Table of Contents: Click on a link below to find out more.
- Cystoid Macular Edema
- Detached and Torn Retina
- Diabetic Retinopathy
- Floaters and Flashes
- Macular Degeneration
- Macular Hole
- Macular Pucker
- Retinal Vein Occlusions
Cystoid macular edema, commonly called CME, is a painless disorder which affects the retina, the light-sensitive inner lining of the eye. When this condition is present, clear fluid fills multiple cyst-like (cystoid) formations in the macula, the portion of the retina responsible for central or "straight ahead" vision. This creates macular swelling, or edema.
Although the exact causes of CME are not known, it may accompany a variety of diseases such as retinal vein occlusion, uveitis or diabetes. It most commonly occurs after cataract surgery. About three percent of those who have cataract extractions will experience decreased vision due to CME in the first year, usually from two to four months after surgery.
If the disorder appears in one eye, there is an increased risk — as high as 50% — that it will also affect the second eye. Fortunately, however, most patients recover their vision after some time.
What are the symptoms of CME?
The most common symptom of cystoid macular edema is blurred or decreased central vision (CME does not affect peripheral or side vision). There may also be painless retinal inflammation or swelling. However, the condition may be present even when no visual loss occurs. In these cases it is diagnosed by an ophthalmologist after a thorough medical eye examination, usually using a photographic test called a fluorescein angiogram
How can CME be treated?
Since many factors can lead to CME, it is not possible to say which treatment, if any, will prove effective. After the diagnosis has been made and confirmed, the ophthalmologist may attempt several kinds of treatment. Signs of retinal inflammation are usually treated with anti-inflammatory medications, including cortisone-like drugs (steroid drops, pills or local injections) or anti-inflammatory drugs like indomethacin. Diuretics such as Diamox may help to reduce the swelling in some cases.
If the vitreous (the clear, gel-like substance that fills the center of the eye) is believed to be the source of the problem, laser surgery might be recommended. Another procedure called a vitrectomy can be used to suction the vitreous out of the eye and replace it with a clear solution
In some cases, the swelling and inflammation which accompanies CME can bring on glaucoma, a disorder which often occurs due to increased pressure within the eye. When this happens, the glaucoma must be treated with appropriate medications to reduce the pressure.
A great deal of research is presently being conducted to determine the causes of cystoid macular edema. Hopefully, this research will lead to more exact prevention and treatment measures in the near future.
Why are regular eye examinations important for everyone?
Eye disease can strike at any age. Many disorders, like CME, do not always produce immediate symptoms. Since most serious vision loss is preventable if diagnosed and treated early, regular examinations by an ophthalmologist are very important.
What is the retina?
The retina is a nerve layer at the back of your eye that senses light and sends images to your brain.
An eye is like a camera. The lens in the front of the eye focuses light onto the retina. You can think of the retina as the film that lines the back of a camera.
What is a retinal detachment?
A retinal detachment occurs when the retina is pulled away from its normal position. The retina does not work when it is detached. Vision is blurred, just as a photographic image would be blurry if the film were loose inside the camera.
A retinal detachment is a very serious problem that almost always causes blindness unless it is treated.
What causes retinal detachment?
A clear gel called vitreous (vit-ree-us) fills the middle of the eye. As we get older, the vitreous may pull away from its attachment to the retina at the back of the eye.
Usually the vitreous separates from the retina without causing problems. But sometimes the vitreous pulls hard enough to tear the retina in one or more places. Fluid may pass through the retinal tear, lifting the retina off the back of the eye, much as wallpaper can peel off a wall.
The following conditions increase the chance of having a retinal detachment:
- Previous cataract surgery
- Severe injury
- Previous retinal detachment in your other eye
- Family history of retinal detachment
- Weak areas in your retina that can be seen by your ophthalmologist (Eye M.D.).
What are the warning symptoms of retinal detachment?
These early symptoms may indicate the presence of a retinal detachment:
- Flashing lights
- A shadow in the periphery of your field of vision
- A gray curtain moving across your field of vision
These symptoms do not always mean a retinal detachment is present; however, you should see your ophthalmologist as soon as possible.
Your ophthalmologist can diagnose retinal detachment during an eye examination in which he or she dilates (enlarges) the pupils of your eyes. Some retinal detachments are found during a routine eye examination.
Only after careful examination can your ophthalmologist tell whether a retinal tear or early retinal detachment is present.
The repair of retinal detachment is very successful in most cases. Some retinal detachments can be repaired in an office setting and other more severe cases are treated in the operating room as outpatient. The surgical procedure is very successful and most patients regain most of their vision.
Diabetes can affect eyesight
If you have diabetes mellitus, your body does not use and store sugar properly. High blood-sugar levels can damage blood vessels in the retina, the nerve layer at the back of the eye that senses light and helps to send images to the brain. The damage to retinal vessels is referred to as diabetic retinopathy.
Types of diabetic Retinopathy
There are two types of diabetic retinopathy: nonproliferate diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR).
NPDR, commonly known as background retinopathy, is an early stage of diabetic retinopathy. In this stage, tiny blood vessels within the retina leak blood or fluid. The leaking fluid causes the retina to swell or to form deposits called exudates.
Many people with diabetes have mild NPDR, which usually does not affect their vision. When vision is affected it is the result of macular edema (pronounced eh-DEEM-uh) and/or macular ischemia (pronounced ih-SKEE-rnee-uh).
- Macular edema is swelling or thickening of the macula, a small area in the center of the retina that allows us to see fine details clearly. The swelling is caused by fluid leaking from retinal blood vessels. It is the most common cause of visual loss in diabetes, vision loss may be mild to severe, but even in the worst cases, peripheral vision continues to function.
- Macular ischemia occurs when small blood vessels (capillaries) close. Vision blurs because the macula no longer receives sufficient blood supply to work properly.
PDR is present when abnormal new vessels (neovascularization) begin growing on the surface of the retina or optic nerve. The main cause of PDR is widespread closure of retinal blood vessels, preventing adequate blood flow. The retina responds by growing new blood vessels in an attempt to supply blood to the area where the original vessels closed.
Unfortunately, the new abnormal blood vessels do not resupply the retina with normal blood flow. The new vessels are often accompanied by scar tissue that may cause wrinkling or detachment of the retina.
PDR may cause more severe vision loss than NPDR because it can affect both central and peripheral vision.
Proliferate diabetic retinopathy causes visual loss in the following ways:
Vitreous hemorrhage: The fragile new vessels may bleed into the vitreous, a clear, gel-like substance that fills the center of the eye. If the vitreous hemorrhage is small, a person might see only a few new, dark floaters. A very large hemorrhage might block out all vision.
It may take days, months, or even years to reabsorb the blood, depending on the amount of blood present. If the eye does not clear the vitreous blood adequately within a reasonable time, vitrectomy surgery may be recommended.
Vitreous hemorrhage alone does not cause permanent vision loss. When the blood clears, vision may return to its former level unless the macula is damaged.
Traction retinal detachment: When PDR is present, scar tissue associated with neovascularization can shrink, wrinkling and pulling the retina from its normal position. Macular wrinkling can cause visual distortion. More severe vision loss can occur if the macula or large areas of the retina are detached.
Neovascular glaucoma: Occasionally, extensive retinal vessel closure will cause new, abnormal blood vessels to grow on the iris (colored part of the eye) and block the normal flow of fluid out of the eye. Pressure in the eye builds up, resulting in neovascular glaucoma, a severe eye disease that causes damage to the optic nerve.
How is diabetic retinopathy diagnosed?
A medical eye examination is the only way to detect changes inside your eye. An ophthalmologist (Eye M.D.) can often diagnose and treat serious retinopathy before you are aware of any vision problems. The ophthalmologist dilates your pupil and looks inside of the eye with an ophthalmoscope.
If your ophthalmologist finds diabetic retinopathy, he or she may order color photographs of the retina or a special test called fluorescein angiography to find out if you need treatment. In this test a dye is injected into your arm and photos of your eye are taken to detect where fluid is leaking.
Diabetic retinopathy is usually treated in the office with laser. There are occasions where intraocular injections are given in the office as well and advanced cases that require surgical treatment are repaired on an outpatient basis.
What are floaters?
You may sometimes see small specks or clouds moving in your field of vision. These are called floaters. You can often see them when looking at a plain background, like a blank wall or blue sky.
Floaters are actually tiny clumps of gel or cells inside the vitreous, the clear gel-like fluid that fills the inside of your eye.
Although the floaters appear to be in front of the eye, they are actually floating in the vitreous fluid inside the eye.
While these objects look like they are in front of your eye, they are actually floating inside it. What you see are the shadows they cast on the retina, the layer of cells lining the back of the eye that senses light and allows you to see.
Floaters can appear as different shapes such as little dots, circles, lines, clouds, or cobwebs.
What causes floaters?
When people reach middle age, the vitreous gel may start to thicken or shrink, forming clumps or strands inside the eye. The vitreous gel pulls away from the back wall of the eye, causing a posterior vitreous detachment. This is a common cause of floaters.
Posterior vitreous detachment is more common in people who:
- Are nearsighted
- Have undergone cataract operations
- Have had YAG laser surgery of the eye
- Have had inflammation inside the eye
The appearance of floaters may be alarming, especially if they develop very suddenly. You should contact your ophthalmologist (Eye M.D.) right away if you develop new floaters, especially if you are over 45 years of age.
Are floaters ever serious?
The retina can tear if the shrinking vitreous gel pulls away from the wall of the eye. This sometimes causes a small amount of bleeding in the eye that may appear as new floaters.
A torn retina is always a serious problem, since it can lead to a retinal detachment. You should see your ophthalmologist as soon as possible if:
- Even one new floater appears suddenly
- You see sudden flashes of light
If you notice other symptoms, like the loss of side vision, you should see your ophthalmologist.
Can floaters be removed?
Floaters may be a symptom of a tear in the retina, which is a serious problem, if a retinal tear is not treated, the retina may detach from the back of the eye. The only treatment for a detached retina is surgery.
Other floaters are harmless and fade over time or become less bothersome, requiring no treatment. Surgery to remove floaters is almost never required; vitamin therapy will not cause floaters to disappear.
Even if you have had floaters for years, you should schedule an eye examination with your ophthalmologist if you suddenly notice new ones.
What causes flashing lights?
When the vitreous gel rubs or pulls on the retina, you may see what look like flashing lights or lightning streaks. You may have experienced this same sensation if you have ever been hit in the eye and seen "stars."
The flashes of light can appear off and on for several weeks or months. As we grow older, it is more common to experience flashes, if you notice the sudden appearance of light flashes, you should contact your ophthalmologist immediately in case the retina has been torn.
What is macular degeneration?
Macular degeneration is a deterioration or breakdown of the macula. The macula is a small area in the retina at the back of the eye that allows you to see fine details clearly and perform activities such as reading and driving. When the macula does not function correctly, your central vision can be affected by blurriness, dark areas or distortion. Macular degeneration affects your ability to see near and far, and can make some activities—like threading a needle or reading—difficult or impossible.
Although macular degeneration reduces vision in the central part of the retina, it usually does not affect the eye's side, or peripheral, vision. For example, you could see the outline of a clock but not be able to tell what time it is.
Macular degeneration alone does not result in total blindness. Even in more advanced cases, people continue to have some useful vision and are often able to take care of themselves.
What causes macular degeneration?
Many older people develop macular degeneration as part of the body's natural aging process. There are different kinds of macular problems, but the most common is age-related macular degeneration (AMD). Exactly why it develops is not known, and no treatment has been uniformly effective. Macular degeneration is the leading cause of severe vision loss in Caucasians over 65.
The two most common types of AMD are "dry" (atrophic) and "wet" (exudative):
"Dry" macular degeneration (Atrophic)
Most people have the "dry" form of AMD. It is caused by aging and thinning of the tissues of the macula. Vision loss is usually gradual.
"Wet" macular degeneration (Exudative)
The "wet" form of macular degeneration accounts for about 10% of all AMD cases. It results when abnormal blood vessels form underneath the retina at the back of the eye. These new blood vessels leak fluid or blood and blur central vision. Vision loss may be rapid and severe.
Deposits under the retina called drusen are a common feature of macular degeneration. Drusen alone usually do not cause vision loss, but when they increase in size or number, this generally indicates an increased risk of developing advanced amd. People at risk for developing advanced AMD have significant Orusen, prominent dry AMD, or abnormal blood vessels under the macula in one eye ("wet" form).
What are the symptoms of macular degeneration?
Macular degeneration can cause different symptoms in different people. The condition may be hardly noticeable in its early stages. Sometimes only one eye loses vision while the other eye continues to see well for many years. But when both eyes are affected, the loss of central vision may be noticed more quickly.
Following are some common ways vision loss is detected:
- Words on a page look blurred
- A dark or empty area appears in the center of vision
- Straight lines look distorted, as in the following diagram:
There are several new treatments for both wet and dry macular degeneration. The wet form of macular degeneration which involves leakage of blood vessel is frequently treated with intraocular injection of anti-VEGF drugs in the office and in some cases laser. There are several types of laser treatment which are employed in different types of pathology.
The Vitreoretinal Institute has been involved as principal investigators in several drug studies for development of intraocular injection. We currently use several drugs including Lucentis, Avastin, Macugen, and Verteporfin. All of these medications have specific indications for their use.
National studies, such as AREDS, have proven that vitamin therapy can slow down the progression of dry macular degeneration. We currently recommend the AREDS formula with Lutein.
What is a macular hole?
The retina is the light sensing layer of tissue that lines the back of the eye. A specialized area of the retina, called the macula, is responsible for clear, detailed vision. The macula normally lies flat against the back of the eye, like film lining the back of a camera. A macular hole is an abnormal opening that forms at the center of the macula over a period of several weeks to months.
What are the symptoms of a macular hole?
In the early stages of hole formation, vision becomes blurred and distorted. If the hole progresses, a blind spot develops in the central vision, similar to the picture you would get if your camera film had a hole in it. Side vision remains normal, and there is no pain. It is uncommon for a macular hole to occur in both eyes.
What causes a macular hole?
Most macular holes occur in the elderly. The vitreous gel within the eye pulls on the thin tissue of the macula until it tears. The torn area gradually enlarges to form a round hole. Less common causes of macular holes include injury and long-term swelling of the macula. No specific medical problems are known to cause macular holes.
What testing might be done?
Your ophthalmologist can diagnose a macular hole by looking inside your eye with special instruments. A photographic test called flourescein angiogram may be done in order to determine the extent of the damage to the macula.
How is a macular hole treated?
Vitrectomy surgery is the only treatment that can repair a macular hole and possibly improve vision. Unfortunately, neither medication nor laser surgery is beneficial. Low vision devices may help people manage their daily activities if central vision is damaged in both eyes.
During vitrectomy surgery, the ophthalmologist uses delicate instruments inside the eye to remove the vitreous gel which is pulling on the macula. The eye is then filled with a special gas bubble which will slowly dissolve. The macular hole usually closes, and the eye slowly regains part of the lost sight. The visual outcome may depend on how long the hole was present before surgery. Vision does not return all of the way to normal.
Some of the risks of vitrectomy include:
- Retinal detachment
- High pressure in the eye
- Some loss of side vision
- Accelerated cataract formation
Do not fly in an airplane or travel up to high altitudes until the gas bubble is gone! A rapid increase in altitude can cause a dangerous rise in eye pressure.
Surgery is not necessary for everyone who has a macular hole. Some people who have normal vision in the other eye may not be troubled enough to want surgery.
Why are regular medical eye examinations important for everyone?
Eye disease can occur at any age. Many eye diseases do not cause symptoms until the disease has done damage. Since most blindness is preventable if diagnosed and treated early, regular medical examinations by an ophthalmologist are very important.
What is the macula?
The macula is the special area at the center of the retina which is responsible for clear, detailed vision. The retina is the light-sensing layer of tissue that lines the back of the eye. If your macula is damaged, your sight will be blurred.
What is macular pucker?
The macula normally lies flat against the back of the eye, like film lining the back of a camera. If macular pucker is present, the macula becomes wrinkled.This condition is also known as cellophane maculopathy, or premacular fibrosis.
What are the symptoms of macular pucker?
Vision becomes blurred and distorted, just as one would expect a picture to appear from a camera with wrinkled film. Straight lines, like doorways or telephone poles, often appear wavy.
Vision loss can vary from barely noticeable to severe. One or both eyes may be involved. For most people, vision remains stable and does not get progressively worse.
What causes macular pucker?
A thin, transparent membrane grows over the macula. When the membrane stops growing, it contracts and shrinks, wrinkling the macula. Eye conditions that may be associated with macular pucker include:
- Vitreous detachment (aging of gel inside eye)
- Torn or detached retina
- Inflammation inside eye
- Severe injury to eye
- Retinal blood vessel disorders
Macular pucker is not usually related to any medical problem outside the eye.
How is it detected?
Your ophthalmologist can detect macular pucker by examining your retina. A photographic test called a fluorescein angiogram may be done in order to tell the extent of damage to the macula.
Does macular pucker need to be treated?
Treatment is not necessary if your symptoms are mild. Eyedrops, medicines, or. laser surgery do not improve vision. Strengthening your bifocals or using a magnifier may improve near vision if both eyes are involved.
Vitrectomy surgery is the only treatment that can remove macular pucker. During this outpatient procedure your ophthalmologist uses tiny instruments to remove the membrane which is wrinkling the macula.
Usually, the macula flattens out and the symptoms slowly improve. Vision does not usually return all the way to normal. Cataracts (clouding of the lens in the eye) may develop sooner.
Complications are uncommon, but may include:
- Retinal detachment
- Recurrence of macular pucker
Surgery is not necessary for everyone who has macular pucker. Many people who have mildly blurred vision are not bothered enough to need surgery. You should consider surgery if your blurred vision is interfering with your daily activities.
Why are regular medical eye examinations important for everyone?
Eye disease can strike at any age. Many eye diseases do not cause symptoms until the disease has done damage. Since most blindness is preventable if diagnosed and treated early, regular medical examinations by an ophthalmologist are very important.
What is a retinal vein occlusion?
A retinal vein occlusion means that a vein in the retina of the eye has become blocked. The retina is the light-sensing tissue at the back of our eye. The veins drain blood out of the retina and return it to the heart.
Blockage or occlusion in the vein prevents adequate blood flow in the affected area. The walls of the vein leak blood and excess fluid into the retina.
What are the types of retinal vein occlusion?
There are two types of retinal vein occlusion:
- Central retinal vein occlusion (CRVO)
- Branch retinal vein occlusion (BRVO)
Who is at risk for a retinal vein occlusion?
Retinal vein occlusions are more common in people who have:
- Glaucoma (abnormal eye pressure)
- Age-related vascular (blood vessel) disease
- High blood pressure disorders
What are the symptoms of retinal vein occlusion?
Blurred vision is the main symptom of retinal vein occlusion. It occurs when the excess fluid leaking from the vein collects in the macula.
The macula is the central area of the retina which is responsible for our central, detailed vision. If the macula swells with excess fluid (macular edema), vision blurs.
Vein occlusions can successfully be treated with laser and intraocular injections of anti-VEGF drugs. We care currently involved in several studies comparing the results of patients treated with both laser and injections.