On August 4th, 2010, posted in: Eye & Vision Problems by

A cataract is a cloudy or opaque area in the normally clear lens of the eye. Depending upon its size and location, it can interfere with normal vision. Most cataracts develop in people over age 55, but they occasionally occur in infants and young children. Usually cataracts develop in both eyes, but one may be worse than the other. Reasearchers have linked eye-friendly nutrients such as lutein/zeaxanthin, vitamin C, vitamin E, and zinc to reducing the risk of certain eye diseases, including cataracts. For more information on the importance of good nutrition and eye health, please see the diet and nutrition section.

The lens is located inside the eye behind the iris, the colored part of the eye. The lens focuses light on the back of the eye, the retina. The lens is made of mostly proteins and water. Clouding of the lens occurs due to changes in the proteins and lens fibers.

The lens is composed of layers like an onion. The outermost is the capsule. The layer inside the capsule is the cortex, and the innermost layer is the nucleus. A cataract may develop in any of these areas and is described based on its location in the lens:

  • A nuclear cataract is located in the center of the lens. The nucleus tends to darken changing from clear to yellow and sometimes brown.
  • A cortical cataract affects the layer of the lens surrounding the nucleus. It is identified by its unique wedge or spoke appearance.
  • A posterior capsular cataract is found in the back outer layer of the lens. This type often develops more rapidly.

Normally, the lens focuses light on the retina, which sends the image through the optic nerve to the brain. However, if the lens is clouded by a cataract, light is scattered so the lens can no longer focus it properly, causing vision problems.

Cataracts generally form very slowly. Signs and symptoms of a cataract may include:

  • Blurred, hazy, or vision
  • Reduced intensity of colors
  • Increased sensitivity to glare from lights, particularly when driving at night
  • Increased difficulty seeing at night
  • Change in the eye’s refractive error

While the process of cataract formation is becoming more clearly understood, there is no clinically established treatment to prevent or slow their progression. In age-related cataracts, changes in vision can be very gradual. Some people may not initially recognize the visual changes. However, as cataracts worsen vision symptoms tend to increase in severity.

Causes of cataracts

Most cataracts are due to age-related changes in the lens. However, other factors can contribute to their development including:

  • Diabetes mellitus – Persons with diabetes are at higher risk for cataracts.
  • Drugs – Certain medications have been found to be associated with the development of a cataract. These include:
    • Corticosteroids
    • Chlorpromazine and other phenothiazine related medications
  • Ultraviolet radiation – Studies have shown that there is an increased chance of cataract formation with unprotected exposure to ultraviolet (UV) radiation.
  • Smoking – An association between smoking and increased nuclear opacities has been reported.
  • Alcohol – Several studies have shown increased cataract formation in patients with higher alcohol consumption compared with people who have lower or no alcohol consumption.
  • Nutritional deficiency – Although the results are inconclusive, studies have suggested an association between cataract formation and low levels of antioxidants (e.g. vitamin C, vitamin E, carotenoids). Further studies may show that antioxidants have a significant effect on decreasing cataract development.

Rarely, cataracts can be present at birth or develop shortly after. They may be inherited or develop due to an infection, i.e. rubella, in the mother during pregnancy. A cataract may also develop following an injury to the eye or surgery for another eye problem, such as glaucoma.

While there are no clinically proven approaches to preventing cataracts, simple preventive strategies include reducing exposure to sunlight through UV blocking lenses, decreasing or discontinuing smoking and increasing antioxidant vitamin intake through consumption of leafy green vegetables and nutritional supplements.

Diagnosis of cataracts

Cataracts can be diagnosed through a comprehensive eye examination. This examination may include:

  • Patient history to determine vision difficulties experienced by the patient that may limit their daily activities and other general health concerns affecting vision.
  • Visual acuity measurement to determine to what extent a cataract may be limiting clear vision at distance and near.
  • Refraction to determine the need for changes in an eyeglass or contact lens prescription.
  • Evaluation of the lens under high magnification and illumination to determine the extent and location of any cataracts.
  • Evaluation of the retina of the eye through a dilated pupil.
  • Measurement of pressure within the eye.
  • Supplemental testing for color vision and glare sensitivity.

Additional testing may be needed to determine the extent of impairment to vision caused by a cataract and to evaluate whether other eye diseases may limit vision following cataract surgery.

Using the information obtained from these tests, your optometrist can determine if you have cataracts and advise you on options for treatment.

How is a cataract treated?

The treatment of cataracts is based on the level of visual impairment they cause.

If a cataract affects vision only minimally, or not at all, no treatment may be needed. Patients may be advised to monitor for increased visual symptoms and follow a regular check-up schedule.

In some cases, a change in eyeglass prescription may provide temporary improvement in visual acuity. Increasing the amount of light used when reading may be beneficial. The use of anti-glare coatings on clear lenses can help reduce glare for night driving.

When a cataract progresses to the point that it affects a person’s ability to do normal everyday tasks, surgery may be needed. Cataract surgery involves removing the lens of the eye and replacing it with an artificial lens. The artificial lens requires no care and can significantly improve vision. New artificial lens options include those that simulate the natural focusing ability of a young healthy lens.

Two approaches to cataract surgery are generally used:

  • Small incision cataract surgery involves making an incision in the side of the cornea, the clear outer covering of the eye, and inserting a tiny probe into the eye. The probe emits ultrasound waves that soften and break-up the lens so it can be removed by suction. This process is called phacoemulsification.
  • Extracapsular surgery requires a somewhat larger incision in the cornea and the lens core is removed in one piece.

Once the natural lens has been removed, it is replaced by a clear plastic lens called an intraocular lens (IOL). For situations where implanting an IOL is not possible because of other eye problems, contact lenses and in some cases eyeglasses may be an option to provide needed vision correction.

As with any surgery, cataract surgery has risks from infection and bleeding. Cataract surgery also slightly increases the risk of retinal detachment. It is important to discuss the benefits and risks of cataract surgery with your eye care providers. Other ocular conditions may increase the need for cataract surgery or prevent a person from being a cataract surgery candidate.

Cataract surgery is one of the safest and most effective types of surgery performed in the United States today. Approximately 90 percent of cataract surgery patients report better vision following the surgery.

American Optometric Association, 8/4/10

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On August 4th, 2010, posted in: Eye & Vision Problems by

A chalazion is a slowly developing lump that forms due to blockage and swelling of an oil gland in the eyelid. It is more common in adults than children and occurs most frequently in persons 30 to 50 years of age.

Initially, a chalazion may appear as a red, tender, swollen area of the eyelid. However, in a few days it changes to a painless, slow growing lump in the eyelid. A chalazion often starts out very small and is barely able to be seen, but it may grow to the size of a pea. Often times they may be confused with sties, which are also areas of swelling in the eyelid.

A sty is an infection of an oil gland in the eyelid. It produces a red, swollen, painful lump on the edge or inside surface of the eyelid. Sties usually occur closer to the surface of the eyelid than do chalazia.

A chalazion is generally not due to an infection, but results from a blockage of the oil gland itself. However, a chalazion may occur as an after-effect of a sty.

Common signs or symptoms of a chalazion include:

  • Appearance of a painless bump or lump in the upper eyelid, or, less commonly, in the lower eyelid
  • Tearing
  • Blurred vision, if the chalazion is large enough to press against the eyeball

Most chalazia disappear without treatment in several weeks to a month. However, they often recur. Rarely, they may be an indication of an infection or skin cancer.

What causes a chalazion?

A chalazion can develop when the oil produced by glands within the eyelids, called the meibomian glands, becomes thickened and is unable to flow out of the gland. The oil builds up inside the gland and forms a lump in the eyelid. Eventually the gland may break open and release the oil into the surrounding tissue causing an inflammation of the eyelid.

Risk factors for the development of a chalazion include:

  • Chronic blepharitis, an inflammation of the eyelids and eye lashes
  • Acne rosacea
  • Seborrhea
  • Tuberculosis
  • Viral infection

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How is a chalazion diagnosed?

A chalazion can be diagnosed through a comprehensive eye examination. Testing, with special emphasis on evaluation of the eyelids, may include:

  • Patient history to determine any symptoms the patient is experiencing and the presence of any general health problems that may be contributing to the eye problem.
  • External examination of the eye, including lid structure, skin texture and eyelash appearance.
  • Evaluation of the lid margins, base of the eyelashes and oil gland openings using bright light and magnification.

Using the information obtained from testing, your optometrist can determine if you have a chalazion and advise you on treatment options.

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How is a chalazion treated?

Many chalazia require minimal medical treatment, resolving on their own in a few weeks to a month. To facilitate healing, warm compresses can be applied to the eyelid for 10 to15 minutes 4 to 6 times a day for several days. The warm compresses may help soften the hardened oil that is blocking the ducts thereby promoting drainage and healing. Lightly messaging the external area of the eyelid for several minutes each day may also help to promote drainage.

A clean soft cloth dipped in warm water and wrung out can serve as an effective compress. Remoisten the cloth frequently to keep it wet and warm. Once the chalazion drains on its own, keep the area clean and keep your hands away from your eyes.

If the chalazion does not drain and heal within a month, contact your eye doctor. Don’t attempt to squeeze or drain the chalazion yourself.

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American Optometric Association, 8/4/10

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Color vision deficiency is the inability to distinguish certain shades of color or in more severe cases, see colors at all. The term “color blindness” is also used to describe this visual condition, but very few people are completely color blind.

Most people with color vision deficiency can see colors, but they have difficulty differentiating between

  • particular shades of reds and greens (most common) or
  • blues and yellows (less common).

People who are totally color blind, a condition called achromatopsia, can only see things as black and white or in shades of gray.

The severity of color vision deficiency can range from mild to severe depending on the cause. It will affect both eyes if it is inherited and usually just one if the cause for the deficiency is injury or illness.

Color vision is possible due to photoreceptors in the retina of the eye known as cones. These cones have light sensitive pigments that enable us to recognize color. Found in the macula, the central portion of the retina, each cone is sensitive to either red, green or blue light, which the cones recognize based upon light wavelengths.

Normally, the pigments inside the cones register differing colors and send that information through the optic nerve to the brain enabling you to distinguish countless shades of color. But if the cones lack one or more light sensitive pigments, you will be unable to see one or more of the three primary colors thereby causing a deficiency in your color perception.

The most common form of color deficiency is red-green. This does not mean that people with this deficiency cannot see these colors at all; they simply have a harder time differentiating between them. The difficulty they have in correctly identifying them depends on how dark or light the colors are.

Another form of color deficiency is blue-yellow. This is a rarer and more severe form of color vision loss than red-green since persons with blue-yellow deficiency frequently have red-green blindness too. In both cases, it is common for people with color vision deficiency to see neutral or gray areas where a particular color should appear.

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What causes color vision deficiency?

Usually, color deficiency is an inherited condition caused by a common X-linked recessive gene, which is passed from a mother to her son. But disease or injury damaging the optic nerve or retina can also result in loss of color recognition. Some specific diseases that can cause color deficits are:

  • diabetes
  • glaucoma
  • macular degeneration
  • Alzheimer’s disease
  • Parkinson’s disease
  • multiple sclerosis
  • chronic alcoholism
  • leukemia
  • sickle cell anemia

Other causes for color vision deficiency include:

  • Medications – certain medications such as drugs used to treat heart problems, high blood pressure, infections, nervous disorders and psychological problems can affect color vision.
  • Aging – the ability to see colors can gradually lessen with age.
  • Chemical Exposure – contact with certain chemicals such as fertilizers and styrene have been known to cause loss of color vision.

In the majority of cases, genetics is the predominate cause for color deficiency. About 8% of caucasian males are born with some degree of color deficiency. Women are typically just carriers of the color deficient gene, though approximately 0.5% of women have color vision deficiency. When the deficiency is hereditary, the severity generally remains constant throughout life. Inherited color vision deficiency does not lead to additional vision loss or blindness.

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How is color vision deficiency diagnosed?

Color deficiency can be diagnosed through a comprehensive eye examination. Testing will include the use of a series of specially designed pictures composed of colored dots, called pseudisochromatic plates, which include hidden numbers or embedded figures that can only be correctly seen by persons with normal color vision.

  • Pseudoisochromatic testing plates. The patient is asked to look for numbers among the various colored dots, which help distinguish between red, green and blue color deficiencies. Individuals with normal color vision will see a number, while those with a deficiency do not see it. On some plates, a person with normal color vision may see one number, while a person with a  deficiency sees a different number.

Pseudoisoschromatic plate testing can be used to determine if a color vision deficiency exists and the type of deficiency. However, additional testing may be needed to determine the exact nature and degree of color deficiency.

It is possible for a person to have poor color vision and not know it. Quite often, people with red-green deficiency aren’t even aware of their problem since they’ve learned to see the “right” color. For example, tree leaves are green, so they call the color they see green.

Also parents may not suspect the condition in their children until a situation causes confusion or misunderstanding. Early detection of color deficiency is vital since many learning materials rely heavily on color perception or color coding. That is one reason that the American Optometric Association recommends a comprehensive optometric examination before a child begins school.

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How is color vision deficiency treated?

There is no cure for inherited color deficiency. But if the cause is an illness or eye injury, treating these conditions may improve color vision.

Using special tinted eyeglasses or wearing a red tinted contact lens on one eye can increase some people’s ability to differentiate between colors, though nothing can make you truly see the deficient color.

Most color deficient persons compensate for their inability to distinguish certain colors with color cues and details that are not consciously evident to people with normal color vision. There are ways to work around the inability to see certain colors by:

  • Organizing and labeling clothing, furniture or other colored objects (with the help of friends or family) for ease of recognition.
  • Remembering the order of things rather than their color can also increase the chances of correctly identifying colors. For example a traffic light has red on top, yellow in the middle and green on the bottom.

Though color vision deficiency can be a frustration and may limit participation in some occupations, in most cases it is not a serious threat to vision and can be adapted to your lifestyle with time, patience and practice.

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American Optometric Association, 8/4/10

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Conjunctivitis is an inflammation or infection of the conjunctiva, the thin transparent layer of tissue that lines the inner surface of the eyelid and covers the white part of the eye. Conjunctivitis, often called “pink eye,” is a common eye disease, especially in children. It may affect one or both eyes. Some forms of conjunctivitis can be highly contagious and easily spread in schools and at home. While conjunctivitis is usually a minor eye infection, sometimes it can develop into a more serious problem.

Conjunctivitis may be caused by a viral or bacterial infection. It can also occur due to an allergic reaction to irritants in the air like pollen and smoke, chlorine in swimming pools, and ingredients in cosmetics or other products that come in contact with the eyes. Sexually transmitted diseases like Chlamydia and gonorrhea are less common causes of conjunctivitis.

People with conjunctivitis may experience the following symptoms:

  • A gritty feeling in one or both eyes
  • Itching or burning sensation in one or both eyes
  • Excessive tearing
  • Discharge coming from one or both eyes
  • Swollen eyelids
  • Pink discoloration to the whites of one or both eyes
  • Increased sensitivity to light

What causes conjunctivitis?

The cause of conjunctivitis varies depending on the offending agent. There are three main categories of conjunctivitis: allergic, infectious and chemical:

Allergic Conjunctivitis

  • Allergic Conjunctivitis occurs more commonly among people who already have seasonal allergies. At some point they come into contact with a substance that triggers an allergic reaction in their eyes.
  • Giant Papillary Conjunctivitis is a type of allergic conjunctivitis caused by the chronic presence of a foreign body in the eye. This condition occurs predominantly with people who wear hard or rigid contact lenses, wear soft contact lenses that are not replaced frequently, have an exposed suture on the surface or the eye, or have a glass eye.

Infectious Conjunctivitis

  • Bacterial Conjunctivitis is an infection most often caused by staphylococcal or streptococcal bacteria from your own skin or respiratory system. Infection can also occur by transmittal from insects, physical contact with other people, poor hygiene (touching the eye with unclean hands), or by use of contaminated eye makeup and facial lotions.
  • Viral Conjunctivitis is most commonly caused by contagious viruses associated with the common cold. The primary means of contracting this is through exposure to coughing or sneezing by persons with upper respiratory tract infections. It can also occur as the virus spreads along the body’s own mucous membranes connecting lungs, throat, nose, tear ducts, and conjunctiva.
  • Ophthalmia Neonatorum is a severe form of bacterial conjunctivitis that occurs in newborn babies. This is a serious condition that could lead to permanent eye damage unless it is treated immediately. Ophthalmia neonatorum occurs when an infant is exposed to Chlamydia or gonorrhea while passing through the birth canal.

Chemical Conjunctivitis

Chemical Conjunctivitis can be caused by irritants like air pollution, chlorine in swimming pools, and exposure to noxious chemicals.

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How is conjunctivitis diagnosed?

Conjunctivitis can be diagnosed through a comprehensive eye examination. Testing, with special emphasis on evaluation of the conjunctiva and surrounding tissues, may include:

  • Patient history to determine the symptoms the patient is experiencing, when the symptoms began, and the presence of any general health or environmental conditions that may be contributing to the problem.
  • Visual acuity measurements to determine the extent to which vision may be affected.
  • Evaluation of the conjunctiva and external eye tissue using bright light and magnification.
  • Evaluation of the inner structures of the eye to ensure that no other tissues are affected by the condition.
  • Supplemental testing may include taking cultures or smears of conjunctival tissue, particularly in cases of chronic conjunctivitis or when the condition is not responding to treatment.

Using the information obtained from these tests, your optometrist can determine if you have conjunctivitis and advise you on treatment options.

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How is conjunctivitis treated?

Treatment of conjunctivitis is directed at three main goals:

  1. To increase patient comfort.
  2. To reduce or lessen the course of the infection or inflammation.
  3. To prevent the spread of the infection in contagious forms of conjunctivitis.

The appropriate treatment for conjunctivitis depends on its cause:

  • Allergic conjunctivitis – The first step should be to remove or avoid the irritant, if possible. Cool compresses and artificial tears sometimes relieve discomfort in mild cases. In more severe cases, non-steroidal anti-inflammatory medications and antihistamines may be prescribed. Cases of persistent allergic conjunctivitis may also require topical steroid eye drops.
  • Bacterial conjunctivitis – This type of conjunctivitis is usually treated with antibiotic eye drops or ointments. Improvement can occur after three or four days of treatment, but the entire course of antibiotics needs to be used to prevent recurrence.
  • Viral Conjunctivitis – There are no available drops or ointments to eradicate the virus for this type of conjunctivitis. Antibiotics will not cure a viral infection. Like a common cold, the virus just has to run its course, which may take up to two or three weeks in some cases. The symptoms can often be relieved with cool compresses and artificial tear solutions. For the worst cases, topical steroid drops may be prescribed to reduce the discomfort from inflammation, but do not shorten the course of the infection. Dr. Kaster may perform an ophthalmic iodine eye wash in the office in hopes of shortening the course of the infection. This newer treatment has not been well studied yet, therefore no conclusive evidence of the success exists. At Kaster Eye Clinic, we have had high success with this treatment thus far.
  • Chemical Conjunctivitis – Treatment for chemical conjunctivitis requires careful flushing of the eyes with saline and may require topical steroids. The more acute chemical injuries are medical emergencies, particularly alkali burns, which can lead to severe scarring, intraocular damage or even loss of the eye.

Contact Lens Wearers

Contact lens wearers may need to discontinue wearing their lenses while the condition is active. Your doctor can advise you on the need for temporary restrictions on contact lens wear.

If the conjunctivitis developed due to wearing contact lenses, your eye doctor may recommend that you switch to a different type of contact lens or disinfection solution. Your optometrist might need to alter your contact lense prescription to a type of lens that you replace more frequently to prevent the conjunctivitis from recurring.


Practicing good hygiene is the best way to control the spread of conjunctivitis. Once an infection has been diagnosed, follow these steps:

  • Don’t touch your eyes with your hands.
  • Wash your hands thoroughly and frequently.
  • Change your towel and washcloth daily, and don’t share them with others.
  • Discard eye cosmetics, particularly mascara.
  • Don’t use anyone else’s eye cosmetics or personal eye-care items.
  • Follow your eye doctor’s instructions on proper contact lens care.

You can soothe the discomfort of viral or bacterial conjunctivitis by applying warm compresses to your affected eye or eyes. To make a compress, soak a clean cloth in warm water and wring it out before applying it gently to your closed eyelids.

For allergic conjunctivitis, avoid rubbing your eyes. Instead of warm compresses, use cool compresses to soothe your eyes. Over the counter eye drops are available. Antihistamine eye drops should help to alleviate the symptoms, and lubricating eye drops help to rinse the allergen off of the surface of the eye.

See your doctor of optometry when you experience conjunctivitis to help diagnose the cause and the proper course of action.

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American Optometric Association, 8/4/10

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Diabetic Retinopathy

On August 4th, 2010, posted in: Eye & Vision Problems by

Diabetic retinopathy is a condition occurring in persons with diabetes, which causes progressive damage to the retina, the light sensitive lining at the back of the eye. It is a serious sight-threatening complication of diabetes.

Diabetes is a disease that interferes with the body’s ability to use and store sugar, which can cause many health problems. Too much sugar in the blood can cause damage throughout the body, including the eyes. Over time, diabetes affects the circulatory system of the retina.

Diabetic retinopathy is the result of damage to the tiny blood vessels that nourish the retina. They leak blood and other fluids that cause swelling of retinal tissue and clouding of vision. The condition usually affects both eyes. The longer a person has diabetes, the more likely they will develop diabetic retinopathy. If left untreated, diabetic retinopathy can cause blindness.

Symptoms of diabetic retinopathy include:

  • Seeing spots or floaters in your field of vision
  • Blurred vision
  • Having a dark or empty spot in the center of your vision
  • Difficulty seeing well at night

In patients with diabetes, prolonged periods of high blood sugar can lead to the accumulation of fluid in the lens inside the eye that controls eye focusing. This changes the curvature of the lens and results in the development of symptoms of blurred vision. The blurring of distance vision as a result of lens swelling will subside once the blood sugar levels are brought under control. Better control of blood sugar levels in patients with diabetes also slows the onset and progression of diabetic retinopathy.

Often there are no visual symptoms in the early stages of diabetic retinopathy. That is why the American Optometric Association recommends that everyone with diabetes have a comprehensive dilated eye examination once a year. Early detection and treatment can limit the potential for significant vision loss from diabetic retinopathy.

Treatment of diabetic retinopathy varies depending on the extent of the disease. It may require laser surgery to seal leaking blood vessels or to discourage new leaky blood vessels from forming. Injections of medications into the eye may be needed to decrease inflammation or stop the formation of new blood vessels. In more advanced cases, a surgical procedure to remove and replace the gel-like fluid in the back of the eye, called the vitreous, may be needed. A retinal detachment, defined as a separation of the light-receiving lining in the back of the eye, resulting from diabetic retinopathy, may also require surgical repair.

If you are a diabetic, you can help prevent or slow the development of diabetic retinopathy by taking your prescribed medication, sticking to your diet, exercising regularly, controlling high blood pressure and avoiding alcohol and smoking.

What causes diabetic retinopathy?

Diabetic retinopathy is the result of damage caused by diabetes to the small blood vessels located in the retina. Blood vessels damaged from diabetic retinopathy can cause vision loss:

  • Fluid can leak into the macula, the area of the retina which is responsible for clear central vision. Although small, the macula is the part of the retina that allows us to see colors and fine detail. The fluid causes the macula to swell, resulting in blurred vision.
  • In an attempt to improve blood circulation in the retina, new blood vessels may form on its surface. These fragile, abnormal blood vessels can leak blood into the back of the eye and block vision.

Diabetic retinopathy is classified into two types:

  1. Non-proliferative diabetic retinopathy (NPDR) is the early state of the disease in which symptoms will be mild or non-existent. In NPDR, the blood vessels in the retina are weakened causing tiny bulges called microanuerysms to protrude from their walls. The microanuerysms may leak fluid into the retina, which may lead to swelling of the macula.
  2. Proliferative diabetic retinopathy (PDR) is the more advanced form of the disease. At this stage, circulation problems cause the retina to become oxygen deprived. As a result new fragile blood vessels can begin to grow in the retina and into the vitreous, the gel-like fluid that fills the back of the eye. The new blood vessel may leak blood into the vitreous, clouding vision. Other complications of PDR include detachment of the retina due to scar tissue formation and the development of glaucoma. Glaucoma is an eye disease defined as progressive damage to the optic nerve. In cases of proliferative diabetic retinopathy, the cause of this nerve damage is due to extremely high pressure in the eye. If left untreated, proliferative diabetic retinopathy can cause severe vision loss and even blindness.

Risk factors for diabetic retinopathy include:

  • Diabetes — people with Type 1 or Type 2 diabetes are at risk for the development of diabetic retinopathy. The longer a person has diabetes, the more likely they are to develop diabetic retinopathy, particularly if the diabetes is poorly controlled.
  • Race — Hispanic and African Americans are at greater risk for developing diabetic retinopathy.
  • Medical conditions — persons with other medical conditions such as high blood pressure and high cholesterol are at greater risk.
  • Pregnancy — pregnant women face a higher risk for developing diabetes and diabetic retinopathy. If gestational diabetes develops, the patient is at much higher risk of developing diabetes as they age.

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How is diabetic retinopathy diagnosed?

Diabetic retinopathy can be diagnosed through a comprehensive eye examination. Testing, with special emphasis on evaluation of the retina and macula, may include:

  • Patient history to determine vision difficulties experienced by the patient, presence of diabetes, and other general health concerns that may be affecting vision
  • Visual acuity measurements to determine the extent to which central vision has been affected
  • Refraction to determine the need for changes in an eyeglass prescription
  • Evaluation of the ocular structures, including the evaluation of the retina through a dilated pupil
  • Measurement of the pressure within the eye


Supplemental testing may include:

  • Retinal photography or tomography to document current status of the retina
  • Fluorescein angiography to evaluate abnormal blood vessel growth

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How is diabetic retinopathy treated?

Treatment for diabetic retinopathy depends on the stage of the disease and is directed at trying to slow or stop the progression of the disease.

In the early stages of Non-proliferative Diabetic Retinopathy, treatment other than regular monitoring may not be required. Following your doctor’s advice for diet and exercise and keeping blood sugar levels well-controlled can help control the progression of the disease.

If the disease advances, leakage of fluid from blood vessels can lead to macular edema. Laser treatment (photocoagulation) is used to stop the leakage of blood and fluid into the retina. A laser beam of light can be used to create small burns in areas of the retina with abnormal blood vessels to try to seal the leaks.

When blood vessel growth is more widespread throughout the retina, as in proliferative diabetic retinopathy, a pattern of scattered laser burns is created across the retina. This causes abnormal blood vessels to shrink and disappear. With this procedure, some side vision may be lost in order to safeguard central vision.

Some bleeding into the vitreous gel may clear up on its own. However, if significant amounts of blood leak into the vitreous fluid in the eye, it will cloud vision and can prevent laser photocoagulation from being used. A surgical procedure called a vitrectomy may be used to remove the blood-filled vitreous and replace it with a clearfluid to maintain the normal shape and health of the eye.

Persons with diabetic retinopathy can suffer significant vision loss. Special low vision devices such as telescopic and microscopic lenses, hand and stand magnifiers, and video magnification systems can be prescribed to make the most of remaining vision.

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American Optometric Association, 8/4/10

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