Diabetic retinopathy
Diabetic retinopathy, which already threatens vision, usually appears 8-10 years after the onset of the disease. In order to minimize the risk, diabetic patients are recommended to strive for the following:
- Keeping blood sugar, blood pressure and cholesterol levels within normal, recommended values for diabetics.
- Ophthalmic screening is recommended annually for all patients who have had diabetes for 8-10 years. As a result, eye complications can be noticed and treated in time.
Effects of diabetes on the eyes
The retina is located at the back of the eye, its innermost layer. Its cells convert the light into an electrical signal and transmit it to the brain, which modifies this information into a visual image. This is an extremely energy-intensive process, which is why the choroid requires a constant blood supply, thanks to the tiny blood vessels there. High blood sugar damages these small blood vessels during the following three stages:
- Stage 1: Small bulgings (microaneurysms) appear on the walls of blood vessels, as a result of which minor bleeding may occur. Although it does not cause vision problems at this stage, the risk of later vision loss increases. This condition cannot be treated yet, but it can be prevented from progressing (see below). In medical terms, this stage is called latent (background) retinopathy.
- Stage 2: The number and size of the mentioned dissection increases, more and more vessels are affected, which manifests itself in an increasing amount and frequency of bleeding. If you develop this condition, you have a high chance of vision loss later on. In order to prevent this, you should have an eye fundus examination more often, every 3-6 months. This stage is the so-called preproliferative retinopathy.
- Stage 3: Vascular damage can lead to new blood vessel formation, major bleeding and scarring. The structure of these new blood vessels is abnormal, their walls are weak, so they are even more prone to bleeding. Scars, bleeding, and the formation of new blood vessels can lead to visual impairment and, in some cases, retinal detachment. At that point, the chance of vision loss is already high, so in order to preserve the remaining vision, medical interventions are required (see below). This stage is called proliferative retinopathy (the word proliferation means growth). The development of this condition can be stopped or slowed down by timely laser treatment (photocoagulation).
- Diabetic maculopathy: Edema (i.e. water) at the site of sharp vision, which can develop at any stage. In macular edema, the wall of the small blood vessels thins and serum leaks into the interstitial space. Since the macula is the site of sharp vision, long-standing glaucoma is associated with a decrease in visual acuity. Even if it exists, more frequent screening and treatment as needed is recommended.
The progress of the disease can be prevented - if it is detected at an early stage - with the help of lifestyle or other methods (change of medication, laser therapy).
Risk factors of diabetic retinopathy
Anyone with type 1 or type 2 diabetes has a chance of developing the disease. This risk increases further in the following cases:
- long-standing diabetes mellitus
- persistently high blood sugar levels
- hypertension
- high cholesterol level
- pregnancy
Symptoms of diabetic retinopathy
It is an insidious disease, as it usually has no symptoms in its early stages. That is why it is important to have an eye screening every year. Contact your GP or diabetologist as soon as possible if you notice the following:
- gradual deterioration of vision
- sudden vision loss
- eye pain, redness
- visual disturbances: floating figures in the field of vision, blurred or blurred vision
If the above symptoms appear, it is not certain that you have diabetic retinopathy, but it is important to investigate them as soon as possible. Don't wait until your next annual screening!
Eye screening for diabetes
It is recommended for all diabetics to have an eye examination every year. This is because:
- Diabetic retinopathy does not initially cause symptoms
- the condition can lead to blindness if not detected in time and not treated
- the test is able to screen for eye changes before they affect vision
- visual impairment can be prevented or even reduced if the damage is detected in time and with appropriate treatment
The screening is roughly a 20-30 minute examination, which is carried out after the administration of pupil-dilating eye drops, and consists of an examination of the fundus, determination of visual acuity and measurement of intraocular pressure. The effect of the pupil dilator does not go away immediately after the examination, it causes visual difficulties for approximately 2-6 hours, during which time you cannot drive a car!
Ways to reduce risk
The development and progression of diabetic retinopathy can be prevented by observing the following:
- maintaining blood sugar, blood pressure and cholesterol values at a normal level
- taking diabetes medications as prescribed by the doctor
- appearance at an eye examination every year
- in case of symptoms affecting vision, seek medical help as soon as possible
- maintaining a normal body weight and a healthy, balanced diet, regular exercise, and quitting smoking
Treatment of diabetic retinopathy
Treatment of retinopathy is only necessary if a significant difference is revealed during the ophthalmological examination, which may endanger your vision. In the case of earlier stages, you can prevent trouble by following the above advice.
The main treatment methods for advanced diabetic retinopathy are:
- Laser treatment: its goal is electrocoagulation (ie burning) of newly grown, abnormal small blood vessels in the retina, thereby stopping proliferative retinopathy. Laser treatment can also help in some cases of maculopathy.
- Medicinal injections into the eye: the goal is to treat severe maculopathy.
- Surgical removal of vitreous hemorrhage and scars from the eye (vitrectomy): only recommended if the retinopathy is so advanced that laser surgery alone is no longer suitable for treatment.
Laser therapy: In advanced diabetic retinopathy, new, small blood vessels grow in the layer of the retina. These blood vessels are not physiological, their walls are thin and permeable, which leads to hemorrhages in the fundus, which impairs vision. Laser treatment can burn and block these abnormal blood vessels by electrocoagulation. Thus, the source of bleeding is eliminated from the back layer of the eye, which prevents further deterioration of vision. Course of treatment:
- Before the procedure, the patient receives pupil dilating and anesthetic eye drops, and the doctor inserts a special contact lens, which helps to keep the eyelids open. Your task will only be to try to focus on a specific point.
- The operation usually takes 20-40 minutes and you can go home shortly afterwards, so you no longer have to spend the night in the hospital.
- The intervention is usually painless, but may cause a slight stinging sensation when the laser is treating certain areas of the eye.
Possible side effects that may appear a few hours after the procedure:
- blurred vision: you cannot drive a car after the operation, so you should ask a family member or friend to drive you home or choose public transport
- increased sensitivity to light: wearing sunglasses can solve the problem
- pain or discomfort in the eye: pain-relieving tablets can help
Like all interventions, laser eye surgery can have risks:
- reduced night/twilight or peripheral vision: as a result of which driving is no longer possible
- fundus hemorrhage
- creeping figures in the field of vision
- the appearance of the surgical area covered by the laser in the visual field: it takes a few months at most
- a small but persistent blind spot in the center of the visual field
If you notice any of the listed symptoms, contact your doctor immediately!
Intraocular (targeting the eyeball) injections: A procedure used in some cases of diabetic maculopathy, the essence of which is the introduction of a substance (anti-VEGF or steroids) that prevents further abnormal blood vessel growth. Through it, the current vision can be preserved, and in some cases it can be improved. Side effects of anti-VEGF injection: eye irritation, bleeding, itchy, dry or watery eyes, foreign body sensation in the eye. In rare cases, blood clot formation, which can lead to heart attack or cerebral infarction. A side effect of steroid injection can be an increase in intraocular pressure.
Eye surgery ( vitreoretinal surgery): The most severe cases of diabetic retinopathy can no longer be treated with the laser method alone. So if the size and number of scars are large, extensive bleeding has occurred in the retina, or a retinal detachment has occurred, we are forced to perform vitreoretinal surgery in order to prevent further vision loss. The operation is performed under local anesthesia or anesthesia, so it is not painful for the patient. It is necessary to wear a special bandage for a few days and blurred vision occurs, which can make everyday tasks difficult. Later risks of surgery: cataracts, further bleeding in the eye, retinal detachment, lacrimation, eye infection.
If you want to take part in an ophthalmology or diabetes specialist examination, make an appointment!
Read more about diabetes at the following links: