What Are Retinal Diseases?
There are several types of disease that specifically affect the retina which is the layer of light-sensitive tissue at the back of the eye that allows you to see. Two of the most common types of retinal disease include:
Retinal Detachment is a medical emergency requiring prompt surgical treatment to preserve vision. In retinal detachment, the retina is pulled away from the underlying choroid, a thin layer of blood vessels that supplies oxygen and nutrients to the retina. Retinal detachment leaves retinal cells deprived of oxygen, so the longer the retina and choroid remain separated, the greater the risk of permanent vision loss in the affected eye. Retinal detachment is much more common in highly near-sighted eyes.
Diabetic Retinopathy is a complication of diabetes that results from damage to the blood vessels of the light-sensitive tissue at the back of the eye, or retina. Diabetic retinopathy can happen to anyone who has type 1 or type 2 diabetes, and the longer you have diabetes, the more likely you are to develop diabetic retinopathy. At first, diabetic retinopathy may cause no symptoms or only mild vision problems. Eventually, however, diabetic retinopathy can result in blindness.
What Causes Retinal Disease?
Retinal Detachment Retinal Detachment can occur as a result of trauma, advanced diabetes, an inflammatory disorder or the sagging or shrinkage of the vitreous humor, the clear gel that fills the space between the lens and the retina. Even when these conditions are not present, retinal detachment often occurs spontaneously.
Diabetic Retinopathy Diabetic Retinopathy is a complication of type 1 or type 2 diabetes. Because symptoms are unusual in the early stages, you may have diabetic retinopathy and not even know it. As the condition progresses, warning signs of diabetic retinopathy include:
- Spots floating in your vision
- Blurred vision
- Dark streaks or a red film that blocks your vision
- Poor night vision
- Vision loss
Who Should Be Checked for Retinal Disease?
Retinal Detachment often has clear warning signs. Anyone experiencing the following symptoms should schedule an eye exam as soon as possible:
- Sudden appearance of floaters or shapes such as dots, circles, lines, clouds or cobwebs that appear to “float” in front of the eye
- Sudden flashes of light in one or both eyes
- A shadow or curtain over a portion of your visual field
- Sudden blur in your vision
Diabetic Retinopathy can happen to anyone who has diabetes or those are at high risk including people who:
- Have poor control of their blood sugar level
- Have high blood pressure
- Have high cholesterol
- Are pregnant
- Are African American or Hispanic
How Do You Test for Retinal Diseases?
Your doctor may use the following tests, instruments and procedures to diagnose retinal detachment:
- Dilated Retinal Examination The doctor may use an instrument with a bright light and a special lens (ophthalmoscope) to examine the back of your eye, including the retina. The ophthalmoscope provides a highly detailed view, allowing the doctor to see any retinal holes, tears or detachments.
- Wide Field Retinal Imaging A special camera is used to visualize the back of the eye. Your doctor will likely examine both eyes even if you have symptoms in just one. If a tear is not identified at this visit, your doctor may ask you to return within a few weeks to confirm that your eye has not developed a delayed tear as a result of the same vitreous separation.
- Optical Coherence Tomography (OCT) This non-invasive diagnostic instrument is used for imaging the retina and detect problems in the eye prior to any symptoms being present to the patient. OCT allows for detection of other diseases such as hypertensive retinopathy, macular holes, and even optic nerve damage.
Your doctor will likely examine both eyes even if you have symptoms in just one. If a tear is not identified at this visit, your doctor may ask you to return within a few weeks to confirm that your eye has not developed a delayed tear as a result of the same vitreous separation.
Diabetic Retinopathy is best diagnosed with a dilated eye exam. For this exam, drops placed in your eyes widen (dilate) your pupils to allow your doctor to better view inside your eyes. The drops may cause your close vision to blur until they wear off, several hours later. During the exam, your eye doctor will look for:
- Abnormal blood vessels
- Swelling, blood, or fatty deposits in the retina
- Growth of new blood vessels and scar tissue
- Bleeding in the clear, jelly-like substance that fills the center of the eye (vitreous)
- Retinal detachment
- Abnormalities in your optic nerve
Other tests may include:
- Fluorescein angiography. With your eyes dilated, your doctor takes pictures of the inside of your eyes. Then your doctor injects a special dye into your arm and takes more pictures as the dye circulates through your eyes. Your doctor uses the images to pinpoint blood vessels that are closed, broken down, or leaking fluid.
- Optical coherence tomography. This imaging test provides cross-sectional images of the retina that show the thickness of the retina, which will help determine whether fluid has leaked into retinal tissue. Later, OCT exams can be used to monitor how treatment is working.