Diabetic Eye Exam

How Can Diabetes Affect Your Eyes?

People with type 1 and type 2 diabetes are at an increased risk for eye complications and peripheral neuropathy. Diabetes causes blood sugar levels to rise higher than average. High blood sugar causes several eye problems, including blurry vision, cataracts, glaucoma, and retinopathy. In fact, diabetes is the leading cause of blindness in people ages 20-74. This is why it is vital for people with diabetes to take their eye care seriously and get a comprehensive dilated eye exam at least once a year.

From 2010 to 2050, the number of Americans suffering from diabetic retinopathy is projected to nearly double, from 7.7 million to 14.6 million.

- Centers for Disease Control and Prevention (CDC)

What is Diabetic Retinopathy & How is it Diagnosed?

Diabetic retinopathy is an eye condition that can lead to vision loss and blindness in diabetics. It affects blood vessels in the retina, which is the light-sensitive tissue layer in the back of the eye, causing leakage and distorted vision. Early detection is key to avoiding permanent vision loss.

Anyone with type 1 diabetes, type 2 diabetes, or women who had gestational diabetes are at risk for developing diabetic retinopathy. The risk increases the longer someone has diabetes, and when blood sugar, blood pressure, and cholesterol levels are hard to control.

According to the American Diabetes Association, almost everyone with type 1 diabetes will eventually develop nonproliferative retinopathy. Most people with type 2 diabetes will get it as well.

The early stages of diabetic retinopathy typically do not have any symptoms. A small percentage of patients report changes in their vision, including problems reading or seeing objects in the distance. As the disease progresses, the retina’s blood vessels begin to bleed into the vitreous (gel-like fluid in the middle of the eye). When this happens, patients see dark floaters or streaks that look like spider webs. When this is left untreated, scars may form. 

Symptoms of diabetic retinopathy

Diabetic retinopathy may not have symptoms in its early stages. Symptoms that may indicate the disease is progressing include:

• Blurry vision
• Floaters, dots, strings in the field of vision 
• Seeing halos around lights
• Loss of central vision
• Loss of color vision
• Difficulty focusing 
• Fluctuating vision changes

An ophthalmologist diagnoses diabetic retinopathy with a comprehensive dilated eye exam.

What is a Diabetic Eye Exam?

Eye doctors check for diabetic retinopathy as part of a dilated eye exam or diabetic eye exam. The exam is a painless and straightforward process. If you have diabetes, it’s vital to get regular eye exams. Early treatment can stop the damage and prevent blindness associated with diabetic retinopathy. With annual eye exams, diabetic retinopathy can be diagnosed and treated before you notice any vision problems.

If your eye doctor thinks you have severe diabetic retinopathy or diabetic macular edema (DME), they might do a test known as a fluorescein angiogram. This test allows the doctor to see pictures of the blood vessels in the retina. 

What to Expect During a Diabetic Eye Exam

During the initial exam, your doctor will give you eye drops to dilate your pupil. Then, they will check your eyes for diabetic retinopathy and other eye problems, including:

• Abnormal blood vessels
• Swelling, blood, fatty deposits in the retina
• Growth of new blood vessels, scar tissue
• Bleeding in the vitreous 
• Retinal detachment
• Abnormalities in the optic nerve

The exam also includes:

• A visual acuity test to check how well you see. To do this test, your eye doctor will have you read letters off an eye chart.
• Visual field test to test your peripheral, or side vision.
• Eye muscle function test to check for any problems with the muscles surrounding the eyeball
• Pupil response test to check how light enters the eyes.
• Tonometry test to measure the amount of eye pressure. Your eye doctor will use a machine that blows a quick puff of air onto the eye to perform this test. Alternatively, the eye doctor can check your eye pressure by numbing your eyes with drops and gently placing a small probe against the eye. This is a quick and painless procedure.
• Dilation to check for issues with the inner parts of the eye.

Fluorescein angiography

After dilating your eyes, the doctor will take pictures of the insides of your eyes. Next, they will inject a special dye into an arm vein and take more photos as the dye circulates through the eye’s blood vessels. Your doctor will use the images to pinpoint closed, broken down blood vessels or blood vessels that are leaking fluid.

Diabetic Eye Exam vs. Regular Eye Exam

Whether you visit the optometrist for a regular eye exam or a diabetic eye exam, they will ask basic questions about your medical history and vision. You will also read an eye chart at both exams. Next, the doctor will give you a retinal exam using an ophthalmoscope. 

Some features of diabetic retinopathy can’t be seen during a regular eye exam and require special exams. For a better look at the inside of your eye, the doctor may use drops to dilate your pupils. They may also look at your retina with lenses and a specialized microscope called a slit lamp. The fluorescein angiography test will reveal changes in the structure and function of the retinal blood vessels.

Diabetic eye exams are a lot more specialized and complex than regular eye exams, but they are a necessary part of diabetes care. 

Cost of a Diabetic Eye Exam

The cost of a diabetic eye exam depends on many factors, including your insurance type, where you live, and the extent of your exam.

Medicare Part B covers eye exams for diabetic retinopathy once a year for diabetics.