diagnosed and corrected by your optometrist.
What are Floaters?
Floaters are translucent specks that seem to float about in your field of vision. Most people have floaters and they normally look like cobwebs, squiggly lines or floating bugs. Floaters become apparent when you look at something that is evenly bright, such as white paper or a blue sky, and are more evident when you move your eyes. Much of the interior of the human eyeball is filled with a clear, thick fluid that helps in maintaining the eye’s round shape. Light passes through this fluid and any bits of tissue will cast shadows onto the retina, and you see those shadows as something “floating” in your field of vision. Other occurrences can add more floaters. For example as your eyes age, the fluid in the eye may become stringy and the strands cast tiny shadows on the retina. Floaters can also come from old or new bleeding within the eye. They may be the result of a disease that causes opaque deposits in the fluid, an ocular inflammation that causes cellular debris, or they may be a residual from an old injury. In most cases floaters are simply an annoyance. However, the sudden appearance of new floaters accompanied by apparent flashes of light in the peripheral vision can be a sign that a vitreous detachment has occurred or, on rare occasions, these symptoms can be a danger sign that a retinal tear has occurred. The only way to diagnose the actual cause of the problem is by a complete eye examination with your optometrist.
What is Glaucoma?
Glaucoma is a general term used to describe an array of problems that affects the eye’s fluid drainage system. This leads to a build up of pressure within the eye that can damage the optic nerve and ultimately lead to blindness. The optic nerve is the connection between the eye and the brain that allows for vision. Any damage to the optic nerve leads to blind spots, or in severe cases, complete blindness. The most common type of glaucoma is called open-angle. This is created by a subtle increase in the eye pressure, similar to having high blood pressure. The real concern with this is that there are no symptoms such as pain, redness or blurred vision. The increased pressure gradually damages the optic nerve, reducing
the sensitivity of your peripheral vision first. This process is so gradual that it goes undetected. Glaucoma is also hereditary and this is why regular eye examinations are so important to catch this disease in the early stages. Treatment is very effective in controlling open-angle glaucoma, and in most cases will prevent any further damage to the optic nerve. Standard medication to start with is eye drops that will lower the eye pressure. If this is not effective enough, laser treatments to the drainage area of the eye are implemented next. The final treatment to lower the pressure would be a surgical procedure to drain the fluid from the eye. Optometrists are well equipped and trained to recognize the early signs of glaucoma and recommend visits on a regular basis.
What is Macular Degeneration?
The macula is the centermost part of the retina, the light-sensitive membrane of nerve tissue that lines the back of the eye. Although it’s no larger than a pinhead, the macula contains the visual cells needed for sharp vision and for seeing straight ahead. If those cells are damaged, it causes a loss of the central part of your visual field and makes it difficult or impossible to see fine detail and read small print. Central vision, normally your sharpest, most useful vision, may become so impaired that things you look at directly may seem blotted out, smudged, or shrouded in a dark haze. Because the condition tends to appear later in life, it is also called age-related macular degeneration, or AMD. AMD is the leading cause of poor vision in people over 60, though it can also occur at younger ages. Fortunately, peripheral vision remains normal, so even severe macular degeneration does not lead to total blindness. Heredity, long-term exposure to bright sunlight, smoking and other factors that normally accompany aging somehow interfere with the macula getting enough oxygen and nourishment, causing damage. There are two major types of AMD, called dry and wet. Most patients have the dry type, which tends to develop slowly as the tissue beneath the macula gradually deteriorates. There are dietary supplements that may help to slow the degeneration. The wet type occurs when these tissue changes are accompanied by the formation of tiny abnormal blood vessels under the retina which start to bleed or leak fluid. A laser is sometimes used to seal the leaks or to destroy the abnormal blood vessels formed under the macula. More information regarding Macular Degeneration can be obtained from your eye doctor.
Retinal detachment is a serious condition that can lead to severe visual impairment or even total blindness in the affected eye. The retina normally lies smoothly and firmly against the inside back wall of the eyeball. If any part of the retina is lifted or pulled from its normal position, it is considered detached, and will cause some vision loss. The detachment will almost always progress, and vision loss will increase, until it is treated. Therefore, any new detachment is always considered an emergency. A retinal detachment is caused by tiny tears or holes in the retina that can allow fluid to seep under the retina, separating it from the back wall of the eye. Retinal tears may also result from a hard blow or injury to the eye. When it tears, you are likely to have a sudden appearance of floaters - a shower of “cobwebs” in your field of vision - which may be accompanied by “flashes,” a sensation of seeing a flashing bright light. When a tear progresses to a detachment, a sensation of a “curtain of darkness “comes across your vision from any side. This is an emergency, and if your optometrist is unavailable you should seek medical attention immediately. Any change in visual symptoms regarding floaters and/or flashes of light should be investigated by your optometrist with a dilated retinal exam.
What is a stye?
A stye (hordeolum) is an abscess or mild infection associated with one or more of the glands along the eyelid margin or base of the eyelashes. You may first become aware of an aching and a feeling of fullness in the eyelid, followed in a day or so by some tenderness, swelling and redness. A small bump may form on the edge of the lid. As the bump grows it may form a “head” in the center and may drain a little pus, which dries to form flakes or crusts on the lashes. The usual treatment is to use warm soaks (compresses) on the eyelid two or three times a day. Moderate heat quickens the healing process by increasing circulation to the infected area and helps to unblock the affected glands. Medications are usually not necessary, though sometimes antibiotic eye drops and/or ointment may be prescribed for the eye if there is an associated bacterial infection. Most styes will resolve within a few weeks but if they persist or evolve into a hard non-tender nodule in the eyelid called a chalazion, they may need to be surgically removed. If you have repeated attacks of styes, you may be given oral antibiotics for 7 to 10 days in an attempt to fight the bacteria on the eyelids. As troublesome as they may be, styes do not threaten your eyesight, and their presence does not mean that you need glasses.