Eye Conditions

Nearsightedness (also known as Myopia) is a common vision condition in which you can see objects near you clearly, but objects farther away are blurry.

The degree of your nearsightedness determines your ability to focus on distant objects. People with severe nearsightedness can only clearly see objects just a few inches away, while those with mild nearsightedness may clearly see objects several yards away.

Nearsightedness may develop gradually or rapidly, often worsening during childhood and adolescence. Nearsightedness tends to run in families.

How is nearsightedness diagnosed?

Farsightedness (also known as Hyperopia) is a common vision condition in which you can see distant objects clearly, but objects nearby may be blurry.

The degree of your farsightedness determines your focusing ability. People with severe farsightedness may see near objects less clearly than distant objects, while those with mild farsightedness may be able to clearly see objects that are closer.

How is farsightedness diagnosed?

Glaucoma is not just one eye disease, but a group of eye conditions resulting in optic nerve damage, which causes loss of vision. Abnormally high pressure inside your eye (intraocular pressure) usually, but not always, causes this damage.

What are the symptoms of glaucoma?

Glaucoma is the second leading cause of blindness. Sometimes called the silent thief of sight, glaucoma can damage your vision so gradually you may not notice any loss of vision until the disease is at an advanced stage. The most common type of glaucoma, primary open-angle glaucoma, often has no noticeable signs or symptoms.

What causes glaucoma?

The cause of glaucoma is unknown. Nevertheless, it is generally associated with increased fluid pressure in the eye. Though, damage can also occur when eye pressure is normal and is called normal pressure or normal-tension glaucoma. Some theories suggest an inadequate blood supply or poor perfusion to the optic nerve is the cause.

How is glaucoma diagnosed?

Often, a comprehensive eye exam is the only way to detect glaucoma. During the exam, your doctor will measure the intraocular pressure, which is done to all patients. The “air puff” is known as a Non-Contact Tonometry (NCT). Tonometry is also done using eye drops (Goldmann).

While pressure is only one part of the glaucoma puzzle, the health of the optic nerve must also be evaluated. Using an optical coherence tomography (OCT) scan, the integrity of the optic nerve fibres, along with the peripheral vision field (side vision) using an automated visual field analyzer (Humphrey Visual Field Analyser), can be evaluated.

Early diagnosis and treatment can minimize or prevent optic nerve damage and limit glaucoma-related vision loss. It’s important to get your eyes examined regularly and make sure your eye doctor measures your intraocular pressure.

How is glaucoma treated?

When a diagnosis of damage is made, treatment consists of lowering eye pressure.

A cataract is a clouding of the normally clear lens of your eye. For people who have cataracts, seeing through cloudy lenses is a bit like looking through a frosty or fogged-up window. Clouded vision caused by cataracts can make it more difficult to read, drive a car (especially at night), or see the expression on a friend’s face.

What are the symptoms of cataracts?

Most cataracts develop slowly and don’t disturb your eyesight early on. But with time, cataracts will eventually interfere with your vision.

Common symptoms are: blurry or foggy vision, decreased night vision, halos around lights, colours appear dull or muted, feel as though a film is covering your eye, or sunlight and other light seems overly bright or glaring.

How are cataracts treated?

At first, stronger lighting and eyeglasses can help you deal with cataracts. But if impaired vision interferes with your usual activities, you might need cataract surgery. Fortunately, cataract surgery is generally a safe, effective procedure.

Astigmatism is a common eye condition that occurs in nearly everybody to some degree and is easily corrected by eyeglasses, contact lenses, or surgery. Astigmatism is characterized by an irregular curvature of the cornea and is one type of refractive error. For significant curvature, treatment is required.

A person’s eye is naturally spherical in shape. Under normal circumstances, when light enters the eye, it refracts evenly, creating a clear view of the object. However, the eye of a person with astigmatism is shaped more like a football or the back of a spoon. For this person, when light enters the eye it is refracted more in one direction than the other, allowing only part of the object to be in focus at one time. Objects at any distance can appear blurry and wavy.

What are the symptoms of astigmatism?

People with undetected astigmatism often experience headaches, fatigue, eyestrain, and blurred vision at all distances. While these symptoms may not necessarily be the result of astigmatism, you should schedule an eye exam if you are experiencing one or more symptoms.

What causes astigmatism?

Astigmatism can be hereditary and is often present at birth. It can also result from pressure from the eyelids on the cornea, incorrect posture, or increased use of the eyes for close work.

How is astigmatism diagnosed?

Your optometrist can diagnose astigmatism with a thorough eye exam. Astigmatism may occur with other refractive errors such as myopia (nearsightedness) and hyperopia ( farsightedness). Unfortunately, astigmatism often goes undetected in school-age children.

Because astigmatism may increase slowly, you should visit your eye doctor whenever you notice significant changes in your vision.

How is astigmatism treated?

Almost all degrees of astigmatism can be corrected with properly prescribed eyeglasses or contact lenses. For a person with only a slight degree of astigmatism, corrective lenses may not be needed at all, as long as other conditions such as nearsightedness or farsightedness are not present. If the astigmatism is moderate to high, however, corrective lenses are probably needed.

Corrective lenses (eyeglasses or contact lenses)

For astigmatism, special corrective lenses called toric lenses are prescribed. Toric lenses have greater light bending power in one direction than the other. After performing various tests, your eye doctor will determine the ideal toric lens prescription for your astigmatism.

Refractive surgery

Another method for correcting astigmatism is by changing the shape of the cornea through refractive or laser eye surgery. While there is more than one type of refractive surgery, specific treatments are recommended on an individual basis.

Refractive surgeries require healthy eyes that are free from retinal problems, corneal scars, and any eye disease. As technology progresses, it is becoming more and more important that you explore all options and possibilities before deciding which refractive surgery and treatment are right for you.

Presbyopia is the gradual loss of your eye’s ability to focus actively on nearby objects. A natural, often annoying part of aging, presbyopia usually becomes noticeable in your early to mid-40s and continues to worsen until around age 65. Presbyopia affects everyone, even those who’ve never had vision problems before.

What are the symptoms of presbyopia?

You may become aware of presbyopia when you start holding reading materials and cell phones at arm’s length to be able to read them. If you’re nearsighted, you might temporarily manage presbyopia by reading without your glasses. Eye strain, headache, and fatigue are common symptoms of presbyopia.

What causes presbyopia?

Most experts believe presbyopia is caused by changes to the lens inside the eye. As people age, the lens becomes harder and less elastic, making it more difficult for the eye to focus on close objects.

How is presbyopia diagnosed?

A comprehensive eye exam will include testing that will determine the quality of your near vision, and, if present, the diagnosis of presbyopia.

How is presbyopia treated?

For centuries presbyopia was corrected with the use of bifocal eyeglasses. That being said, presbyopia can be corrected with eyeglasses, contact lenses, or surgery. Don’t forget, a basic eye exam can confirm presbyopia.

Amblyopia, commonly known as lazy eye, is a condition where vision in one of the eyes is reduced because the eye and the brain are not working together properly. The visual loss in amblyopia cannot be corrected by just wearing glasses.

Amblyopia is the most common cause of visual impairment during childhood. The condition affects approximately two to three out of every 100 children. It is thought to develop early in life during the critical period of visual development. Unless it is successfully treated in early childhood, amblyopia usually persists into adulthood and is the most common cause of monocular (one eye) visual impairment among children and young and middle-aged adults.

What are the symptoms of amblyopia?

The symptoms of amblyopia include eyes that turn in or out, eyes that do not appear to work together, inability to judge depth correctly, and poor vision in one eye.

What causes amblyopia?

Amblyopia may be caused by any condition that affects normal visual development or use of the eyes. Strabismus, which is an imbalance in the positioning of the two eyes, is the most common cause of amblyopia. Strabismus can cause the eyes to cross in (esotropia) or turn out (exotropia). Other causes of amblyopia include childhood cataracts, nearsightedness, farsightedness, and astigmatism. There is often a family history of this condition.

How is amblyopia diagnosed?

In general, the earlier the child has the condition, the worse it may become. Similarly, the earlier the treatment is started, the better the opportunity to reverse vision loss.

Before treating amblyopia, it may be necessary to first treat the underlying cause. Glasses are commonly prescribed to improve focusing or misalignment of the eyes. Surgery may be performed on the eye muscles to straighten the eyes if non-surgical means are unsuccessful. Surgery can help in the treatment of amblyopia by allowing the eyes to work together better. Eye exercises may also be recommended either before or after surgery to correct faulty visual habits associated with strabismus and to teach comfortable use of the eyes.

Following treatment of the underlying cause, patching or covering one eye may be required for a period of time. The better-seeing eye is patched, forcing the “lazy” one to work, thereby strengthening its vision.

Amblyopia is usually easily diagnosed with a complete examination of the eyes. Special tests are usually not needed.

How is amblyopia treated?

A comprehensive eye exam can determine the presence of amblyopia, which is why it is important to have your child’s vision examined at six months of age, again at three, and then regularly thereafter. Keep in mind that the earlier amblyopia is diagnosed, the greater the chance for a complete recovery.

If you have been diagnosed with diabetes, you may be at risk of losing your vision since your body does not utilize sugar properly and, when the sugar levels rise, damage to the retinal blood vessels may occur. This injury to the retinal vessels is known as diabetic retinopathy. Diabetic Retinopathy is the leading cause of blindness in working-age adults.

What are the symptoms of diabetic retinopathy?

Often, one may not be aware of any symptoms even when significant diabetic retinopathy is present. When macular edema occurs, vision often becomes blurry and may fluctuate. If abnormal new blood vessels form, as in proliferative diabetic retinopathy, they may bleed and result in small specks or large floaters obscuring the vision. If a large hemorrhage occurs, vision often becomes very blurry.

How is diabetic retinopathy diagnosed?

A comprehensive eye examination by an optometrist or retina specialist is the only reliable means of detecting diabetic retinopathy. After the pupil is dilated, the retina is examined to determine the extent of the retinopathy. If diabetic retinopathy is discovered, a fluorescein dye test and/or optical coherence tomogram (OCT) may be recommended. A fluorescein angiogram involves the injection of a dye into a vein in the arm followed by several minutes of intermittent photos with a special digital camera focused on the retina. An OCT is a non-invasive photo that creates a detailed cross-sectional image of the macula.

How is diabetic retinopathy treated?

The best therapy for diabetic retinopathy is prevention. Studies show that strict control of blood sugar levels can significantly lower the risk of vision loss from diabetic retinopathy. High blood pressure and kidney problems should also be treated to minimize their effect on retinopathy.

Laser surgery is often the first line of treatment if macular edema or proliferative retinopathy is present. For macular edema, the laser is focused on leaky areas of the retina to aid in reabsorbing the excess fluid. The primary goal of this treatment is to prevent further vision loss.

It is uncommon for people to recover significant vision following treatment but some do experience partial restoration. Laser surgery is not a cure for diabetic retinopathy and is not guaranteed to prevent further loss of vision. Newer treatments for diabetic retinopathy include a novel class of medication called anti-VEGF. This drug is injected into the eye to inhibit the growth of proliferative and leaky blood vessels.

Keratoconus is an eye condition in which the shape of the cornea becomes distorted. The cornea is a clear structure that covers the front of the eye and allows light to enter the eye. In a healthy eye, the cornea curves like a dome. In an eye with keratoconus, the center of the cornea slowly thins and bulges so that it sags and has a cone shape.

What are the symptoms of keratoconus?

Keratoconus tends to affect younger people and the symptoms sometimes start in the early teen years and progress rapidly for the next 10 to 20 years. Often, eyeglass prescriptions must be changed frequently as the disease progresses.

Symptoms include difficulty driving at night, halo’s and ghosting, especially at night, eyestrain, headaches and general eye pain, and eye irritation, and excessive rubbing of the eye.

What causes keratoconus?

The cause of keratoconus is unknown.

How is keratoconus diagnosed?

Keratoconus can usually be diagnosed with a slit-lamp examination and with a measurement of the corneal curvature. Corneal Topography gives us a coloured map of the corneal surface. Your optometrist will look for signs such as corneal thinning, stress lines, and scarring at the apex of the corneal cone.

Keratoconus, especially in the early stages, can be difficult to diagnose and its symptoms could be associated with other eye problems. Simply recognizing symptoms does not by itself diagnose the condition.

How is keratoconus treated?

The primary treatment options for keratoconus are contact lenses and surgery. In the very early stages of keratoconus, vision problems can be corrected with prescription glasses or contact lenses. As keratoconus progresses, special rigid gas permeable contact lenses may be necessary. Advanced keratoconus may require surgery.

The term “macular degeneration” includes many different eye diseases, all of which affect central or detailed vision.

Age-related macular degeneration (ARMD) is the most common of these disorders, mainly affecting people over the age of 60. This condition occurs in two forms: “wet” age-related macular degeneration (AMD) and “dry” age-related macular degeneration (AMD).

What is wet age-related macular degeneration?

“Wet” AMD is less common but more aggressive in its development to severe central vision loss. It occurs when abnormal blood vessels begin to grow underneath the retina. These new blood vessels (known as choroidal neovascularization or CNV) tend to be very fragile and often leak blood and fluid. The blood and fluid raise the macula from its normal place at the back of the eye and interfere with the retina’s function and causes the central vision to blur.

Under these circumstances, vision loss may be rapid and severe. Some patients, however, do not notice visual changes despite the onset of CNV. Therefore, periodic eye examinations are very important for patients at risk for CNV. Once CNV has developed in one eye, whether there is a visual loss or not, the other eye is at relatively high risk for the same change.

What is dry age-related macular degeneration?

“Dry” age-related macular degeneration (AMD) is the more common type but slowly progressive in causing loss of vision. In dry AMD, the light-sensitive cells in the macula slowly break down. With less of the macula functioning, central vision diminishes. It often occurs in just one eye at first. Later, the other eye can be affected. The dry form is much more common than the wet form. Dry AMD can advance and cause vision loss without turning into wet AMD. It can also rapidly transform into the wet form by the growth of new blood vessels.

What are the symptoms of macular degeneration?

Neither dry nor wet AMD causes any eye pain.

The most common early symptom in dry AMD is blurred vision. Dry AMD symptoms usually develop gradually and do not include total blindness. However, the symptoms may worsen the quality of life by making reading, driving, and facial recognition difficult.

Other symptoms may include decreased night vision, a decrease in the intensity or brightness of colours, increase in the haziness of overall vision.

All of the above symptoms may also be noticed in the wet form of AMD. In addition, the most common symptom in wet AMD is straight lines appearing crooked or wavy.

What causes macular degeneration?

We do not know the precise cause for the development of ARMD. However, we do know that the greatest risk factor is age. In fact, studies show that people over age 60 are clearly at greater risk than other age groups.

Note: Your lifestyle can play a role in reducing your risk of developing AMD. This includes:

Wet AMD can be treated with laser surgery and injections into the eye. None of these treatments is a permanent cure for wet AMD. The disease and loss of vision may continue to grow despite treatment.

There is currently no treatment available to reverse dry macular degeneration. However, dry macular degeneration usually develops at a slower pace and most patients with this condition are able to live relatively normal, productive lives. Often one eye is affected more than the other.

How is macular degeneration treated?

A thorough examination by an eye doctor is the best way to determine if you have macular degeneration or if you are at risk for developing the condition.

The exam begins by testing your visual acuity or the sharpness of your vision. There are several different tests for visual acuity. The most familiar one has lines of black letters on a white chart.

Next, your eyes may be tested with an Amsler grid. This test helps your doctor determine if you are experiencing areas of distorted or reduced vision, both common symptoms of macular degeneration. If you do have macular degeneration, your doctor will use the Amsler grid to determine if your vision has changed.

After these visual tests, the front part of your eyes will be examined to determine if everything is healthy. Your doctor may put anesthetic drops in your eyes before measuring the pressure in each eye. Drops are also administered, which cause your pupils to dilate. This will allow your doctor to examine the retina through the enlarged pupil. After the dilating drops are administered and allowed time to work, the eye doctor will then use a slit-lamp to examine the eyes. The slit-lamp is a special microscope that enables the doctor to examine the different parts of the eye under magnification. When used with handheld lenses, the slit-lamp gives the examiner a highly magnified view of the retina.

An optical coherence tomography (OCT) scan may also be used to evaluate the deeper layer of the retina (macula), which cannot be visualized by examining the surface of the macula. In conducting an OCT, an earlier diagnosis is possible. That is why an OCT scan is routinely incorporated in a comprehensive eye exam.

While contact lenses are safely worn by many, there is a risk of developing eye infections. Factors that contribute to an infection can include:

The best way to avoid eye infections due to wearing contact lenses is to follow proper lens care guidelines as recommended by your optometrist. You can help reduce the risk of infection by carefully cleaning, rubbing, and rinsing your contacts, minimizing contact with water while wearing them and replacing the lens case often.

Some of the most common eye infections associated with wearing contact lenses.

Corneal ulcers

A corneal ulcer is an erosion or exposed sore on the surface of the cornea. Corneal ulcers are most commonly caused by bacteria. Other causes of corneal ulcers include viruses, injury and inadequate eyelid closure. Corneal ulcers are most common in people who wear contact lenses.

What are the symptoms of corneal ulcers?

The symptoms of corneal ulcers include redness, pain, tearing, discharge, white spot on the cornea, blurry vision, burning, itching, and light sensitivity.

How are corneal ulcers diagnosed and treated?

Early diagnosis is important in treating corneal ulcers. Your optometrist will ask you questions to determine what caused the ulcer. Your eyes will then be examined with a slit-lamp. A special dye may be placed in your eye to aid in the diagnosis. If it is not clear what the exact cause is, your optometrist may test a sample of the ulcer in order to properly treat it.

Treatment for corneal ulcers needs to be aggressive, as some ulcers can lead to vision loss and blindness. Treatment usually involves antibiotics as well as antiviral medications. Steroid eye drops may also be given to reduce inflammation. In severe cases, a corneal transplant may be needed to restore vision. If treatment is not administered, there may be blindness or even total loss of the eye.

Contact Lens Induced Acute Red Eye (CLARE)

CLARE is an inflammatory reaction of the cornea and conjunctiva (a thin and transparent membrane that covers the sclera, the white part of the eye). This infection is mostly caused by sleeping with contact lenses and is characterized by waking with red eyes.

What is the treatment for CLARE?

In most cases, no treatment is required. It is recommended that patients discontinue lens wear, which usually remedies the condition. However, if redness or irritation persists after 24-hours, you should see your optometrist. If you experience pain, sensitivity to light or a decrease in vision, you should see your optometrist immediately.

Giant Papillary Conjunctivitis (GPC)

GPC is an inflammatory reaction of the upper eyelid and is very common among those that wear contact lenses.

What are the symptoms of GPC?

Your optometrist may prescribe pharmaceutical eye drops such as anti-histamines and recommend that you stop wearing contacts until the condition goes away.

What is the treatment for GPC?

The symptoms of GPC include small, red bumps (papules) on the inflamed tissue on the underside of the upper eyelids. There is usually itchiness, discharge, increased lens awareness, and decreased lens tolerance.

Strabismus (also referred to as crossed eyes, deviation, squint, or tropia) is a condition where both of your eyes do not look toward the same object together.

There are six different muscles that surround the eyes and work together so that both eyes can focus on the same object. For someone with strabismus, these muscles do not work together. As a result, one eye looks at one object, while the other eye turns in a different direction and is focused on another object. When this happens, two different images, one from each eye, are sent to the brain. This confuses the brain, and the brain may learn to ignore the image from the weaker eye.

Strabismus is a common condition among children but it can also occur later in life.

What are the symptoms of strabismus?

The main sign of strabismus is an eye that is not directed straight. Sometimes a child or young person will squint with one eye in bright sunlight. Symptoms of faulty depth perception may also be noticed. Adults with strabismus will usually have double vision.

What causes strabismus?

Your eyes’ coordination and ability to work together as a team develop in your first six to eight years. The failure of eye muscles to work together properly can lead to strabismus. Strabismus has a tendency to be hereditary, but may also be acquired secondary to an eye injury or disease.

How is strabismus treated?

Treatment of strabismus may consist of eyeglasses, patching, eye coordination exercises (called orthoptics), and/or surgery on the eye muscles.

Eyeglasses, with or without patching, are often the treatment tried first and can usually reduce the amount of deviation.

How is strabismus diagnosed?

Strabismus is usually diagnosed with a physical examination that includes a detailed examination of the eyes. Tests are done to determine how much the eyes are out of alignment. These eye tests may include corneal light reflex, cover/uncover test, retinal exam, standard exam and visual acuity.

Also known as Pink Eye, conjunctivitis is an inflammation of the conjunctiva – the thin, transparent layer that covers the inner eyelid and the white portion at the front of the eye (the sclera). The irritation will cause blood vessels contained in the conjunctiva to dilate, which is what causes red or bloodshot eyes. It is often associated with either watery discharge or sticky mucous discharge.

While it is common among children and may be caused by a minor infection, all ages may be affected. It is important to remember that some forms of conjunctivitis may develop into a more serious problem if not diagnoses and treated properly.

What are the symptoms of conjunctivitis?

Those who have contracted conjunctivitis may experience pink discolouration to the whites of the eye(s), itching or burning sensation, swollen eyelid(s), sensitivity to light, excessive tearing, or sticky yellow/watery/stringy discharge from the eye(s).

What causes conjunctivitis?

How is conjunctivitis treated?

Blepharitis is a common chronic external eye condition that causes inflammation of the eyelids.

What are the symptoms of blepharitis?

Symptoms of blepharitic include red, burning, and irritated eyes.

What causes blepharitis?

Inflammation of the oil glands (responsible for producing the outermost layer of tears) that are located behind the eyelashes is what causes blepharitis. When blepharitis occurs, the oils from these glands do not flow freely and the gland openings become plugged. If left untreated, these glands can become irritated and possibly infected. Loss of eyelashes can occur as well as recurrent painful eyelid swelling or styes. Dandruff-like scales may be found at the base of the eyelashes.

In addition to their eyelids being matted shut, many patients will complain of burning eyes that are at their worst in the morning upon waking. There are several causes as to why these glands become inflamed and frequently occurs in people who have a tendency towards oily skin and dandruff. It can happen at any age.

How is blepharitis treated?

The vitreous is a semi-solid to liquid material that occupies up to 75 percent of the eyeball volume. It is contained within a thin sac that is tightly adhered to the retina, or the inner layer of the eye. One role of the vitreous is to keep the eyeball inflated much like air in a soccer ball. However, the vitreous sac can pull away from the retina and shrink as we age.

What are the symptoms of vitreous?

Over time, the fibres of the vitreous become more mobile and clump together forming floaters. The floaters cast a shadow on the retina, which may appear to the individual as a dust particle or a tiny insect floating in your vision. The vitreous sac may then pull away from the retina resulting in the sudden onset of flashing lights accompanying the floaters. These symptoms of vitreous detachment are similar to retinal detachment. However, vitreous detachment does not have the same potential of vision damage that retinal detachment does.

What causes vitreous?

Vitreous detachment may occur spontaneously, or after eye surgery, physical trauma to the head or eye, or due to an inflammatory process.

How is vitreous treated?

Even though the appearance of flashes and floaters from a vitreous detachment can be more of a nuisance than anything, you should have your eyes examined by a doctor of optometry right away if you notice any sudden changes in vision, such as new floaters, flashes, or light. You will need to have your pupils dilated to ensure the health of the retina. A cautious approach can go a long way towards preserving vision.

The tears your eyes normally produce are necessary for overall eye health and clear vision. Dry eye occurs when your eyes do not produce enough tears or produce tears that do not have the proper chemical composition.

What are the symptoms of dry eye?

Common signs and symptoms of dry eye include stinging, gritty, scratchy and uncomfortable eyes, fluctuating vision, and sometimes having a burning feeling or a feeling of something foreign within the eye. Some people experience tearing as a result of dry eye. This is a natural reflex of the eyes to create more tears to comfort the eye in response to dryness.

What causes dry eye?

Dry eye symptoms can result from the normal aging process, hormonal changes, exposure to certain environmental conditions, problems with normal blinking, or from medications such as antihistamines, oral contraceptives, or antidepressants. Dry eye can also be symptomatic of general health problems, such as arthritis, or can result from UV exposure and environmental irritants.

How is dry eye treated?

Dry eye is usually chronic and cannot be cured, but your comfort can be improved and eye health maintained with the following:

How is dry eye diagnosed?

During the examination, your doctor will ask you questions about your general health, your use of medications, and your home and work environments to determine any factors which may be causing dry eye symptoms. This information will help your doctor decide whether to perform additional dry eye testing. The use of a high-powered microscope known as a slit lamp, in conjunction with special dyes, will help evaluate the quality, the amount, and the distribution of tears to detect signs of dry eyes.