Vitreo-Retinal Diseases

What are vitreo-retinal diseases?

A large variety of conditions can affect the vitreous and retina that lie on the back part of the eye that is not readily visible, such as diabetic retinopathy, macular degeneration, retinal detachments or tears, macular holes, retinopathy of prematurity, retinoblastoma, uveitis, eye cancer, flashes and floaters and retinitis pigmentosa.

What are the retina and vitreous?

The retina is an extension of the brain. It forms the interior lining of the eye and contains millions of light-sensitive nerve endings (rods and cones). The light rays that enter the eye though the cornea, then pass through the pupil, lens and vitreous ultimately focus on the retina which receives the light and transmits nerve impulses through the optic nerve to the brain, where a visual image is created.

Fluorescein angiogram of a normal retina.

Vitreous is a clear, gel-like substance that fills the cavity between the lens and the retina and serves vision by supporting the shape of the eye.

What are the macula and the fovea?

The central portion of the retina is the macula which provides central vision. The macula is composed of cones and rods. The cones allow us to see in bright light, to distinguish color, and to discern fine detail in reading and the rods are more sensitive to dim light and allow for night vision, but cannot distinguish either color or fine detail. Outside the macula, cones dwindle. The peripheral retina is made up primarily of rods, which provide peripheral vision both day and night.

In the center of the macula is the fovea, an area smaller than a pinpoint. It is composed entirely of cones. This tiny piece of the retina provides the sharpest vision --- the vision required to read. Everything we look at directly comes into focus at the fovea.

What conditions, diseases and irregularities affect the retina and vitreous?

The retina and vitreous can be affected by a large variety of conditions, including diabetic retinopathy, macular degeneration, retinal detachments or tears, macular holes, retinopathy of prematurity, flashes and floaters, retinoblastoma and retinitis pigmentosa.

What is diabetic retinopathy?

A person with diabetes is at risk for developing diabetic retinopathy among other ophthalmic disorders. Diabetic retinopathy is the leading cause of blindness in young and middle-aged adults today. The longer a person has diabetes, the greater their chance of developing diabetic retinopathy. There are two types of diabetic retinopathy:

• non-proliferative diabetic retinopathy (NPDR)
• proliferative diabetic retinopathy (PDR)

NPDR, also known as background retinopathy, is an early stage of diabetic retinopathy and occurs when the tiny blood vessels of the retina are damaged and begin to bleed or leak fluid into the retina resulting in swelling (diabetic macular edema) and the formation of deposits known as exudates. Many people with diabetes develop mild NPDR often without any visual symptoms.

Normal Retina

Non-Proliferative Diabetic Retinopathy

PDR carries the greatest risk of loss of vision and typically develops in eyes with advanced NPDR. PDR occurs when blood vessels on the retina or optic nerve become blocked consequently starving the retina of necessary nutrients. In response, the retina grows more blood vessels (neovascularization). Unfortunately these new vessels are abnormal and cannot replenish the retina with normal blood flow.

PDR may lead to any one of the following:

1. Vitreous hemorrhage - proliferating retinal blood vessels grow into the vitreous cavity and break down. Both the hemorrhaging and resultant scar tissue may interfere with vision.
2. Traditional retinal detachment - scar tissue in the vitreous and on the retina cause the retina to detach.
3. Tractional and rhegmatogenous retinal detachment - scar tissue creates a hole or tear in the retina causing it to detach.
4. Neovascular glaucoma - abnormal blood vessel growth on the iris blocks the flow of fluid out of the eye causing the pressure to increase and damaging the optic nerve.

What are the symptoms of diabetic retinopathy?

Generally, people with mild NPDR do not have any visual loss. A dilated eye exam is the only way to detect changes inside the eye before loss of vision begins. People with diabetes should have an eye examination at least once a year. More frequent exams may be necessary after diabetic retinopathy is diagnosed.

People with PDR experience a broader range of symptoms. They may:

• see dark floaters
• experience loss of central or peripheral vision
• experience visual distortions or blurriness
• experience temporary or permanent vision loss

How is diabetic retinopathy diagnosed?

Diabetic retinopathy is diagnosed by dilating the pupil and looking inside the eye with an ophthalmoscope. If an ophthalmologist discovers diabetic retinopathy, he or she may wish to order color photographs of the retina through a test called fluorescein angiography. During this test, a dye is injected into the arm and quickly travels throughout the blood system. Once the dye reaches the blood vessels of the retina, a photograph is taken of the eye. The dye allows the ophthalmologist to detect damaged blood vessels that are leaking dye.

Can diabetic retinopathy be prevented?

The most effective overall strategy for diabetic retinopathy is to prevent it as much as possible. Strict control of blood sugar levels will significantly reduce the long-term loss of vision from retinopathy. With improved diagnosis and treatment, only a small percentage of people with retinopathy develop serious vision problems.

What are the current treatment options for a person with diabetic retinopathy?

Because the earliest stages of diabetic retinopathy include inflammation, intraocular corticosteroids have been utilized with some success in selected patients. This form of treatment includes the use of a long-acting corticosteroid (triamcinolone acetonide) injected into the vitreous cavity by way of a very tiny needle under topical (drops) anesthesia. This treatment may reduce retinal swelling and improve visual acuity in patients with diabetic macular edema. However, visual recovery may be limited and the effect may last only 3 to 6 months after the treatment. Other clinical trials on corticosteroids include a sustained-release drug delivery device surgically implanted inside the eye to allow constant release of the medication. In two larger multicenter clinical trials using sustained-release steroid drug delivery devices, the Oculex Study is evaluating dexamethasone and the Bausch and Lomb Study is testing fluocinolone acetonide.

What research is currently being conducted on diabetic retinopathy?

Two new medications are currently being investigated for diabetic retinopathy. LY333531, a protein Kinase C-beta inhibitor (PKC-beta inhibitor) developed by Eli Lilly and Company, is a promising new medication for preventing the progression of diabetic retinopathy. A clinical trial on this medication does not yet have enough data to make a general recommendation to change current management strategies with laser surgery or pars plana vitrectomy. Similarly, Genetech is currently testing Anti-Vascular Endothelial Growth Factors (anti-VEGF) drugs for wet age-related macular degeneration. These anti-VEGF drugs may have future application for the treatment of diabetic retinopathy.

What advantage does Bascom Palmer Eye Institute offer patients with diabetic retinopathy?

The 30 clinical faculty members at the Bascom Palmer Eye Institute have accumulated years of clinical experience in the management of diabetic retinopathy. Drs. Harry Flynn and William Smiddy have been active in diabetic retinopathy clinical studies for more than 12 years. At the request of the American Academy of Ophthalmology, Drs. Flynn and Smiddy organized a 350-page monograph titled Diabetes and Ocular Disease: Past, Present and Future Therapies.

Dr. Harry Flynn

Diabetic patients also have a number of non-retinal abnormalities including increased rates of cataract, glaucoma, ocular muscle abnormalities, corneal diseases, and susceptibility to infection. The faculty at the Bascom Palmer Eye Institute are familiar with these potential complications and have experience in the management of these problems when they occur.

What is age-related macular degeneration?

In the western world, age-related macular degeneration (AMD) is the leading cause of legal, irreversible blindness among people 50 years of age and older.

• Dry macular degeneration (atrophic AMD) is the most common form of macular degeneration and can progress to cause severe central vision loss. This disease progresses slowly and most people usually maintain some central vision in at least one eye. The condition always starts as "dry" AMD. "Dry" AMD refers to the slow degenerative process that occurs without any formation of abnormal blood vessels. The recent Age-Related Eye Disease Study (AREDS) demonstrated that the progression of "dry" AMD could be slowed with vitamin supplementation. This study demonstrated the benefits of taking Vitamin C, Vitamin E, beta carotene, and zinc along with copper. Several vitamin preparations containing the appropriate amounts of these vitamins are currently available and we encourage patients with AMD to discuss these various vitamin preparations with their eye care specialist. Previous studies have also suggested that green leafy vegetables may be beneficial and smoking may be detrimental to patients with AMD.
• "Wet" macular degeneration (exudative or neovascular AMD) is caused by blood vessels growing under the retina in the macula. "Wet" AMD always arises from pre-existing "dry" AMD. These blood vessels leak fluid, protein, lipid and blood. Eventually, if untreated scar tissue forms under the macula and central vision is destroyed. Current treatments approved for "wet" macular degeneration include thermal laser therapy and photodynamic therapy with Visudyne®.

Normal Retina

Macular Degeneration

What are the symptoms of macular degeneration?

There is no pain associated with dry or wet AMD. The most common symptom of dry AMD is slightly blurred or fuzzy vision requiring greater illumination to see greater details. Also, an inability to recognize faces at a distance may develop.

As dry AMD progresses, a blurred spot develops in the center of vision. With time, the spot may get bigger and darker, reducing central vision. Often, when dry AMD is limited to one eye patients do not complain of visual changes because of the ability of the other healthy eye to see clearly, allowing for driving, reading, recognizing faces and seeing fine details.

Symptoms of wet AMD may be that straight lines, such as sentences on a page, appear wavy; rapid loss of central vision; and a blurred or blind spot in the center of vision.

How is macular degeneration diagnosed?

If an ophthalmologist suspects a patient of having AMD, he or she may:

• perform a visual acuity test to measure vision at a distance
• perform a dilated pupil examination to see the inside of the eye with an ophthalmoscope to check for drusen (tiny yellow deposits on the retina which are the most common early signs of AMD)
• ask the patient to look at an Amsler grid with a pattern of straight horizontal and vertical lines. To the person with AMD, the lines appear wavy, distorted or missing or a black spot may appear in the center of the grid.
• perform a fluorescein angiography. During this test, a dye is injected into the arm and quickly travels throughout the blood system. Once the dye reaches the blood vessels in the back of the eye, photographs are taken of the eye. The dye allows the ophthalmologist to detect blood vessels that are abnormal and leaking dye.

What are the current treatment options for macular degeneration?

Currently, treatments for macular degeneration are rapidly advancing and changing approximately every three months. It is anticipated that for the next three to five years, the treatment will be changing all the time. Various treatments are currently available, but most of these treatments are directed at the early stage of wet AMD. Regardless of the treatment therapy followed, patients with advanced dry macular degeneration should check the vision in each eye, one at a time, at least once a day. By staring at the central point on an amsler grid, patients can help monitor their vision regularly and can detect distortions in vision. These distortions represent the earliest stages of wet macular degeneration.

One treatment for wet AMD is thermal laser photocoagulation of the abnormal blood vessels. Only 15 percent of patients with wet AMD are eligible for this therapy. Among those treated, the blood vessels continue to grow in about 50 percent of the cases. Overall, this means that laser photocoagulation is really only helpful in about 7-8 percent of patients with wet AMD. When successfully treated, wet macular degeneration is converted back to dry macular degeneration. Over time, there will be continued vision loss, but the outcome is far better than the outcome if the wet AMD was untreated. Laser photocoagulation isn't useful for most cases of wet AMD because the blood vessels are under the center of the macula. If these blood vessels are treated with the hot laser, the center of the macula would be burned and immediate vision loss would result. This has limited the usefulness of laser photocoagulation.

Photodynamic therapy represents the new era in treatment of wet AMD. Co-developed by Novartis Ophthalmics, Inc. and QLT Inc., photodynamic therapy was investigated here at the University of Miami Miller School of Medicine's Bascom Palmer Eye Institute, as well as at other international centers of ophthalmology. The clinical trials designed to establish the therapy's effectiveness have involved more than 900 patients and have resulted in FDA approval for this therapy.

The results of the photodynamic therapy trials are a breakthrough for patients with AMD. Until now, there was no treatment that would slow the progression of this disease for the vast majority of patients with wet AMD, and some patients (10-15%) may even get visual improvement. It is estimated that more than one million people in the United States currently have wet AMD, and 200,000 new cases will be diagnosed this year. This treatment will have a tremendous impact, even though most patients with wet AMD still will not benefit from this therapy. Only about 25% of the wet AMD patients with blood vessels growing under the center of their vision will qualify for photodynamic therapy.

Visudyne therapy is based on the new platform of technology, photodynamic therapy. It entails a two-step approach designed to affect the abnormal blood vessels in wet AMD:

• First, a photosensitizing agent, a new type of drug, is injected into a vein in the arm. The drug circulates throughout the body’s blood vessels, including the abnormal vessels under the macula.
• Next, a "non-burning" laser is shined on the abnormal blood vessels, activating the drug.

Step 1
Step 2

The activated drug then selectively affects the abnormal blood vessels without damaging the surrounding retinal tissue. In some cases the therapy stops growth of the abnormal blood vessels and halts the corresponding vision loss.

Despite all these advances, we still do not have effective therapies for the vast majority of patients with dry or wet AMD. For this reason, the best option for many of our patients is to receive low vision training. Whether it is vision loss for conditions such as AMD, glaucoma or diabetes, low vision aids help patients perform normal activities of daily living and lead independent lives. To help facilitate this training, Bascom Palmer Eye Institute has a Low Vision Clinic to assess patients' remaining vision and prescribe appropriate low vision aids.

What about macular degeneration research?

There is much more that needs to be done to slow the progression of both dry and wet AMD, and even restore vision in patients with this disease. For those patients with wet AMD, there is significant hope in the very near future. Ongoing clinical research is investigating new treatment strategies using photodynamic therapy in the hope of saving much more vision in many more patients. These studies are underway and the preliminary results are very encouraging.

One of the newest strategies that holds promise is the use of new drugs that stop blood vessels in wet AMD and can cause existing blood vessels to regress. This new class of drugs is known as anti-angiogenic agents. At Bascom Palmer Eye Institute, we are currently investigating six such drugs. Three drugs are being investigated for the treatment of AMD and three drugs are being investigated for the treatment of diabetes.

The most promising anti-angiogenic drugs are being investigated in patients with wet AMD. These drugs are injected either around or into the eye. The names of these drugs are rhuFab V2 (Genentech, Inc.), Macugen (Eyetech Pharmaceuticals) and Anecortave acetate (Alcon Research Ltd.). Ophthalmologists are optimistic about the preliminary results using these drugs, but it is important to understand that these drugs are only available to patients participating in a clinical study.

For those patients who have experienced vision loss and are stable, there is a new low vision device that is undergoing clinical investigation at Bascom Palmer Eye Institute. This device is known as an intraocular miniature telescope (IMT) and is inserted into the eye at the time of cataract surgery. While this device may not help all patients with AMD, there is a very good chance that the IMT could improve the ability to read and watch television. To determine if you are a candidate, you should contact your ophthalmologist.

All of our treatments, so far, are designed to treat the vision loss associated with wet AMD and slow the progression of the disease. None of the therapies, really treat the underlying cause of AMD. While we do not yet know the cause, we don know this is a disease with a strong genetic basis. For this reason, Bascom Palmer Eye Institute is trying to find the genes responsible for AMD in the hope of someday developing a cure. To achieve this goal, we need the help of any family where one or more family member is affected with AMD. We are years away from developing a successful therapy based on genetic information, but the basis for this therapy begins with the genetic research currently underway and the help of families with AMD.

Do vitamins have an impact on the development of macular degeneration?

The National Eye Institute, one of the federal governments National Institutes of Health, sponsored a major clinical trial called the Age-Related Eye Disease Study whose results were published in the October 2001 issue of Archives of Ophthalmology. Scientists found that high levels of antioxidants and zinc may reduce the risk of losing vision in the future from age-related macular degeneration. Click here for greater details, including the dosage formulation and information for smokers.

What is a macular hole?

As people age, the vitreous gel in the eye shrinks and pulls away from the retina. Usually this occurs without consequence, however, in some cases where the vitreous is attached to the macula, it can result in the formation of a macular hole. Fluid may leak under the edges of the hole, causing a microscopic retinal detachment, which results in blurring and distortion of vision.

What are the symptoms of a macular hole?

A macular hole can cause blurred or distorted vision. A hole that goes all the way through the macula can result in significant loss of central vision.

How is a macular hole diagnosed?

An ophthalmologists who suspects a macular hole may:

• perform a visual acuity test to measure vision at a distance
• perform a dilated pupil examination to see the inside of the eye with an ophthalmoscope
• perform a fluorescein angiography. During this test, a dye is injected into the arm and quickly travels throughout the blood system. Once the dye reaches the blood vessels under the retina, a color photograph is taken of the eye. The dye allows the ophthalmologist to detect blood vessels that are leaking dye.

What are the treatment options for a patient with a macular hole?

Current treatment options for macular holes are limited to vitrectomy with an internal tamponade. The most commonly used procedure involves using a long-acting gas. During the surgery, the ophthalmologist will remove the vitreous gel from the eye so that it is no longer pulling on and distorting the macula. The vitreous gel is replaced with a bubble containing a mixture of air and gas or even silicone oil can be used. The long-acting gas acts as an internal, temporary bandage that holds the edge of the macular hole in place as it heals, though it prohibits the patient from traveling by air for at least six weeks. Under extenuating circumstances a shorter acting gas or the silicone can be used to possibly reduce or eliminate the prohibition of air travel. They physicians at Bascom Palmer believe the shorter acting gas and silicone oil do not offer quite as high success rates, but they are substantially successful. In order to maximize the effect of the repair, the patient is usually required to remain in a face down position for one week postoperatively to allow the bubble to press against the macula and seal the hole. While Bascom Palmer physicians believe that strict, continuous positioning enhances success rates, substantially high rates are obtained even in patients who are unable to maintain this position. The bubble will gradually be reabsorbed by the eye within a few weeks following surgery. As the bubble is reabsorbed, the vitreous cavity refills with a naturally produced fluid.

Currently, it is customary to peel the internal limiting membrane during surgery, as this may remove an impediment to healing the hole, and possibly even stimulate healing. This issue is controversial and studies of its efficacy are ongoing.

What advantage does Bascom Palmer offer for patients with a macular hole?

Bascom Palmer Eye Institute surgeons were among the first to perform macular hole surgery, dating back to 1991. Much of the framework of knowledge of pathogenesis, diagnostic methodology, and classification was laid at this institute. Because of this early experience, we continue to perform treatment on a high volume of patients. This allows us to make observations and conclusions regarding the most effective treatment modifications relatively rapidly.

What research in being conducted in the United States and at Bascom Palmer Eye Institute on macular holes?

Research is currently aimed at efforts to improve the 90+% success rate even more, and in a more convenient way to the patient. This is through ongoing surveillance of success in clinical series. Bascom Palmer Eye Institute conducts such series similarly to many other study centers in the country.

What are retinal detachments and retinal tears?

The retina lies flat against the inside, back wall of the eye. A retinal detachment occurs when the retina is lifted or pulled from its normal position. This can happen as a result of normal retraction of the vitreous which can tear the retina and allow fluid to seep beneath it causing a separation; a tumor; complications from other diseases; a severe blow to the head or eye and occasionally it is hereditary.

A retinal tear occurs when the vitreous shrinks, pulling a tear, or rip, in the retina. Most tears occur on the peripheral retina and have little effect on vision. However they may lead to an accumulation of fluid under the retina, which results in retinal detachment and significant vision loss.

What are the symptoms of retinal detachments?

Retinal detachment may be gradual or sudden, but it is usually accompanied by a dramatic loss of vision --- partial or complete. Many people see flashes of light, floaters or the appearance of a dark or gray curtain moving across the field of vision or a wavy or watery effect in their vision. These symptoms do no always mean the retina has detached, however, if they are present, an ophthalmologist should be consulted immediately as a detachment can cause permanent vision loss.

How are retinal detachments and tears diagnosed?

An ophthalmologist can diagnose retinal detachments and tears during a dilated pupil examination. Some can also be found during routine eye exams.

What is the treatment for retinal detachments and tears?

Retinal detachments are almost always repaired surgically. Treatment depends on the cause and extent of the retinal detachment. Most retinal tears are treated with cryo-therapy (use of a freezing probe) or laser therapy. Treatment usually prevents retinal detachment.

Alternatives include pneumatic retinopexy, scleral buckling procedure or vitrectomy with gas or silicone oil tamponade.

Pneumatic retinopexy involves injecting a gas bubble into the vitreous space. The bubble pushes the retinal tear against the back of the eye.

Scleral buckle is a tiny, flexible band that is placed around the outside of the eyeball to gently push the wall of the eye against the detached retina.

Vitrectomy is the surgical extraction of the vitreous humor and simultaneous replacement with a clear sterile solution or a dissolvable gas bubble.

Early treatment usually improves the vision of most patients with retinal detachment. Some will need more than one procedure to repair the damage, but some detachments cannot be repaired.

What is uveitis?

Uveitis is an inflammation of the uvea, the layer of the eye that lies between the retina and the sclera. The uvea contains many of the blood vessels which nourish the eye. Inflammation of the uvea can affect the cornea, the retina, the sclera, and other vital parts of the eye. Since the uvea borders many important parts of the eye, inflammation of this layer may be sight-threatening and more serious than the more common inflammations of the outside layers of the eye.

Uveitis has many different causes. It may develop following eye surgery or trauma. It may result from a virus (such as shingles, mumps, or herpes), a fungus (such as histoplasmosis), or a parasite (such as toxoplasmosis). In most cases, the cause remains unknown.

Uveitis can also be related to autoimmunity or come as a consequence of injury to the eye. Inflammation in one eye can result from a severe injury to the opposite eye (sympathetic uveitis).

What are the symptoms of uveitis?

Inflammation from uveitis may involve any of the following: the iris, the ciliary body or the choroid, therefore symptoms may be present in any of these structures. The symptoms include pain, blurred vision, redness, floaters or sensitivity to light.

How is uveitis diagnosed?

Uveitis is diagnosed through a routine eye examination using an ophthalmoscope.

What is the treatment for uveitis?

Uveitis may be treated with eyedrops, injections or oral medication. The most severe cases may require chemotherapy to suppress the immune system.

What is CMV retinitis?

Cytomegalovirus infection of the retina, known as CMV retinitis, occurs primarily in patients with acquired immunodeficiency syndrome, AIDS, though it can occur in patients with other immunosuppressive diseases. This serious infection is found in 20 - 30% of people with AIDS. Most CMV infections occur in people whose T-cell counts is dangerously low, usually under 40.

What are the symptoms of CMV retinitis?

People with CMV retinitis generally do not experience any pain but may develop floating spots in their vision, flashing lights, blind spots, blurred vision or loss of central or peripheral vision. CMV can also cause the retina to separate from the back of the eye. The disease generally starts in one eye, but often will involve both eyes. If untreated the disease can bring about retinal detachment and cause blindness in as little as two to six months.

How is CMV retinitis diagnosed?

Occasionally, the condition is detected during a routine exam when the infectious process is early and located in the peripheral retina.

What is the treatment for CMV retinitis?

Patients diagnosed with CMV retinitis are generally treated with antiviral medications, gancyclovir, foscarnet or cidofovir which can slow the progression of the disease but cannot cure it. The medications are administered intravenously, in pill form or via pellet implanted directly into the vitreous in the eye. The pill and intravenous medications allow for immediate infusion while the pellet allows for a slow, timed release of the medicine for approximately 5 to 8 months.

Nearly 100% of patients will eventually have a relapse of CMV retinitis, despite the best attempts at control.

What is retinopathy of prematurity?

Retinopathy of prematurity (ROP) is the leading cause of childhood blindness in developed countries. Bascom Palmer physicians and scientists have earned international recognition for pioneering research into the cause and prevention of ROP. Studies conducted in cooperation with community neonatologists and ophthalmologists have led the way to a new understanding of ROP and to the identification of its potential victims.

Premature or low birth weight babies often need to receive oxygen until their immature lungs develop. Today, physicians know that exposure to high levels of oxygen over extended periods of time can trigger the disease in infants, causing the retina's tiny developing blood vessels to grow wildly and produce scars. In some children, the retina is able to recover and damage is moderate. However, in severe cases, there is retinal detachment and, ultimately, blindness.

What is the current treatment for retinopathy of prematurity?

Bascom Palmer Eye Institute has an established ROP protocol for premature babies who meet specific criteria (including birth weight). The ROP team conducts an extensive screening examination, including Retcam photography, ultrasound, and laser therapy to treat the rapid growth of blood vessels. In some cases, this treatment is quite successful.

In a multi-center, collaborative four-year study conducted at Bascom Palmer, physicians identified the level of oxygen dangerous to an infant's eyes. More importantly, the study revealed that a baby's exposure to oxygen in the first week after birth is less critical than exposure in the weeks that follow. In other words, low-birth-weight babies who remain on oxygen during the second through the fourth week are at greater risk of developing ROP and of developing its most severe form.

It is anticipated that the results of this study will generate new technology that more accurately monitors and controls the amount of oxygen that a baby's body absorbs while on life support. Because life support is often critical in preventing brain damage and death, the need for a solution, as soon as possible, is clear.

What is retinoblastoma?

Retinoblastoma (RB) is a rare form of cancer affecting the light-sensitive retinal cells that enable sight. Although the disease is very rare, it is the most common ocular malignancy in children and the third most common cancer to affect children --- occurring in one out of every 15,000 births. In the United States, 250 to 350 new cases are diagnosed each year --- 90 percent of which occur in children under five years of age.

There are two types; one is hereditary and affects both eyes (occurs in 10% of cases) and the other type is non-hereditary and affects only one eye, carrying no increased risk of a second tumor. Although the cancer is genetically determined, only 6 percent of newly diagnosed RB patients are found to have a positive family history of the disease. Forty percent of all children have a lifelong cancer risk from abnormality in the RB gene located in chromosome 13. In all cases, genetic counseling is important for children with a germ-line mutation.

What are the current treatment options for retinoblastoma?

Early detection of RB greatly enhances the possibility of a cure and the preservation of the greatest amount of vision, though it can lead to vision loss of one or both eyes. The treatment of RB depends on the size and location of the tumor and whether one or both eyes are involved. With earlier detection and improved treatments, the prognosis for vision and life for RB patients has improved significantly in the past twenty years. However, because the disease is so rare, many pediatricians and primary care providers may not recognize the early signs, and parents rarely notice the subtle changes that may identify a tumor in their child's eyes. Left untreated, RB tumor nodules grow rapidly, expanding to fill the eye and extending along the optic nerve to the brain, ultimately causing death.

What about RB research?

Bascom Palmer Eye Institute is recognized as one of the foremost eye centers involved in national studies to evaluate and coordinate newly developed theories and therapies, including RB, related to ocular cancer. We are one of four international institutions coordinating the International Clinical Trial on Chemotherapy for Retinoblastoma, which is funded by the National Cancer Institute.

Dr. Timothy Murray, Professor of Ophthalmology and retina specialist at Bascom Palmer, and his colleagues also have participated in clinical studies on a new focal chemotherapy for eye cancer. "I'm proud to have reported and discussed our work on focal chemotherapy, and the work of others, at the annual meeting of the Academy of Ophthalmology," he says. "We're very excited about our findings thus far, and I'm looking forward to translating our laboratory results to patients as soon as possible. Our work on this project during the last four years has changed how we and others treat children. Clinical studies are not just about how to treat patients better, they also help us develop new therapies for the next generation."

In another area of developing research, Jean-Marie Parel, Ph.D., Bascom Palmer's internationally renowned Director of Ophthalmic Biophysics, is pursuing two major innovations in eye cancer treatment. The first is a laser that is custom-designed to fight eye cancer; the second is a new delivery system for chemotherapy treatments. Dr. Parel and his team of ocular biophysicists are working closely with Dr. Murray on the application of these new technologies for treating and curing patients with eye cancer.

Over the last decade there has been a revolution in ophthalmic treatment for ocular tumors. Bascom Palmer Eye Institute has been a leader in the application and study of new treatments. In addition to our comprehensive clinical and research team, we have the advantage of access to resources in the University of Miami's Sylvester Comprehensive Cancer Center, Courtelis Center for Psychosocial Oncology and Jackson Memorial Hospital. Given this comprehensive integration of in-depth expertise, basic and clinical research, and patient-oriented care, Bascom Palmer Eye Institute will continue to lead the world in the development and application of ocular cancer care.

What is retinitis pigmentosa?

Retinitis pigmentosa (RP) is a group of diseases which tend to run in families that cause progressive degeneration of the retina in both eyes. It progresses from night blindness to loss of the peripheral visual field. The signs of the disease usually present in youth or young adulthood, but can occur at any age. Over many years, RP then progresses to tunnel vision and finally blindness.

What are the symptoms of retinitis pigmentosa?

The symptoms of RP vary and can include night blindness in early stages of the disease. Night blindness refers to an inability to adjust vision to the darkness or a very slow adjustment. During later stages, the next symptom to appear is a gradual loss of peripheral or side vision so that the person can only see through a small area of the eye and only straight ahead, this is also referred to as tunnel vision.

What are the current treatment options for retinitis pigmentosa?

Researchers at Bascom Palmer’s Retinal Degeneration Center are conducting research into the genetic causes and possible treatment options for RP. Unfortunately, there is currently no effective treatment leading to a cure for retinitis pigmentosa. Occasionally, some treatments can slow the degeneration of vision or preserve vision for a longer period of time, these include vitamin therapies. Many patients with progressive RP may continue to perform daily living tasks with the use of low vision aids, telescopic lenses to improve distance vision, magnifying lenses, field enhancers and others. Bascom Palmer Eye Institute has a Low Vision Clinic to assess patients’ remaining vision, prescribe appropriate low vision aids and train patients in their proper use for maximum benefit.

What are flashes and floaters?

Flashes are a brief perception of light in the field of vision and floaters are bits of optical debris usually in the vitreous that are interpreted as threats or small spots or circles.

As a person ages, the vitreous thins and may separate from the retina, causing a posterior vitreous detachment, a common, typically harmless condition. When posterior vitreous detachment occurs, the detached vitreous can pull on the retina accompanied by flashes of light or tiny bits of vitreous that cast shadows on the retina creating floaters.

What are the symptoms of floaters and flashes?

Floaters can appear to be black spots or small circles, cob webs that may move or remain in one place. Flashes take on the appearance of bright flashes of light. More serious symptoms includes a sudden decrease of vision accompanied by floaters and flashes; a curtain that obstructs the field of vision; or a sudden increase in floaters.

How are floaters and flashes diagnosed?

Your ophthalmologist will exam your retina through dilated pupils with an ophthalmoscope.

What are the current treatment options for floaters and flashes?

In most cases of posterior vitreous detachment, surgery is not recommended and the patient can learn to ignore the floaters and they usually become less bothersome over several weeks. In more severe cases, vitrectomy may be considered only if vision is significantly compromised.

Who are the Vitreo-Retinal Specialists at Bascom Palmer Eye Institute?

The vitreo-retinal ophthalmologists at Bascom Palmer Eye Institute have made significant contributions to the advancement of vitreo-retinal care for more than 40 years, they include:

• Having developed more than 200 surgical instruments and devices, such as the vitreous infusion suction cutter (VISC), the "rare earth" intraocular foreign body magnet and the canulated extrusion needle
• Pioneering vitreous surgery
• Pioneering the use of flourescien angiography for the diagnosis of retinal and macular disease
• Establishing the value of laser photocoagulation as a useful treatment for early diabetic retinopathy, diabetic retinopathy, macular degeneration, and branch vein occlusion.
• Establishing the value of vitrectomy as treatment for infectious diseases of the eye and perforation injuries to the globe
• Popularizing the use of intraocular gas for the management of selective complex retinal detachments
• Publishing the use of intraocular antibiotics administered by injection into the eye
• Reporting the value of silicone oil for retinal detachments
• Reporting the results for vitrectomy for macular holes

The vitreo-retinal specialists at Bascom Palmer Eye Institute:

Thomas Albini, M.D.
Audina Berrocol, M.D.
John G. Clarkson, M.D.
Janet Davis, M.D.
Sander Dubovy, M.D.
Yale L. Fisher, M.D.
Harry Flynn, M.D.
Jeffrey L. Goldberg, M.D., Ph.D.
Jaclyn L. Kovach, M.D.
Geeta Lalwani, M.D.
Wen-Hsiang Lee, M.D.
Andrew A. Moshfeghi, M.D.
Timothy G. Murray, M.D., M.B.A., F.A.C.S.
Philip J. Rosenfeld, M.D., Ph.D.
Stephen Schwartz, M.D., M.B.A.
William Smiddy, M.D.

Other Vitreo-Retinal Resources

AMD Alliance International
American Academy of Ophthalmology
Eye Resources on the Internet
Foundation Fighting Blindness
Macular Degeneration Partnership
National Eye Institute
Prevent Blindness America
Research to Prevent Blindness

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