Diabetic Eye Exam and Diabetic Retinopathy
Diabetic is not only a disease, it's a epidemic.
"More than 100 million U.S. adults are now living with diabetes or prediabetes, according to a new report released today by the Centers for Disease Control and Prevention (CDC). The report finds that as of 2015, 30.3 million Americans – 9.4 percent of the U.S. population –have diabetes. Another 84.1 million have prediabetes, a condition that if not treated often leads to type 2 diabetes within five years."
What is Diabetes?
Diabetes is a metabolic a disease in which the body’s ability to produce or respond to the hormone insulin is impaired. That means that high levels of glucose are circulating in the body. Glucose is toxic to certain cells and specifically is toxic to the pericytes which are useful to normal blood vessel physiology
When those cells die, the blood vessels become leaky triggering a cascade of events that affect nearly every system in the body.
Diabetes tends to affect small vessels first. Organs very reliant on small vessels are the kidney and the eye, which is why those two organs are some of the first to suffer from diabetes.
How does diabetes affect the eye?
Diabetes is going to affect the eye in two main fashions:
Changes in refractive error (increase or decrease of glasses power needed, when blood sugar is high or goes lower)
Diabetic Eye Disease
Diabetes Affects primary the back of the eye or the retina. The vessels located in the retina start leaking, forming micro-aneurysms.
There are 2 forms of diabetic eye disease or diabetic retinopathy:
Non Proliferative Diabetic Retinopathy (NPDR)
At that stage, small amount of hemorrhages form in different shapes: pin point, dot hemes, blot hemes which are a bit larger, eventually flamed shape hemes. Most patients who have Non Proliferative Diabetic Retinopathy (NPDR) are absolutely asymptomatic. Those small hemorrhages tend to not affect vision. Patients become symptomatic when they develop macular edema, which is an accumulation of fluid in the central part of the eye. This will result in changes, loss of central vision.
About 20% of diabetics are diagnosed during a routine eye exam ,where their optometrist, upon dilated fundus examination sees diabetic eye disease. The patient is then referred to a primary care doctor to confirm the diagnosis via blood work, checking fasting blood glucose levels. Many diabetic patients are asymptomatic at the beginning of the disease and can go years without being diagnosed, sustaining damage to their body. Every year, it is recommended you get a routine eye exam and a physical exam. Our office in Miami is ready to welcome you for a routine eye exam or a diabetic eye exam if you are already a known diabetes patient.
If Significant Non Proliferative Diabetic Retinopathy (NPDR) or any level of Macular Edema is seen during your routine eye exam, you will be referred to a retinal specialist for further evaluation. The specialist will obtain a Fluorescein Angiography (FA) to assess permeability and leakage of your retinal blood vessels. An OCT can be done to check for macular edema. In recent years, new technology became available: an exam know as an OCTA can be done. This Ocular Coherence Tomography with Angiography can be performed. Without injecting any dies, this OCTA allows for visualization of retinal blood vessels integrity.
If Diabetic Macular Edema is seen, your eye doctor may elect to inject some medicine inside the eye to prevent further damage and for you to regain vision. Those medicine can be Anti-VEGF (See our page on macular degeneration) or steroids.
Proliferative Diabetic Retinopathy (PDR)
Later in the disease, once blood leaks and not enough oxygen arrives to the retina, new blood vessels or neo-vessels are formed. This is natural way for the body to fight the lack of oxygen. Unfortunately those blood vessels are incompletely formed, have very weak membranes and sooner than later rupture leading to vitreous or retinal hemorrhaging. In that situation there is more blood present resulting in significant visual loss. If nothing is done, scar tissue can form and pull on the retina triggering a retinal detachment. At this stage, it is very difficult to save the eye and visual function.
With Diabetes, prevention is key. Do see your general physician every year for routine blood work. If early signs of diabetes are seen, he may elect to start you on diabetes medicine to prevent or slow down complications.
What is a diabetic eye exam?
In our optometry North Miami office, when we see a patient with diabetes, a careful history is taken. One of our eye doctors will ask you the nature of your diabetes (Type 1 or type 2), the duration of the disease, your fasting blood glucose level for that day as well as your hemoglobin A1C, which indicates your average blood glucose for the 3 months prior.
An exam is then perform with a careful dilated eye examination looking for any signs of diabetic retinopathy. You may ask for a report from your eye doctor to your primary care, the latter needing to know the results of your diabetic eye exam.
If no signs of diabetic retinopathy are seen, the diabetic eye exam should be repeated yearly.
If the level of diabetic retinopathy warrants it, you will be referred to a retinal specialist, per EDTRS guidelines.