What is uveitis?
The uvea is the middle layer of the wall of the eye. It has three parts: the iris, the ciliary body and the choroid. Inflammation (or swelling) of any part of the uvea is called “uveitis.” Uveitis can be classified by the area involved. If the primary area involved is the iris, the condition is called “iritis”; the ciliary body, “cyclitis”, and the choroid, “choroiditis.” Uveal inflammation may also involve adjacent tissues. For example, choroiditis may spread to the retina and thus becomes a “chorioretinitis.”
In order to help diagnose what specific type of uveitis you may have, it is important for the ophthalmologist to locate the source of the inflammation. Once the source is located, the physician can best treat the condition and predict the long-term visual outcome.
The symptoms of uveitis depend upon the area that is inflamed and the duration of inflammation. Acute iritis may cause a red eye with pain and sensitivity to light. Chronic and posterior inflammation may be painless but may cause symptoms such as floaters or decreased vision. These symptoms should alert you to seek expert medical attention promptly.
How is uveitis treated?
Untreated uveal inflammation can lead to blindness. Cataract, glaucoma, retinal scarring, retinal detachment, optic nerve damage and atrophy or shrinkage of the eye are some of the potential complications of persistent uveitis. Many patients with uveitis have good vision as their disease is managed by medicines and eye drops.
A careful medical history, including family, social and sexual history, is important in the uveitis patient. Evaluation of uveitis is directed toward the diagnosis and identification of possible underlying causes of the disease. Bacteria, fungi, viruses, protozoa or other agents along with abnormalities of the immune system can cause uveitis. Testing may involve blood tests, X-rays, special ocular studies or evaluation by other skilled medical consultants beyond ophthalmology.
A full medical evaluation may reveal an inflammatory disease that has involved other organs besides the eye. Examples of this include sarcoidosis, rheumatoid arthritis and related conditions. For these types of conditions, treatment for the underlying cause of the uveitis helps all parts of the body, including the eye.
In most cases, no obvious underlying cause is found for the uveitis. Treatment then is directed to the eye inflammation alone. Treatment may include drops or injections of cortisone medication around the eye. Sometimes it may be necessary to use oral drugs that suppress inflammation, such as prednisone or cytotoxic (chemotherapeutic) agents. Treatment can be prolonged for uveitis. Therefore, close followup with an ophthalmologist is important to keep the eye functional and to detect occasional side effects from the treatments.
How common is diabetic retinopathy?
Because there are so many diabetics in India, diabetic retinopathy is becoming the leading cause of new cases of blindness among people aged 20 to 74 years. Persons with diabetes need to regularly check their blood sugar levels to be sure they are maintaining blood sugar levels that are as near normal as possible. They should also regularly see their primary healthcare provider as well as keep regular checkups with their ophthalmologist even if they are not having vision problems.
What is diabetic retinopathy?
Diabetic retinopathy is a complication of diabetes that affects the eyes by causing deterioration of the blood vessels in the retina. These weakened vessels may leak fluid or blood, develop brushlike branches, or become enlarged.
Is it safe for a woman with diabetic retinopathy to become pregnant?
Most diabetic women can have a baby without an increase in retinopathy. In some patients, however, the retinopathy might worsen enough to require laser photocoagulation. In a few cases, vision might remain decreased. It is recommended that all patients be frequently monitored during pregnancy. Generally, this means a baseline examination and visits at least every three months.
Can retinopathy be delayed by keeping blood sugar under control?
A recent national study showed that strict control of blood sugar can markedly delay the onset of diabetic retinopathy and can slow the progression of early cases. All diabetics should strive for good control of their blood sugar because some patients, even those with more advanced diabetic retinopathy, might delay the progression of the disease if their blood sugar is maintained at a reasonable level. Others, however, will see a progression of the disease even if their blood sugar is normal or near normal.
Does high blood pressure affect the eyes?
Some studies have shown the patients with high blood pressure are more likely to have retinopathy. However, since high blood pressure alone can damage the eyes, heart, kidneys and brain, patients should keep their blood pressure under control and have it monitored regularly.
Why would a person with no vision problems require laser treatment?
Patients with proliferative retinopathy might have normal vision but are still at high risk for imminent loss of vision due to hemorrhage or retinal detachment. Laser photocoagulation in these patients has been proven to be effective by the Diabetic Retinopathy Study.
Is it true that a person can lose considerable vision shortly after laser treatment?
Each case is different. In patients with advanced diabetic retinopathy, laser photocoagulation treatment is not as effective as it is in patients with early retinopathy. In many patients, the progression of retinopathy is delayed. But in others, the disease progresses despite the laser treatment or, by coincidence, at the same time as the treatment.
Should a person with diabetic retinopathy exercise?
Studies have shown that most patients with proliferative retinopathy have hemorrhages at night while they sleep. There is no convincing evidence that exercise increases the number of hemorrhages. Moreover, exercise is important not only for general well-being, but also for controlling blood sugar levels. Each patient should continue routine exercise unless he or she notices hemorrhages frequently during exercise.
If my doctor tells me that I have diabetic retinopathy, is there anything else that I should be checked for?
Yes. Patients with blurred vision from diabetic eye disease are very likely to have kidney disease and/or high blood pressure. They should be checked regularly by their primary healthcare practitioner.
Why can’t I be given a stronger prescription for glasses to compensate for my vision loss?
If the retina is damaged, stronger glasses cannot return distance vision to normal. They do provide greater magnification, but they also force a patient to hold reading material closer to the face. Most patients who have a moderate degree of vision loss opt for a hand-held magnifier in addition to normal reading glasses, allowing for a more comfortable reading distance.
Some patients might be helped greatly by low vision aids. These are special magnifying devices that enable patients to make the best use of their remaining eyesight by enlarging objects so that they can be seen with parts of the eye other than the macula. For certain patients, telescopic devices might improve distance vision. These aids are available through your own ophthalmologist
How can I prevent further vision loss from retinopathy?
There is no evidence that limiting the use of your eyes, avoiding television or bright light, taking vitamins or using sunglasses or any other devices can prevent diabetic retinopathy or its progression.
What hope does the future hold for patients with diabetic retinopathy?
Research into the basic mechanisms of retinopathy is ongoing. Doctors and scientists continue to study how the retina and choroid work and what changes occur during the aging process.
Research is also under way on means to control new blood vessel growth and blood vessel leakage. Recent studies, still awaiting confirmation, show that certain antihypertensive medications (high blood pressure drugs) may slow the development of retinopathy.
Is there any financial assistance available for people who have lost vision?
There is financial aid for people whose best-corrected vision with glasses is 20/200 or worse, or whose visual field is restricted to 10 degrees or less. They might be eligible for an additional income tax deduction as well as other financial and rehabilitative benefits to help them cope with vision loss. People with vision slightly better than 20/200 might be eligible for rehabilitative services.
What is retinal vein occlusion?
Arteries carry blood from the heart to various body parts, and veins return it. The retina has one major artery and one major vein, which is called the central retinal vein. Sometimes, branches of this vein can be blocked.
What causes retinal vein occlusion?
In most cases, an underlying causes is not found, and we never know why it happens. However, retinal vein occlusion is more common in patients with high blood pressure and arteriosclerosis.
Why does retinal vein occlusion cause decreased vision? What is the likely visual outcome?
When the vein is blocked, the circulation is greatly slowed. When this happens, the retina (the part of the eye which sees, like the film in a camera) does not work as well as it should. In addition, tiny blood vessels called capillaries leak excessive fluid into the retina, causing it to swell. This is called macular edema.
The ultimate visual outcome for patients with retinal vein occlusion cannot be predicted. About one-quarter of these patients have spontaneous improvement in vision, but in others, the vision remains decreased or even worsens.
The only known way to improve vision for patients with retinal vein occlusion is to treat the swollen retina with laser. With laser treatment, most patients have a small improvement in vision. A small minority have improvement to near normal. In many the vision is not helped at all. However, physicians normally wait a few months to see if there is a spontaneous improvement before considering laser treatment.
Are there any restrictions or precautions for patients with retinal vein occlusion?
There is no reason to limit one’s activities (such as reading, watching TV, etc.). However, when you have blurred vision in one eye for any reason, your depth perception is impaired. If this is true for you, you should be very careful doing anything that requires you to judge distances, such as using machinery, climbing ladders, pouring hot or hazardous liquids, or driving.
What is central retinal vein occlusion?
Arteries carry blood from the heart to various body parts, and veins return it. The retina has one major artery and one major vein, which is called the central retinal vein. Sometimes the vein becomes blocked. This is called central retinal vein occlusion.
What causes central retinal vein occlusion?
In most cases, there is no underlying cause and doctors do not know why it happens. However, it is more common in patients with glaucoma, high blood pressure, arteriosclerosis and diabetes.
What causes decreased vision? What is the likely visual outcome? What can be done to improve vision?
When the retinal vein is blocked, the circulation is greatly slowed. When this happens, the part of the eye which sees (like the film in a camera) does not work as well as it should.
The ultimate visual outcome cannot be predicted. A few patients, with time, have spontaneous improvement in vision. Some patients get worse. Currently, there is no known way to improve vision. Laser, eye drops and glasses will not help.
If there is no treatment for central retinal vein occlusion, why are follow-up visits necessary?
Although nothing can be done to help their vision, patients who have had a central retinal vein occlusion need to be seen at regular intervals because in about one-third of all cases, a severe form of glaucoma, called neovascular glaucoma, develops. If it looks like this is about to occur, a laser treatment is necessary. Though the laser does not improve vision, it does prevent glaucoma from developing. Of course, if there is any marked decrease in vision or if the eye becomes painful, it is important to see your doctor immediately.
Are there any restrictions or precautions for patients with central retinal vein occlusion?
There is no reason to limit one’s activities (such as reading, watching TV, etc.). However, when you have blurred vision in one eye for any reason, your depth perception is impaired. If this is true for you, you should be very careful doing anything that requires you to judge distances, such as using machinery, climbing ladders, pouring hot or hazardous liquids, or driving.
What happens during macular translocation surgery?
In order to move the retina, an operation is performed. This can be performed under local or general anesthesia. There are three basic steps to this operation.
First, the retina is intentionally detached (the wall paper lifted off the wall) by injecting fluid under the retina. Second, several stitches are placed towards the back of the eye to mildly indent the wall of the eye. (These stitches are not visible afterwards and remain permanent.) Third, an air bubble is placed into the main cavity of the eye. After surgery, patients are instructed to sit upright for 24 to 48 hours. The air bubble, in combination with the indentation of the wall of the eye, pushes the retina back into position against the back wall of the eye.
Although some variations with this technique may be used depending on the specific circumstances, these basic steps are performed to achieve macular translocation. The air bubble injected into the eye will be gradually absorbed by the body within a few days to weeks. In general, laser treatment is performed as quickly as possible after surgery (usually within one week) to the CNV.
What are the risks and benefits of macular translocation surgery?
It is impossible to predict exactly how far the retina will shift as a result of this surgery. If your doctor suggests macular translocation surgery, he or she believes there is a reasonable chance that the retina will move far enough to safely allow treatment of the CNV. Unfortunately, in a minority of patients, there is no sufficient movement of the retina.
There are risks associated with this surgery. These include infection, hemorrhage, cataract, glaucoma and retinal detachment. Although many of these problems are correctable, there is a small risk that irreversible loss of vision could develop as a result of this surgery. Macular translocation surgery does not “cure” macular degeneration. In some cases successful closure of the CNV may only be temporary and new blood vessels will grow. If this occurs, then additional laser surgery may be necessary. In some cases, additional laser surgery may not be possible. The long-term benefit of macular translocation surgery is not known. Preliminary results are encouraging, but not every patient benefits from the procedure.
There is generally only mild-to-moderate discomfort after this surgery, lasting one-to-two weeks. Some restrictions in activity beyond special positioning requirements may be required. As a result of moving the retina, some patients may experience double vision, depending on the quality of vision in the other eye. The recovery of vision after surgery is quite variable. Some patients require several weeks or even months to fully assess their visual recovery. This is often temporary. If not, in some cases it may be possible to correct visual impairments with eye glasses.