Diabetic retinopathy is one of the complications of diabetes mellitus, where high levels of sugar eventually result in damage to the retinal blood vessels, especially in light-sensitive tissues. This condition can be suffered by anyone who suffers from type 1 or 2 diabetes, especially those whose blood sugar is uncontrolled and have diabetes for long periods of time.
At first, diabetic retinopathy often shows only mild symptoms, or even no symptoms at all. However, if untreated, diabetic retinopathy can cause blindness. Therefore, people with diabetes melitus is always advised to perform routine eye examinations at least once a year despite not feeling any complaints on the eyes.
Causes of Diabetic Retinopathy
The retina is a layer in the back of the eye that is sensitive to light. The retina serves to convert the light entering the eye into an electrical signal that will be passed on to the brain. In the brain, this electrical signal will be converted into the shape of the image we see everyday.
Because of its important function, the retina requires a smooth blood supply of small blood vessels around the retina. In people with diabetes mellitus, blood sugar levels too much can clog these small blood vessels, so that the retina also lack of blood intake.
As a result, the retina will form new blood vessels to meet the needs of blood. Unfortunately, these newly formed blood vessels are not able to develop completely, so they are vulnerable to breaking or leaking.
Generally, diabetic retinopathy is divided into two types:
Non-proliferative diabetic retinopathy
This is the early stage of diabetic retinopathy. It is said non-proliferative because in this type, there is no growth (proliferation) of new blood vessels.
Non-proliferative diabetic retinopathy is characterized by a small protrusion (microaneurisma) arising from the blood vessels. This microaneurysm will eventually clog the veins, causing the veins to become bulging and uneven. As the blockage becomes more and more widespread, the neural and macular system (the core part of the retina) will also swell. The macular swelling, also called macular edema, is a condition that requires immediate treatment.
Diabetic retinopathy is proliferative
Proliferative diabetic retinopathy is a severe condition requiring immediate treatment. In this case, most of the retinal vessels have been damaged, resulting in the formation of new blood vessels that are not normal. This new blood vessel has a weak wall that will break easily, and blood will seep into the eyeball fluid or so-called viterus. As more and more, these fluid and blood stacks will increase the pressure of the eyeball and damage the innervation, thus causing a condition called glaucoma.
In addition, the growth of these new blood vessels will trigger the formation of scar tissue. This scar tissue will eventually pull the retina apart from the back of the eye. When this happens, a person may experience visual impairment.
Diabetic retinopathy is very likely to be experienced by diabetics who have long had the disease. The longer a person has diabetes the greater the risk of diabetic retinopathy, especially if the sugar content is not controlled. In addition, risks will also increase if supported by the following factors:
- It has high cholesterol and blood pressure levels
- The habit of smoking tobacco
- Hispanic, black, or Native American.
- Suffer from Down syndrome
Diabetic Retinopathy Symptoms
Initially, diabetic retinopathy may be asymptomatic. But as the condition progresses, symptoms can appear and usually affect both eyes. Some of the symptoms are:
- Visions decline slowly.
- The vision disappears unexpectedly.
- There were black objects or spots floating in the field of view.
- Shaded vision.
- Impaired color vision.
- Pain in the eyes or red eyes
These symptoms do not necessarily mean you have diabetic retinopathy, but it never hurts to see a doctor immediately. Do also routine eye examination even though you feel there is nothing wrong with the eye condition for the disease can be detected and treated early.
Diagnosis of Diabetic Retinopathy
To establish a diagnosis of diabetic retinopathy, the physician needs to see the condition inside your eyeball with an examination called funduscopy. The condition within a person’s eyeball will be most clearly seen in the pupil’s condition is wide open. Therefore, the doctor may provide eye drops that aims to dilate your pupils. The eye drops can make your short-term vision blur, but this will only gradually disappear when the drug’s effects are gone.
At the time of fundoscopy, the doctor will look for some of the following:
- Abnormal blood vessels
- Swelling and blood and fat deposits in the retina
- The growth of new blood vessels and scar tissue
- Bleeding in the eyeball fluid (vitreus)
- Regardless of the retinal lining
- Abnormalities in the eye nerve
To see whether there are abnormalities in the blood vessels of the eye, especially newly formed blood vessels, doctors will usually perform an examination called fluorescence angiography. In this examination, you will be given drops to dilate the pupil, then the doctor will inject a special dye in your arm. This dye fluid will eventually fill the blood vessels in your eyeballs, and your doctor will take a picture of the state of the blood vessels inside the eyeball using a special tool. From there it will be clear whether there is a narrowing or rupture of blood vessels, and the presence or absence of leakage of fluids.
Another possible procedure is to perform an optical coherence tomography (OCT) examination that will give an image of the retinal eye thickness. From this examination, it will be seen clearly if there is leakage of fluid into the retinal tissue. OCT examination can also be used to determine the success of therapy.
Treatment of Diabetic Retinopathy
The choice of diabetic retinopathy treatment depends on the type and degree of disease severity, namely:
- Non-proliferative diabetic retinopathy. At this stage, the patient may not require treatment but will be monitored first by the doctor. Patients will be advised for routine control to an ophthalmologist and diabetes expert (endocrinologist), as well as learn to control blood sugar levels because this step can usually slow the progression of the disease.
- Diabetic retinopathy is proliferative. At this stage there are several surgical procedures that may be recommended to patients, among others:
Anti-VEGF injection into the eye – This injection is given directly into the eye and is useful to prevent the formation of new blood vessels in the back of the eye. The injections are administered once a month, and are gradually reduced or stopped when the condition has stabilized. Some side effects that may arise, is the irritation of the eye, feel something in the eye, watery eyes or itching, bleeding, until blood clotting.
Vitrectomy – This operation aims to remove blood and scar tissue from the center of the eye by making small incisions in the eye with the help of general anesthesia and local anesthesia.
Treatment with focal laser or photocoagulation – This laser treatment aims to slow or stop the points of leakage of fluid or blood within the eye.
Treatment with scattered laser beam or panorcan photocoagulation – Slightly different from the focused laser beam, in this treatment the focus of the rays is given more widely so that it can hit a specific area in the retina directly. This laser light therapy will burn the new blood vessels that are not normal so that shrink and eventually become scar tissue.
In addition to painkillers, doctors will advise patients not to operate vehicles or heavy machinery and use sunglasses.
Diabetic Retinopathy Complications
If not treated promptly, new blood vessels that grow abnormally in the retina can cause serious visual impairment to blindness. Some of the complications of diabetic retinopathy that may occur, among others:
- Bleeding vitreous – Newly formed blood vessels will be susceptible to rupture, so the blood will enter the center of the eye. If blood leaks only a little, you might just see a dark shadow floating around in your field of vision. The more blood that leaks the more blocked the vision. Although the blood may gradually disappear within weeks or months, the patient may still risk permanent loss of vision if the retina has been damaged.
- Detached Retina – New blood vessels arising from diabetic retinopathy will stimulate the formation of a scar tissue in the retinal lining. It is this scarring that is at risk to pull the retina off its base, so that it can produce symptoms such as blurred vision, a curtain in the field of vision, flashes of light, or even blindness.
- Glaucoma – When the blood vessels grow in the front of the eye, the tear duct can become blocked, so the fluid will accumulate in the eyeball and the pressure of the eyeball will increase. This increased pressure in the eyeball is called glaucoma. Glaucoma can damage the visual nerves, which may cause vision problems.
Blindness – Eventually diabetic retinopathy, glaucoma, or both can cause blindness.
Prevention of Diabetic Retinopathy
Setting blood sugar levels well is one way of avoiding loss of vision. Here are the other steps you can take:
- Do aerobic activities, such as walking for at least two and a half hours each week.
- Start a healthy and balanced eating plan that suits your condition. Also reduce the intake of sugar, salt, and fat.
- Reduce weight, for owners of obesity conditions.
- Stop consuming alcoholic beverages.
- Stop smoking or smoke tobacco.
- Drink diabetes or insulin medicine as recommended by physician
- Monitor your cholesterol levels.
- Monitor your blood sugar levels through a blood sugar test in accordance with the doctor’s instructions.
- Discuss with your doctor about the A1C hemoglobin test that you may be able to do in addition to a blood sugar test.
- Always be vigilant if you feel a change in your eyesight.
- Regular eye exams and blood pressure are also early preventative measures to prevent the disease from progressing to worse.
- Doc. RS Kasih Ibu