Retina
Diabetic Retinopathy
Diabetic retinopathy is a complication of diabetes that weakens the blood vessels that supply nourishment to the retina (the light-sensitive lining in the back of the eye where vision is focused). These weak vessels can leak, swell or develop thin branches, causing a loss of vision. Changes to your vision may not be noticeable at first. But in its advanced stages, the disease can cause blurred or cloudy vision, floaters and blind spots – and, eventually, blindness. This damage is irreversible. Diabetic retinopathy is the most common diabetic eye complication and a leading cause of blindness in American adults. Macular edema, which is leaking fluid that causes blurred vision, often occurs with diabetic retinopathy.
Fortunately, diabetic retinopathy is preventable. People with diabetes are most susceptible to developing it, but your risk is reduced if you follow your prescribed diet and medications, exercise regularly, control your blood pressure, and avoid alcohol and cigarettes. Regular eye exams are an integral part of making sure your eyes are healthy. Diabetic retinopathy can be detected through a dilated eye exam.
Although damage caused by diabetic retinopathy cannot be corrected, patients diagnosed with the condition can be treated to slow its progression and prevent further vision loss. Treatment modalities include injections of certain medications, laser and surgical procedures.
Age-Related Macular Degeneration
The macula is a part of the retina in the back of the eye that ensures that our central vision is clear and sharp. Age-related macular degeneration (AMD) occurs when the vison processing cells in the center of the retina begin to weaken and die, causing vision loss. Patients may experience anything from a blurry, gray or distorted area to a blind spot in the center of vision.
AMD is the number-one cause of vision loss in the U.S. Macular degeneration doesn’t cause total blindness because it doesn’t affect the peripheral vision. Possible risk factors include genetics, age, diet, smoking and sunlight exposure. Regular eye exams are highly recommended to detect macular degeneration early and prevent permanent vision loss.
Symptoms of macular degeneration include:
- A gradual loss of ability to see objects clearly
- A gradual loss of color vision
- Distorted or blurry vision
- A dark or empty area appearing in the center of vision
There are two kinds of AMD: wet (neovascular/exudative) and dry (non-neovascular). About 10-15% of people with AMD have the wet form. “Neovascular” means “new vessels.” Accordingly, wet AMD occurs when new blood vessels grow into the retina. These new vessels are very fragile, and often leak blood and fluid between the layers of the retina. Not only does this leakage distort vision, but when the blood dries, scar tissue forms on the retina as well. This creates a dark spot in the patient’s vision.
Dry AMD is much more common than wet AMD. Patients with this type of macular degeneration do not experience new vessel growth. Instead, symptoms include thinning of the retina, loss of retinal pigment and the formation of small, round particles inside the retina called drusen. Vision loss with dry AMD is slower than with wet AMD. Treatment includes a recomendation to STOP SMOKING, and to start taking certain vitamins identified in the Age-related eye disease study (AREDS) published in 2001. AREDS 2 results will hopefully be available in 2013 and clarify whether vitamin A is helpful, as well as whether Omega 3 supplements and lutein are beneficial in reducing the progression of the disease. Ask your ophthalmologist to recommend the appropriate supplements for you based upon your medical and smoking history. Patients with wet AMD will most likely benefit from injections of certain medications into the eye.
Posterior Vitreous Detachment (Floaters)
Flashes and floaters are symptoms of the eye that commonly occur as a result of age-related changes to the vitreous gel. When we are born, the vitreous is firmly attached to the retina and is a thick, firm substance without much movement. But as we age, the vitreous becomes thinner and more watery. Vitreous debris that was once secure in the firm gel can now move around inside the eye, casting shadows on the retina. These shadows are called floaters and patients describe them in many different ways. Flashes in vision occur as a result of the vitreous tugging on the retina in the back of the eye, causing patients to see flashing lights or lightning streaks. Many people will experience floaters and flashes. Although they can occur with eye infection, eye inflammation, diabetes or after eye procedures, they frequently happen spontaneously. Flashes and floaters also may be the result of a posterior vitreous detachment (PVD). This is when the vitreous pulls forward away from the retina. Although flashes and floaters are common, especially as we age, it is important to see your doctor if you experience them as they may indicate a retinal tear or a retinal hole. Your doctor can distinguish between harmless flashes and floaters and those that may require treatment for an underlying condition.
Retinal Detachment & Retinal Holes
Retinal detachment is a serious eye condition that occurs when the retina becomes separated from the wall of the eye and its supportive underlying tissue. The retina cannot function when these two layers are detached, and without prompt treatment, permanent vision loss may occur. Retinal detachment can occur from injury to the eye or face, or from very high levels of nearsightedness.
Patients with retinal detachment may experience a blind spot, blurred vision or shadows forming in their peripheral vision. Other symptoms may include an increase in flashes and floaters. It is important to see your doctor at the first sign of symptoms in order to minimize the damage caused by this condition.
To prevent permanent vision loss, the retina must be quickly reattached. Treatment for retinal detachment can be done through surgery. Laser photocoagulation can be beneficial when a hole is identified in the retina but before the retina detaches. Laser seals off holes in the retina preventing fluid in the eye from going down the hole and detaching the retina. It is often used during surgery to repair retinal detachments as well as with pneumatic retinopexy, a procedure that creates a gas bubble within the vitreous gel and then expands to place pressure against the retina thereby helping with reattachment.
Drug Monitoring & Plaquenil
Plaquenil is a medication prescribed for connective tissue diseases such as rheumatoid arthritis and lupus. However, this drug can prove toxic to the retina and threaten the vision. Regular eye examinations are essential for those taking plaquenil because over time the retina can be damaged beyond repair and monitoring is the only way to ensure that toxicity is not occurring. The drug accumulates within the retina and can remain there for years even after it has been discontinued.
Baseline testing of the eyes is recommended before beginning treatment with Plaquenil. Once taking the medication regularly, standard exams should include a dilated assessment and visual field test. In some cases, color vision testing, retinal photography, and other retinal imaging studies are recommended as well.
