Exams and Tests
Diabetic retinopathy can be detected during an exam by an
ophthalmologist or
optometrist. An exam by your primary doctor, during
which your eyes are not dilated, is not an adequate substitute for a full exam
done by an ophthalmologist. Eye exams for people with
diabetes should include:
- Visual acuity testing. Visual acuity testing measures the eye's ability to focus and
to see details at near and far distances. It can help detect vision loss and
other problems.
- Ophthalmoscopy and slit lamp exam.
These tests allow your doctor to see the back of the eye and other structures
within the eye. They may be used to detect clouding of the lens (cataract), changes in the
retina, and other problems.
- Gonioscopy. Gonioscopy is used to find out whether the
area where fluid drains out of your eye (called the
drainage angle) is open or closed. This test is done
if your doctor thinks you may have
glaucoma, a group of eye diseases that can cause
blindness by damaging the
optic nerve.
- Tonometry.
This test measures the pressure inside the eye, which is called intraocular
pressure (IOP). It is used to help detect glaucoma. Diabetes can increase your
risk of glaucoma.
Your doctor may also perform a test called
fluorescein angiogram to check for and locate leaking
blood vessels in the retina, especially if you have symptoms, such as blurred
or distorted vision, that suggest damage to or swelling of the retina.
Fundus photography can track changes in the eye over time in people who
have diabetic retinopathy and especially in those who have been treated for it.
Fundus photography produces accurate pictures of the back of the eye (the
fundus). An eye doctor can compare photographs taken at different times to
monitor the progression of the disease and evaluate the effectiveness of
treatment.
Early Detection
Early detection and treatment of diabetic retinopathy can help prevent vision loss. For people in whom
diabetic retinopathy has not been diagnosed, the American Diabetes Association
recommends that screening be done based on the following guidelines:1
-
People with
type 1 diabetes who are age 10 and older should have
an eye exam within 3 to 5 years after diabetes is diagnosed and then every
year. If you are at low risk for vision problems, your doctor may consider
follow-up exams every 2 years.
- People with
type 2 diabetes should have an exam as soon as
diabetes is diagnosed and then every year. If you are at low risk for vision
problems, your doctor may consider follow-up exams every 2 years.
- Women with type 1 or type 2 diabetes who become pregnant should
have an exam before becoming pregnant, if possible, and then once during the
first 3 months (first trimester) of pregnancy. The eye doctor can decide
whether you need further screening for retinopathy during pregnancy based on
the results of the first-trimester exam.
Note: Pregnant women who develop
gestational diabetes are not at risk for diabetic
retinopathy and do not need to be screened for it. (But women who develop
gestational diabetes during pregnancy have a greater chance of developing type
2 diabetes later in life, which can put them at increased risk for retinopathy
and other eye problems.)
People who have diabetes are also at
increased risk for other eye diseases, including
glaucoma and
cataracts. Regular eye exams can help detect these
diseases early and prevent or delay vision loss.