Diabetic Eye Disease
Diabetes mellitus is one of the leading causes of irreversible blindness worldwide, and, it is the most common cause of blindness in people younger than 65 years of age.
In addition to being a leading cause of blindness, diabetic eye disease encompasses a wide range of problems that can affect the eyes.
Diabetes mellitus may cause a reversible, temporary blurring of the vision, or it can cause a severe, permanent loss of vision.
Diabetes mellitus increases the risk of developing cataracts and glaucoma.
Some people may not even realize they have had diabetes mellitus for several years until they begin to experience problems with their eyes or vision. Severe diabetic eye disease most commonly develops in people who have had diabetes mellitus for many years and who have had little or poor control of their blood sugars over that period of time.
Diabetic Eye Disease Causes
Over many years, high blood sugar and other abnormalities in metabolism found in people with diabetes mellitus may damage the blood vessels in the body. This damage to the blood vessels leads to poor circulation of the blood to various parts of the body. Since the function of the blood is to carry oxygen and other nutrients, this poor circulation causes decreased oxygen delivery to tissues in different parts of the body and subsequent damage to those tissues.
Some of the most sensitive tissues to decreased blood flow and oxygen delivery include the brain, heart, kidneys, and the eyes. Lack of adequate oxygen delivery to these areas causes strokes, heart attacks, kidney failure, and vision loss.
Diabetic eye disease can cause a wide range of problems that affect the eyes, in particular the retina, the lens, and the trabecular meshwork.
The primary part of the eye affected by diabetes mellitus is the Retina.
The retina can be thought of as the film in a camera. If the film in a camera is faulty, the resulting picture will be blurry. In a similar manner, if the retina of the eye is swollen, wrinkled, or otherwise structurally damaged, the vision in that eye will be blurry. Depending on the type, location, and extent of damage in the retina, the change in vision will range from minimal to severe and be temporary or permanent.
In people with diabetes mellitus, changes in the walls of the small blood vessels in the retina are caused by blood sugar abnormalities. These small blood vessels may begin to "balloon," forming what are called micro-aneurysms, as well as leak fluid (called edema) and blood (called dot and blot hemorrhages) into the retina. This process is called background diabetic retinopathy or non-proliferative diabetic retinopathy. If fluid accumulates in the central part of the retina (called the macula) and causes swelling there, the process is called diabetic macular edema.
As a response to decreased oxygen delivery to the retina, new blood vessels may begin to grow, a process called proliferative diabetic retinopathy. Although new blood vessels may sound like a good thing,considering that the old blood vessels are damaged, the new blood vessels are actually more harmful than beneficial. The new blood vessels are extremely leaky and fragile, potentially leading to bleeding inside the eye (called vitreous hemorrhage) and usually resulting in severe vision loss. If not treated appropriately, this vision loss may be permanent.
Diabetic Eye Disease Symptoms
If the patient has fairly large, rapid shifts in their blood sugar levels, they may notice that their vision becomes blurry. This may occur prior to the diagnosis of diabetes mellitus, or it may develop after the initiation of treatment or a change in treatment of diabetes mellitus. This difficulty with vision or focusing will disappear once blood sugar levels have been stable for approximately one week.
Even if the patient has background diabetic retinopathy or early proliferative diabetic retinopathy, it is possible that they may not have any symptoms, or they may experience mild-to-severe blurring or vision loss. Many people with severe diabetic eye disease may not realize that they have a vision problem until it is too late and permanent damage has already occurred.
If the patient has a cataract, vision may become blurry or hazy. At night, the patient may experience glare from oncoming lights.
If the patient has glaucoma, they may not experience any symptoms until a significant loss of vision has already occurred.
When to Seek Medical Care
Even if the patient is not experiencing any symptoms due to diabetes mellitus, the patient should have an annual eye examination by an ophthalmologist (a medical doctor who specializes in eye disease and eye surgery).
If the ophthalmologist notices any significant signs of diabetic eye disease or if the patient requires treatment, exams may need to be scheduled more frequently than annually.
If the patient notes any significant changes in vision other than a mild temporary blurring, they should contact an ophthalmologist immediately.
Diabetic Eye Disease Treatment
Self-Care at Home
If the patient controls their weight, eats a proper diabetic diet, exercises regularly, monitors blood sugars, and takes the prescribed diabetic medications, the chances of developing serious problems due to diabetes mellitus decrease dramatically.
If the patient has diabetic eye disease and is experiencing serious visual problems, almost all treatment will require the care provided by an ophthalmologist.
Medical treatment of diabetic eye disease is generally directed at the underlying problem - the diabetes itself. The better control a patient has of the disease, the fewer problems they will have in the long run.
Monitoring the patient's glycosylated hemoglobin (hemoglobin A1C, Hb1AC) is the best assessment of the overall level of blood sugar control. A medical doctor will order this blood test at least once a year. If the patient's results are initially found to be abnormal or if the patient's self-test blood sugar results become more variable, then this blood test may be ordered more frequently.
For diabetic retinopathy, surgical treatment (for example, laser treatment) is the treatment of choice. Injections of corticosteroids or newer anti-vascular-proliferative medications in the area around the eye may be used.
Cataracts are commonly treated with cataract surgery.
Glaucoma requires the use of antiglaucoma medications.
Remember-Diabetes is a disease which can cause serious health problems. If you have diabetes:
Know your ABC
o A1C (Blood glucose levels or glycosylated Haemoglobin HB A1C)
o Blood pressure(BP)
o Cholesterol numbers
Take your medicine as prescribed by the doctor
Monitor your blood sugar daily
Reach and stay at a healthy weight
Get regular physical activity
Even if you have not been diagnosed with diabetes mellitus, eating healthy, maintaining a healthy weight, exercising regularly, and not smoking are advisable.