Diabetic Eye Examination
What is a Diabetic Eye Examination?
A diabetic eye examination is a test to check for problems of the eyes caused by diabetes.
Diabetes is a chronic metabolic disorder characterized by hyperglycemia or the presence of high sugar (glucose) levels in the blood. The level of glucose in the blood is regulated by the hormone insulin, which is produced by the pancreas. Diabetes occurs when either the pancreas does not produce sufficient insulin or when the body cannot effectively utilize the insulin it produces. Hyperglycemia is a common effect of uncontrolled diabetes and over time results in serious damage to many of the body's systems, typically the nerves and blood vessels.
An estimated 60 percent of people with diabetes are at increased risk of developing eye problems. Over time, diabetes can cause damage to your eyes that can lead to poor vision or even blindness. The sooner you diagnose diabetes-connected eye disorders, the sooner they can be treated to prevent them from getting worse. Your annual eye exam is one of the best methods to protect your eyes and help prevent blindness or future vision loss.
What Common Eye Conditions Can Be Detected with a Diabetic Eye Examination?
Your annual diabetic eye examination can help detect five common eye conditions associated with diabetes. These conditions include:
- Glaucoma: Glaucoma is an eye condition characterized by damage to the optic nerve, due to increased intraocular pressure (IOP) or internal eye pressure. The increased intraocular pressure is usually caused by the accumulation of fluid inside the eye due to its inability to drain. If left untreated, glaucoma can lead to progressive vision loss and ultimately blindness.
- Cataracts: Cataract is a condition in which the natural lens of the eye becomes cloudy over time, causing blurred vision. Cataracts usually develop as a result of aging. The natural lens of the eye is made up of protein and water and over time these proteins are altered ultimately causing gradual clouding of the lens and negatively impacting vision.
- Macular Edema: Macular edema refers to the swelling or thickening of the macula, the central part of the retina (light-receptive tissue of the eye). Macular edema occurs when fluid leaks from retinal blood vessels and accumulates in a very small area of the macula that is rich in light-receptive cells. The macula is responsible for the sharp central vision required to read, drive, sew, or recognize a face. Typical symptoms of macular edema are blurred central vision or distorted vision (straight lines may look wavy). If left untreated, this condition can cause severe vision impairment or even blindness.
- Retinopathy: Retinopathy is a complication of diabetes, characterized by progressive damage to the retina. The condition usually affects both eyes and the severity can vary, but if left untreated, it can cause blindness.
- Dry Eyes: People with diabetes are twice as likely to develop dry eyes. Dry eye is a medical condition caused by a lack of adequate tears in your eyes. As a result, your eyes are not properly lubricated, and you may feel discomfort such as a burning or stinging sensation in your eyes.
What Does Diabetic Eye Examination Involve?
Diabetic eye examinations are similar to regular eye examinations in many ways. However, during a diabetic eye examination, your ophthalmologist (eye doctor) will particularly focus on the health of your retina and the integrity of the blood vessels in your eye. Some of these tests include:
- Vision test: The vision test calculates your vision clarity for distant images and is a crucial part of every eye exam. During this test, you will be asked to recognize small and large letters on a distant eye chart. Each eye is tested separately to find out any visual discrepancies between the two eyes.
- Pupil dilation: Every diabetic eye examination necessitates pupil dilation for a clear view of your eyes’ inner structures, particularly your retina, optic nerve, and blood vessels in the back of your eye. Your ophthalmologist will dilate your pupils by administering special eye drops into your lower eyelids. The eye drops take about 30 minutes to work, and usually cause light sensitivity and temporary blurred near vision. These side effects normally subside within a few hours. In some instances, after a retinal examination, extra tests will be advised for additional examination, such as optical coherence tomography or fluorescein angiography.
- Fluorescein angiography: This examination allows the detection of damaged blood vessels in your eye. A special dye will be administered into your arm, which will travel through your bloodstream to your eyes, highlighting any damage to the blood vessels. A special camera will then capture images of any damage noted, for easy identification.
- Glaucoma test: Early diagnosis of glaucoma is important for early treatment of this vision-threatening condition. Glaucoma testing typically involves the “puff-of-air” test, in which your ophthalmologist will target a tonometer (a device that measures the pressure in your eye) towards your open eye. The tonometer delivers a puff of air and then measures your intraocular pressure based on the eye’s response to the air.
- Optical coherence tomography (OCT): This examination offers cross-section pictures of your retina to allow a clear view of the fine details and detection of any thickening or thinning of blood vessels that indicate fluid leakage.
