Diabetic Retinopathy (DR) is a complication of Diabetes Mellitus that left undetected and treated can lead to severe and catastrophic vision loss. All patients with diabetes should have regular eye exams and diagnostic testing in order to detect changes in the small blood vessels of the retina that may indicate the need for treatment-even if there is no vision loss! Damage to the small blood vessels in the retina that causes diabetic retinopathy is the most frequent cause of new blindness among adults aged 20-74 years old. However, with regular eye exams, early detection, diagnosis and treatment, vision loss can be prevented or halted in most instances.
Diabetic Retinopathy Risk Factors
Anyone with Diabetes (Type 1 or Type 2) is at risk of developing diabetic retinopathy. There are several important factors that can increase your risk including:
- Duration- The longer you have diabetes, the greater your risk of developing diabetic retinopathy. In Type 1 diabetic patients, 9 out of 10 patients will develop diabetic retinopathy within 10-15 years of developing diabetes and in Type 2 diabetic patients 1 of 3 has diabetic retinopathy at the time of diabetic diagnosis and 8 of 10 will have diabetic retinopathy with 15 years of diagnosis.
- Blood Sugar Control-Multiple studies have demonstrated that better the sugar control decreases the risk of diabetic retinopathy and slows the progression. For every 1% decrease in HbA1C there is a 40% reduction in the incidence of diabetic retinopathy and further less kidney and nerve disease.
- Blood Pressure Control-The better the control of your blood pressure the less likely you are to develop diabetic retinopathy and the slower the progression once developed.
- High Cholesterol-Elevated cholesterol levels can cause a worsening of diabetic retinopathy.
- Pregnancy-Pregnancy can worse diabetic retinopathy and requires careful monitoring.
- Tobacco Use
- Ethnicity-Being African-American, Hispanic or Native American can increase your risk
Stages of Diabetic Retinopathy
Diabetic Retinopathy tends to appear and progress in stages beginning with Mild Nonproliferative Retinopathy, progressing to Moderate Nonproliferative Retinopathy, further advancing to Severe Nonproliferative Retinopathy and without proper attention progressing into the most severe stage, Proliferative Retinopathy.
- Mild Nonproliferative Retinopathy-This is the earliest stage and is characterized by the presence of “dot” and “blot” hemorrhages and “microaneurysms” in the retina which can be present without any change in your vision and typically does not require treatment unless it progresses or is accompanied by Diabetic Macular Edema (DME).
- Moderate Nonproliferative Retinopathy-This is the second and slightly more severe stage with more extensive changes whereby some of the small blood vessels in the retina may become damaged enough so that they close off and diminish nutrients and oxygen to certain areas of the retina that is called ischemia.
- Severe Nonproliferative Retinopathy-This next stage is characterized by an extensive amount of retinal blood vessel damage and ischemia-a lack of oxygen-with patients at a high risk of going to the next stage of retinopathy-the proliferative stage.
- Proliferative Retinopathy-This is the most severe stage and has a significant risk of vision loss. To compensate for the lack of oxygen, areas of the retina send signals to stimulate the growth of new abnormal and fragile blood vessels in order to try and reestablish the supply of oxygen-called neovascularization. These vessels tend to break and hemorrhage into the vitreous gel and can scar and cause retinal detachment, with catastrophic vision loss. It is critical that this stage be treated as quickly as possible in order to stop the progression and preserve good vision.
Diabetic Macular Edema-Diabetic Macular Edema (DME) is a common diabetic eye problem that can cause blurry vision and even vision loss. Normally, the small blood vessels in the retina do not leak. One of the early effects of diabetes is to cause the blood vessel leakage due to weakening the inner lining of the blood vessels so that they become porous. Leakage from the retinal blood vessels may cause the center of the retina, the Macula, to actually swell, a condition called Diabetic Macular Edema. Diabetic Macular Edema can occur in any stage of Diabetic Retinopathy.
The Macula is responsible for central vision, and thus Diabetic Macular Edema can result in vision loss of varying severity. The most effective and accurate ways to observe and diagnose Diabetic Macular Edema are to perform a careful dilated examination usually accompanied by a Fluorescein Angiogram (FA) and Optical Coherence Tomography (OCT). Using the Fluorescein Angiogram, it will be possible to precisely and directly observe the severity and location of “leaky” blood vessels. By using OCT, it is possible to detect very slight thickness changes in the macula that may indicate the presence of leakage. It is important that leaking blood vessels be found as early as possible so that they can be most effectively treated. Treatment with focal or grid laser photocoagulation and and/or intravitreal injections of Vascular Endothelial Growth (VEGF) Inhibitor such as Lucentis®, Avastin® or Eylea® Injections can reduce the swelling and prevent further vision loss, but may not restore vision that has already been compromised.
The diagnosis of Diabetic Macular Edema is an indication that breakdown of the retinal blood vessels from diabetes is beginning and requires careful monitoring. In the discussion about your stage of diabetic retinopathy, we will make specific recommendations about how often you will need to return for eye examinations and the need for additional photographs, Fluorescein Angiograms or OCT scans. Please be sure to keep these appointments, as they are critical in helping you maintain your eye health and vision.
Symptoms of Diabetic Retinopathy
There are often no symptoms during the early stages of the disease nor is there any discernable pain. It is important not to wait until you experience symptoms and to have a comprehensive dilated exam at least once a year. When symptoms do occur, they range from mildly blurred central vision to complete vision loss. These changes can occur slowly almost going unnoticed or rapidly. If you do notice changes in your vision-you need to seek medical attention immediately.
- Floaters, or dark strings floating in your vision
- Blurred Vision
- Fluctuating Vision.
- Impaired Color Vision
- Dark or Empty Areas in your vision
- Vision Loss
Proliferative diabetic retinopathy frequently produces symptoms as a result of bleeding into the vitreous cavity. At first, you may notice a few specks of blood “floating” in your vision. If that occurs, see your retina specialist immediately. You may need treatment before more serious bleeding occurs. Hemorrhages tend to occur more than once, often during sleep.
On some occasions, the spots clear without treatment and your vision improves. It is likely, however, that the bleeding will reoccur and cause severe vision loss. You need to be examined by your retina specialist at the first sign of blurred vision. The close r you maintain contact with your retina specialist and the earlier you receive medical attention, the more likely that the treatment will be effective. If left untreated, proliferative retinopathy can lead to severe vision loss and even permanent blindness.
Diabetic Retinopathy Diagnosis
Routine eye exams including dilated retinal exams and retinal photos should be scheduled for all patients with diabetes on a minimum of an annual basis and more often as suggested by your eye doctor depending on the health of the retina. The most effective and accurate ways to observe and diagnose diabetic retinopathy, including Diabetic Macular Edema (DME) are to perform Optical Coherence Tomography (OCT) and Fluorescein Angiography (FA) which we will recommend again as needed to help preserve the health of the retina.
Diabetic Retinopathy Treatment
Depending on the stage and the potential for and the degree of vision loss it is possible to treat, stabilize and often reverse the effects of diabetic retinopathy. Treatment of diabetic retinopathy can use retinal laser photocoagulation treatment as well as intravitreal injections of Vascular Endothelial Growth Inhibitor (VEGF) drugs such as Lucentis® or Eylea®, or a combination of both. Optimal results require early detection ad diagnosis for treatment. Intravitreal injections of VEGF Inhibitor drugs are less destructive than retinal laser treatment and thus are more often recommended as the primary treatment for management of vision threatening complications of diabetic retinopathy. In some instances we may elect to use a corticosteroid injection or even a steroid implant, such as Ozurdex®, to help resolve DME.
Proliferative Retinopathy & Laser Treatment
Proliferative Retinopathy is treated with a retinal laser photocoagulation procedure called “Scatter Laser Treatment” or “Pan Retinal Photocoagulation”. The goal of Scatter Laser Treatment is to shrink abnormal blood vessels. We will place approximately 1,000 to 2,000 laser spots in areas of the retina away from the macula, causing the abnormal blood vessels to shrink. Since Scatter Laser Treatment requires a large number of laser spots, it is often necessary to use two or more sessions to complete the laser treatment.
Sometimes patients who have had Scatter Laser Photocoagulation will experience some loss of their side or peripheral vision, some loss of night vision and a decrease in color vision. However, Scatter Laser Treatment may be necessary to preserve the rest of your vision and stop the progression of the disease. Sometimes Scatter Laser Photocoagulation might be used in combination with intravitreal injections of Vascular Endothelial Growth (VEGF) Inhibitor such as Lucentis®, Avastin® or Eylea® Injections. When Scatter Laser Treatment with or without Vascular Endothelial Growth (VEGF) Inhibitors is unsuccessful in stopping the progression of the proliferative retinopathy and when a vitreous hemorrhage occurs and does not clear on its own, or when a retinal detachment develops, then a vitrectomy is often helpful. A vitrectomy
involves inserting instruments into the eye, and removing the vitreous gel, any blood present in the vitreous cavity, and removing the scar tissue that has grown on the surface of the retina.
Diabetic Macular Edema & Laser Treatment
Diabetic Macular Edema may treated with one of two types of retinal laser photocoagulation procedures called Focal Laser Treatment and Grid Laser Treatment. Focal Laser treatment is used to close leaking micro aneurysms in a limited area and Grid Laser treatment is used to treat a more diffuse swelling in the macula. With either type of laser treatment for Macular Edema, your doctor will place laser spots in the areas of retinal leakage surrounding the macula. These spots act to slow the leakage of fluid and reduce the amount of fluid in the retina. It is usually possible to complete these Laser Treatments in one session, however depending on the results additional treatment may be necessary. You may need to have Laser Treatment for Macular Edema more than once to control the leaking fluid. If you have Macular Edema in both eyes and require laser surgery, generally only one eye will be treated at a time. Laser treatment of Diabetic Macular Edema works to stabilize vision. In fact, laser treatment may reduce the risk of vision loss by 50 percent. In most cases, early laser treatment and/or intravitreal injections of Vascular Endothelial Growth (VEGF) Inhibitor such as Lucentis®, Avastin® or Eylea® Injections will reduce the swelling and prevent further vision loss, but may not restore vision that has already been compromised. In a small number of cases, if vision is lost, it may be improved. It is important to restate that this treatment is performed to keep vision form further declining, but does not usually result in improvement in vision already lost. This is why it is so crucial to have regular eye examinations as the goal is to diagnose vision-threatening disease before vision is compromised.