Retinopathy of prematurity: Premature or low-birth-weight infants undergo an eye exam to determine if they have retinopathy of prematurity. An eye doctor (called an ophthalmologist) will look inside the eye to see if there are any abnormalities in the retina, macula, retinal blood vessels, and optic disc.
Diabetic retinopathy: An ophthalmologist examines inside of the eye, including the retina, with an instrument called an ophthalmoscope. A colored dye may be injected into the patient's vein before the test. The dye travels through the blood vessels, including the retinal blood vessels, making it easier for the ophthalmologist to see leaky blood vessels caused by diabetic retinopathy.
Hypertensive retinopathy: Hypertensive retinopathy is usually diagnosed during a routine eye exam because most patients do not experience any signs or symptoms of the disease. During an eye exam, an ophthalmologist uses an ophthalmoscope to look at the retina. If the patient has hypertensive retinopathy, tiny areas of the retina will appear pale or white because they are not receiving enough blood. Bleeding caused by broken blood vessels may also be visible. In some cases, the macula or optic nerve may also be swollen.
Central serous retinopathy: During an eye exam, a doctor uses an ophthalmoscope to determine if clear fluid has leaked between the layers of the retina. The fluid looks like small bubbles on the retina. If fluid is present, a positive diagnosis is made.
types and causes
Retinopathy of prematurity: Retinopathy of prematurity occurs in some premature or low-birth-weight infants. In healthy babies, the blood vessels grow outward, covering the retina. However, this process is not yet finished in infants who are born prematurely. Although the blood vessels continue to grow after birth, they grow in abnormally into the clear gel that fills the back of the eye. The abnormal blood vessels are fragile and may leak, causing bleeding in the eye.
Babies are typically at risk for retinopathy of prematurity if they are born before the end of the 29th week of pregnancy, or if the baby weighs less than 1,200 grams at birth.
In up to 85% of cases, the abnormal blood vessels disappear and the condition gets better without any treatment. However, serious cases may lead to permanent vision loss or blindness. Babies with this form of retinopathy have an increased risk of cataracts, glaucoma (increased fluid pressure inside the eyeball), crossed eyes, lazy eyes, nearsightedness, and retinal detachment. Retinal detachment occurs when the retina separates from its attachments to the back of the eyeball.
Diabetic retinopathy: About 80% of patients with type 1 or type 2 diabetes who are treated with insulin or have had diabetes for longer than 20 years develop retinopathy. This is because chronic high blood sugars levels damage sensitive blood vessels in the eye. Diabetic retinopathy is the leading cause of blindness in Americans between the ages of 20 and 64. There are two stages of diabetic retinopathy: nonproliferative and proliferative retinopathy.
Nonproliferative retinopathy, the most common type of diabetic retinopathy, is an early stage of the disease. This condition causes the blood vessels in the retina to weaken and tiny bulges (called microaneurysms or outpouchings) to develop. These microaneurysms may leak fluid and blood into the part of the retina that is responsible for sharp vision.
Proliferative retinopathy is a more advanced form of the disease. This condition occurs when abnormal blood vessels grow (proliferate) inside the retina or the optic disc. In some cases, the blood vessels may also grow inside the clear, jelly-like substance (called vitreous) in the center of the eyes. When this occurs, the blood vessels eventually leak blood into the vitreous, which clouds or impairs vision. The abnormal blood vessels may also cause irritation and lead to the formation of scar tissue. When scar tissue forms, patients have an increased risk of experiencing retinal detachment, which occurs when the layers of the retina separate. Without prompt treatment, retinal detachment may lead to permanent vision loss. Individuals may also develop a type of glaucoma, called neovascular glaucoma, which is associated with the growth of abnormal blood vessels on the colored portion of the eye (called the iris).
Either stage of diabetic retinopathy may lead to macular edema, a condition that occurs when the central part of the retina (called the macula) swells and impairs fine vision, which is necessary for reading and other detail work.
The prognoses for patients with diabetic retinopathy depends on how well blood sugar is managed, how well the condition is monitored, and how far the disease has progressed. Treatment is available to repair retinal damage and slow the progression of the disease. However, severe cases may lead to permanent blindness.
Hypertensive retinopathy: Hypertensive retinopathy occurs in some people who have high blood pressure (called hypertension). High blood pressure can cause a variety of problems with the blood vessels, including blocked retinal blood vessels, leaking blood vessels, and thickened blood vessels. All of these changes may lead to hypertensive retinopathy. Patients with hypertensive retinopathy who experience sudden and severe high blood pressure may develop swelling of the optic nerve, a condition called papilledema.
In most cases, symptoms of hypertensive retinopathy go away once the patient's blood pressure has been lowered. Patients with papilledema may also benefit from corticosteroid medications.
Central serous retinopathy: Central serous retinopathy occurs when fluid from one or more areas of the eye builds up in the membrane behind the retina, called the choroid. When the fluid leaks between the tissue layers in the retina, it causes them to separate, which may lead to poor night vision and/or blurred vision.
Central serous retinopathy occurs for unknown reasons. However, researchers believe that steroid medicines, antihistamines, antibiotics, alcohol abuse, pregnancy, nasal allergies, asthma, autoimmune disorders, and untreated high blood pressure may trigger symptoms of the disease. However, their relationship to retinopathy is not clearly understood. It has also been suggested, but not proven, that emotional stress may trigger central serous retinopathy.
For unknown reasons, central serous retinopathy is most common among males who are 20-50 years old.
In most cases, symptoms of central serous retinopathy start to go away without treatment in three to four months. For most patients, vision returns back to normal within six months. However, some individuals may experience long-term symptoms, which may include decreased contrast sensitivity, poor night vision, and distortion. It is common for this condition to return in the future.
signs and symptoms
Retinopathy of prematurity: There are no noticeable signs or symptoms of retinopathy of prematurity. Therefore, if an infant is born prematurely or has a low birth weight, an eye exam is performed to determine if he/she has the disease.
Diabetic retinopathy: Symptoms of diabetic retinopathy may go unnoticed until the condition has progressed into the later stages of the disease. Common symptoms include blurred vision, sudden loss of vision in one or both eyes, difficulty reading or seeing detailed images, and seeing flashing lights or black spots.
Hypertensive retinopathy: Patients with hypertensive (high blood pressure) retinopathy usually do not experience any signs or symptoms, which is why most cases are diagnosed after a routine eye exam. Some patients may experience blurred vision.
If the patient develops papilledema, symptoms may include headache, nausea, vomiting, and hearing a machine-like sound.
Central serous retinopathy: Symptoms of central serous retinopathy may include blurred or dim vision (which may or may not occur suddenly), blind sports, reduced visual sharpness, and seeing distorted shapes.