Retina-Vitreous Associal Medical Group

Patient Information

Our Services
The Retina
Diabetic Retinopathy
Macular Diseases
Strokes of the Retina
Floaters and Flashes
Retinal Detachment
CMV retinitis
Uveitis
Eye Surgery
The Hospital Stay

Our Services

Welcome to the Retina-Vitreous Associates Medical Group website. Our group specializes in the treatment of diseases affecting the back of the eye, specifically those of the retina, vitreous, and macula. Patients are referred by their eye doctor when a retinal problem is suspected. We care for patients with macular degeneration, diabetic retinopathy, retinal detachment, retinitis, uveitis, ocular tumors and pediatric retinal diseases.

We have five office locations. Each is equipped with state of the art diagnostic equipment and treatment facilities. Our group is active in clinical research, community education and participates in various clinical studies evaluating new treatments. We are dedicated to providing the best possible care, and can provide patient access to the most current treatment options.

What is a Retina Specialist?
Your First Appointment
Surgery and Laser Treatment
Insurance and Billing
Directions and Parking
Emergencies

What is a Retina Specialist?

A retina specialist is a medical doctor trained as an ophthalmologist, who has received additional fellowship training in diseases and surgery of the vitreous and retina. The vitreous is the jelly like substance that fills the eye. The retina is the part of the eye responsible for creating an image that is processed by the brain (see diagram). Retinal damage can cause permanent vision loss. Our retina specialists commonly treat diabetic eye disease, vitreous hemorrhage, macular degeneration, retinal detachments, uveitis, and ocular tumors.

Your First Appointment

Your first appointment with us will involve a comprehensive eye evaluation, including a detailed examination of your vitreous and retina. Your eyes will be dilated and your vision may become blurred for a brief period of time. Please set aside at least two hours for your initial consultation. If additional tests are required, your visit could be prolonged. You may wish to have someone with you to help drive you home.

Surgery and Laser Treatment

Should you need surgery, our physicians are on staff at many hospitals in the Los Angeles metropolitan area. Major locations include: Cedars-Sinai Medical Center, The Hospital of the Good Samaritan, Huntington Hospital, Little Company of Mary, Midway Hospital, San Gabriel Valley Medical center, St. Joseph's Medical Center, St. Vincent's Medical Center, and Torrance Memorial Medical Center. Most surgeries are performed as an outpatient procedure under local anesthesia, and may not require an overnight stay in the hospital. We are fully equipped to perform in-office laser procedures at all our offices.

Insurance and Billing

We accept most health insurance plans, including Medicare and Medi-Cal. Please be sure you bring insurance cards and referral forms for your first visit. If you are a member of an HMO, you must have an authorization number and/or your physician referral with you. Otherwise, your examination could be cancelled or delayed. Also expect to pay your co-payment and any deductible amounts at the time of your appointment. If special payment arrangements are necessary, please contact our office staff prior to your appointment.

Directions and Parking

Detailed maps and directions to our four office locations can be downloaded off our website from the About Us section. The maps can be customized to give you street-by-street directions from your home to our office. Your referring physician may have copies of maps to our locations. A detailed map can be provided at any of our offices. We validate parking in our North Hollywood location. The Torrance office has free patient parking. Street parking and pay parking are available in our downtown Los Angeles and Beverly Hills locations.

Emergencies

Our routine office hours are 8 AM to 5 PM Monday through Friday. In case of an eye emergency, our doctors are on call 24 hours a day, 7 days a week.

The Retina

Retina The retina is divided into two areas- the central area or "macula" and the peripheral retina. The macula has the highest concentration of retinal cells and provides the sharpest vision. We need our macula to read fine print and thread a needle. The leading cause of blindness in America, macular degeneration, causes damage to the macula.

The peripheral retina is used for peripheral vision which is critical for many activities such as driving and playing sports. A common disease of the peripheral retina is the retinal tear. This can lead to a retinal detachment and loss of peripheral and ultimately central vision as well.

Diabetic Retinopathy

Diabetic retinopathy is the leading cause of blindness in patients 20 to 74 years of age. The two forms of diabetic retinopathy result when the abnormal blood vessels of the diabetic patient begin to leak or collapse. Non-proliferative diabetic retinopathy occurs when blood vessels leak and fluid accumulates in the retina. When the leakage is severe ("clinically significant macular edema"), laser surgery can be used to reduce or eliminate the associated retinal swelling. Vision may not usually improve with the laser treatment, but if performed early enough, it may stop further vision loss.

Proliferative diabetic retinopathy results from the collapse or closure of blood vessels. The retina becomes sick were the blood vessels have closed and releases stimulants for the growth or "proliferation" of new blood vessels. These new vessels are fragile and can easily bleed causing hemorrhage in the eye and blindness. Laser surgery can drastically reduce the risk of severe vision loss in patients with proliferative diabetic retinopathy. When severe hemorrhage or scar tissue develops the microsurgical procedure termed vitrectomy may be required to restore vision. In addition, we are actively pursuing clinical research in this area as well.

Macular Diseases

Macular Degeneration

Macular degeneration (or age-related maculopathy) is the leading cause of blindness in the United States. It usually affects older patients- retirement age and above. Initial signs of macular degeneration may be picked up earlier, in the 40’s and 50’s. This is important since there is evidence that intervention with nutritional supplements and life-style changes may reduce the development of this blinding disease.

There are two forms of macular degeneration- dry and wet. The dry form is usually less severe and reading vision is often maintained. The dry forms results from degeneration of the the outer layers of the retina- the light absorbing photoreceptors and the retinal pigment epithelium (RPE). The RPE forms the blood retinal barrier between the outer retinal circulation ("choriocapillaris) and the outer retina (photoreceptors). With age, the waste products of vision accumulate beneath the RPE in little mounds called drusen. These proteinaceous and fatty-like deposits impede the flow of oxygen and nutrients and result in degeneration of both the RPE cells as well as the visual cells (photoreceptors).

In the wet form of macular degeneration, abnormal blood vessles grow from the outer retinal circulation (choroid) beneath the retinal pigment epithelium (RPE) and sometimes into the retina itself. These blood vessels can leak fluid and protein and eventually form a scar. With early diagnosis of these blood vessels, laser surgery may be used to close the blood vessels and prevent further vision loss. Fluorescein angiography and indocyanine green angiography may be used to image the abnormal blood vesselss and guide laser treatment. In addition, we have and will participate in a number of clinical studies using frontier therapies for the treatment of the most blinding form of macular degeneration.

The macula is the area of the retina that provides the best vision- for reading and fine detail. A hole in the macula can develop with Macular Holeage ("idiopathic" macular hole), trauma and in very near sighted people. Idiopathic macular holes are the most common, usually occurring in patients over the age of 50 (see picture). These hole forms from pulling by the vitreous gel on the center of the retina. Macular hole formation occurs in stages beginning with a cyst (stage 1) and ending with a full thickness hole with separation of the vitreous gel (stage 4). Reading and detail vision is ultimately lost.

Vitrectomy surgery may be used to remove the vitreous gel and close the macular hole. Fine membranes (scar tissue) are peeled from the edge of the hole and a gas bubble or oil bubble is placed in the eye to help seal the hole while it heals. When gas is used, the patient must remain face down for some time after surgery to help the hole seal. If oil is used, it must be removed in a second operation.

While most patients benefit, not all patients recover vision. Success rates vary depending on the type of hole, the duration of the hole and the stage of the hole. The other eye may become affected in 10% or so of patients. As with all surgeries, the risks, benefits and alternatives must always be considered.

Treatments For Macular Degeneration

Laser Treatments

Severe vision loss from macular degeneration occurs from the wet form of the disease where abnormal blood vessels ("membranes") grow beneath the retina. The blood vessels leak fluid, blood and protein which eventually coagulate to form a scar. Laser surgery was the first proven treatment for "wet" macular degeneration. Patients with membranes near but not beneath the center of vision may be treated with laser to destroy the abnormal blood vessels. If the membrane is beneath the center of vision ("subfoveal"), laser treatment may still be recommended if the membrane is small and the vision is poor. Unfortunately, most of these "subfoveal" membranes are large and laser treatment itself reduces vision even more. Thus, many of the new treatments that have been developed are for these "subfoveal" membranes. Problems with laser treatment include the risk of recurring blood vessels (especially in hypertensive patients) and the thermal destruction of the surrounding tissue (retina) along with the blood vessels.

Fluorescein and ICG Angiography

The abnormal blood vessels associated with macular degeneration are traditionally identified using fluorescein angiography. The dye is injected into the blood and pictures are taken with a filter to see the fluorescence filling the blood vessles. Abnormal blood vessels glow and leak. Sometimes the leakage is poorly localized or blocked by blood or pigment and the source of the abnormal blood vessels cannot be found. ICG angiography was developed to help find the source of blood vessels in such cases. The ICG dye emits infrared light which can be seen though hemorrhage and pigment. In addition, it is a larger molecule that pools in the blood vessels beneath the retina, facilitating visualization of the source of the abnormal blood vessels. When ICG angiography shows a "hot spot" away from the center of vision (fovea), then laser treatment may be effective despite the poorly defined membrane on fluorescein angiography. Unfortunately, hot spots are uncommon.

Photodynamic Therapy (PDT)

The abnormal blood vessels in the wet form of macular degeneration are traditionally treated with laser. The thermal energy of the laser destroys both the blood vessels as well as the surrounding tissue (retina). Unfortunately, the majority of patients with wet macular degeneration have abnormal blood vessels located beneath the center of vision. Thus, laser treatment will destroy the center of vision- the very thing we want to protect. Photodynamic therapy could allow selective destruction of abnormal blood vessels without damage to surrounding tissues. The PDT dye is selectively absorbed by the abnormally proliferating blood vessels. When exposed to low levels of light ("non-thermal") the dye is activated and the abnormal blood vessels are selectively destroyed. PDT therapy is currently being evaluated in clinical trials. Two drugs are being evaluated: verteporfin (Vysudine) from CIBA vision and tin ethyl etiopurpurin (SnET2) from Miravant. Initial results are promising and have shown at least temporary recovery or preservation of vision in some patients. FDA approval of the PDT trials await completion of these studies to assess the overall safety and efficacy of these new agents.

Pharmacologic Therapies

The goal is to develop agents that are selective for neovascular tissue- the new abnormal blood vessels in macular degeneration- with acceptable therapeutic indices and means of delivery. To date, no pharmacologic agents have met these criteria.

Alpha-interferon blocks vascular endothelial proliferation and migration in the laboratory. A randomized, placebo-controlled, multicenter clinical, double-blind clinical trial of alpha-interferon for subfoveal choroidal neovascular membranes showed increased visual loss in the treated group with the higher doses (6 million IU) in comparison with the control group. Thus, alpha-interferon may be ineffective or even harmful.

Isotrentioin is one of the most potent known inhibitors of blood vessel growth. This agent may act by modulating extracellular matrix components that are required for growth of abnormal blood vessels. Isotrenetoin was tested in a small phase II clinical trial- no significant beneficial effects were observed in 17 eyes with choroidal neovascular membranes.

Corticosteroids are known to inhibit blood vessel growth. Intraocular steroids were found to inhibit experimental formation of abnormal blood vessels. In an uncontrolled study, intravitreal triamcinolone produced beneficial effects in 11 of 30 eyes.

Antimetabolites are anticancer drugs that inhibit blood vessel growth. A combination steroid-antimetabolite drug (triamcinolone/5-fluorouracil) was found to be effective in inhibiting experimental choroidal neovascularization in a model of macular degeneration. No clinical studies have been pursued as of yet.

Thalidomide inhibits postreceptor signal transduction for growth factor stimulation of endothelial cells. A prospective clinical trial in patients with wet macular degeneration was halted after the drug was found to cause significant adverse side effects, such as peripheral neuropathy.

Agouron (AG3340) is a matrix metalloprotease inhibitor which blocks the extracellular matrix remodeling required for blood vessel growth. Experimentally, it decreased new blood vessel growth in the retina of mice. It has been used in clinical trials for cancer treatment. A phase II, randomized, double-masked, placebo controlled multi-center clinical trial is underway.

Macular Translocation Surgery

The goal of this surgery is to move the retina away from the abnormal blood vessels in wet macular degeneration to a new "healthy" area. The retina is either rotated around the optic nerve to a new location or it is displaced with a gas bubble. While few patients are good candidates for these procedures, significant visual recovery has been achieved in select cases.

Submacular Surgery

Submacular surgery has been used in several ways to treat macular degeneration. It was first used to wash out blood from beneath the retina when large hemorrhages occur. Tissue Plasminogen Activator (TPA) has been used with the surgery to help dissolve the clot. More recently, submacular surgery has been used to operate beneath the retina and remove the abnormal blood vessels ("membranes") that have grown. While excellent results have been found for macular degeneration associated with Presumed Ocular Histoplasmosis Syndrome (POHS), Multifocal Choroiditis with Panuveitits (MPC) and Punctate Inner Chorioditis (PIC), the results with age-related macular degeneration have been less impressive. Careful patient selection may improve success rates in age-related macular degeneration. A randomized, controlled, multi-center clinical trial of submacular surgery is currently underway.

Retinal Transplantation

Retinal transplantation has been attempted to treat patients with macular degeneration and other retinal degenerations (retinitis pigmentosa). The results have been disappointing to date. Transplant rejection is a major problem. Vision has been stabilized in a few cases for short periods of time but improvement has not been demonstrated. The use of cyclosporine and extracellular matrix may help promote graft survival. Limited clinical trials are underway.

Radiation Therapy

Radiation therapy may help the wet form of macular degeneration by inhibiting blood vessel growth. Results have been mixed with reports of improvement, no change and deterioration associated with radiation therapy. A randomized, controlled, multi-center study on radiation for age-related macular degeneration is underway.

Genetics

The genes causing some forms of macular degeneration have now been identified including Sorsby dystrophy, Best's macular Dystrophy and Stargardt's disease. Once a gene is located, a blood test may be able to determine potential risk in family members and the population. In addition, genetic therapies may be able to bypass or compensate for the abnormal gene.

Nutrition

There is growing evidence to suggest that dietary factors, particularly antioxidants and Carotenoids may reduce the risk of developing macular degeneration and may slow its progression. The Eye Disease Case-Control Study found that higher dietary intakes of Carotenoids, specifically Lutein, Zeaxanthin, and Cryptoxanthin was associated with a lower risk of age-related macular degeneration. A lower risk of AMD was also suggested for those with higher levels of vitamin C, particularly from foods. Specific vitamin supplements have now been developed taking these findings to heart. The Science Based Health supplement contains the specific Xanthonphyllic Carotenoids noted to be associated with a lower incidence of AMD. Leafy vegetables (spinach and collard greens) have a high concentration of the same carotenoids. The role of nutritional supplementation in the prevention or slowing of macular degeneration has yet to be proven.

Other Treatments

Rheotherapy to filter blood and microcurrent electrical stimulation to perhaps enhance blood flow/alter trans-membrane potentials. These controversial therapies may soon be under formal evaluation.

Macular Hole

Macular Pucker

The macula is the area of the retina that provides the best vision- for reading and fine detail. Scar tissue can form in the center of the retina creating distortion and blurring of vision. This scar tissue is called macular pucker or epiretinal membrane (see picture). Macular Pucker When the vision is only mildly affected, observation may be best. With significant distortion or blurring, however, vitreous surgery can be used to restore vision in the majority of patients. Patients generally recover half of the vision lost from the macular pucker after surgery. Vision recovery may take weeks to many months. As with all surgeries, the risks, benefits and alternatives must always be considered.

Cystoid Macular Edema

Cystoid macular edema (CME) is caused by leakage of fluid into the retina. This leakage forms cysts in the center of the retina (macula) which can be seen best with fluorescein angiography (as shown). The leakage is usually from inflammation which can result fromCystoid Macular Edema many conditions, including cataract surgery, lens implantation, retinal detachment, inflammation in the eye ("uveitis"), diabetic retinopathy and macular degeneration. The treatment depends on the cause. CME is most commonly found after cataract surgery. In these cases eye drops are first tried, including non-steroidal anti-inflammatory drugs (NSAIDS) and steroids. Thereafter a steroid injection behind the eye may be tried. Finally vitrectomy surgery may be required to remove the vitreous gel which may be pulling on the macula causing inflammation and leakage. It is important to realize that CME can result even following perfect surgery. In fact, as many as 25% or so of patients may have CME after cataract surgery. In most cases, however, the vision is not significantly affected.

Central Serous Retinopathy

Central serous retinopathy (CSR) is caused by leakage of fluid beneath the retina. This bubble of fluid or blister causes blurred vision. CSR is typically seen in young males between 20 and 40 years of age often under stress or with "Type A personality". Steroid use is also a risk factor. The condition usually resolves spontaneously over weeks to several months, but can be chronic. In select cases, laser treatment may be used to speed up recovery. Fluorescein angiography may be useful in select cases - when the diagnosis is in question, in chronic cases, and when laser treatment is considered. As shown in the example, angiogrpahy may show the classic "smoke stack" leakage.

Strokes of the Retina

Strokes of the Retina The retina can be damaged by diseases affecting the blood supply. Both arteries and veins supplying the retina may become clogged or obstructed, analagous to a stroke in the brain. This can lead to blindness by robing the retina of oxygen and nutrients. Changes in the blood vessels can be seen with diabetes, hypertension and atherosclerosis. By examining the retina we can often diagnose these diseases. Common blinding diseases involving the blood vessels are retinal artery occlusions (left) and retinal vein occlusions (right).

Floaters and Flashes

While many of us note the occasional floater, the presence of new floaters or flashes of light may signal a sight threatening event. Floaters and flashes are caused by the vitreous gell that fills the eye and lies against the retina. Normal floaters are caused by vitreous degeneration. As we age, the vitreous gel begins to degenerate into clumps of proteinaceous material which floats in the eye. With time, the gel will separate from the retina. As the gel separates, it may pull on the retina. The mechanical pull leads to the sensation of light flashes. In some cases, the pulling may cause a retinal tear or a blood vessel may tear leading to the sensation of large floaters.

A patient with new floaters or flashes should be examined promptly since these signs may indicate a retinal tear. With early diagnosis the tear may be treated with laser surgery or a freezing therapy termed cryotherapy. This will reduce the chance or the tear progressing to a retinal detachment.

Retinal Detachment

Tears and holes in the retina can lead to retinal detachment. With an opening in the retina, Retinal Detachment the fluid in the eye (vitreous) can pass through the hole, beneath the retina. A retinal detachment occurs when the retina is separated from the back of the eye from the fluid beneath it. Most detachments begin in the periphery. A shadow may be noted but central (reading) vision is initially good. With time, the detachment may progress to involve the macula and central vision will be lost. With early diagnosis and treatment, retinal detachments may be repaired by a gas bubble (pneumatic retinopexy), scleral buckle or vitrectomy surgery and excellent vision may be restored.

CMV Retinitis

Cytomegalovirus (CMV) retinitis is a potentially blinding disease that effects immunocompromised hosts, most commonly those infected with the human immunodifficiency virus (HIV). CMV retinitis affects 20-40% of HIV+ patients diagnosed with AIDS. cmv1shado.jpg (3179 bytes)Treatment options include intravenous (IV) therapy with gancyclovir, foscarnate or cidofovir. More recently, oral treatment with gancyclovir and a prodrug formulation of gancyclovir have been used and are currently being evaluated for their safety and efficacy. In addition, the gancyclovir implant has been used to deliver high local therapy for this intraocular disease. The Rretina-VitreousAssociates are national leaders in the study and treatment of CMV retinitis.

Uveitis

Uveitis Uveitis Uveitis refers to inflammation of the uveal tract of the eye: the iris, ciliary body and choroid. A variety of ocular and systemic Uveitisdiseases cause uveitis including collagen vascular diseases, viral and bacterial infections, and autoimmune diseases such as multiple sclerosis. Many cases are "idiopathic"- their cause remains unknown. Uvieits may commonly affect theUveitis retina and vitreous and the diagnosis of the cause may be difficult. The Retina-Vitreous Associates are experts in the diagnosis and management of uveitis. Members of the group have helped develop new treatments and diagnostic methods for this complex disorder.

Eye Surgery

If you are considering surgery, you should always consider the potential benefits of surgery along with the possible risks of and alternatives to surgery. While many retinal surgeries are urgent or emergent, this is not always the case. Ultimately, the decision to operate must be left up to the patient using information provided from many sources. The surgeons and staff at Retina-Vitreous Associates will help provide you with as much information as possible and take time to answer all of your questions. We will also coordinate your care with your primary medical physician when indicated as well as any referring eye care doctor.

The Hospital Stay

Most retinal surgery procedures are performed on an outpatient basis at a hospital or medical center. We have access to the best facilities in the community. We often use local anesthesia with monitored anesthesia care. This "twilight" anesthesia may facilitate more rapid recovery. In children and select adults, general anesthesia care may be used.

Most patients will go to hospital admitting the day of surgery, followed by the preoperative holding area and then the operating room. The surgery may take from 30 minutes to several hours depending on the nature of the problem.