•Dr Priscilia Imade
Every year, the month of November is dedicated to massive awareness on diabetes worldwide. We started the month discussing the effects of diabetes on the eyes including diabetic cataracts. We will delve further today with a look into diabetic retinopathy – the causes, risk factors, treatment and prevention.
Diabetic retinopathy is a condition where high blood sugar levels damage the blood vessels of the retina, which is the light-sensitive layer of tissue at the back of the eye that is responsible for sending visual information to the brain. These blood vessels may leak fluid or bleed, leading to swelling, scarring, or even detachment of the retina, which can severely impair vision. As the disease progresses, the retina may become unable to function properly, causing the individual to experience significant vision problems.
TYPES
There are two main types of diabetic retinopathy:
1. Non-proliferative diabetic retinopathy (NPDR): In this early stage, the blood vessels in the retina become weakened and small bulges or “microaneurysms” form. These can leak fluid into the retina, causing swelling and mild vision problems.
2. Proliferative diabetic retinopathy (PDR): This is the more advanced stage of diabetic retinopathy, where new, abnormal blood vessels begin to grow on the retina. These fragile vessels are prone to leaking blood, causing further damage to the retina and sometimes leading to retinal detachment and blindness.
CAUSES AND RISK FACTORS
The primary cause of diabetic retinopathy is prolonged high blood sugar levels, which can damage the walls of blood vessels, making them leak or rupture. The damage affects the retinal blood vessels’ ability to nourish the retina and maintain its health.
Other key factors contributing to the development and progression of diabetic retinopathy include:
1. Duration of Diabetes: The longer an individual has diabetes, the higher the risk of developing diabetic retinopathy. Those with poorly controlled blood sugar are particularly vulnerable.
2. Poor Blood Sugar Control: Chronic hyperglycemia (high blood sugar) can accelerate the damage to the blood vessels in the retina. Fluctuating blood sugar levels also contribute to the risk.
3. Hypertension (High Blood Pressure): High blood pressure can worsen the damage to retinal blood vessels, contributing to the progression of diabetic retinopathy.
4. High Cholesterol: Elevated cholesterol levels can exacerbate the damage to blood vessels, making them more prone to leakage and further complications.
5. Pregnancy: Pregnant women with diabetes are at increased risk of developing diabetic retinopathy due to hormonal changes that affect blood vessels. Diabetic retinopathy can also worsen during pregnancy.
6. Genetics: Some individuals may be genetically predisposed to develop diabetic retinopathy, although poor lifestyle choices can also worsen it.
SYMPTOMS
In the early stages of diabetic retinopathy, individuals may not notice any symptoms. As the disease progresses, however, the following symptoms can occur:
• Blurry or Distorted Vision: Blurry vision is one of the most common symptoms, particularly as swelling or bleeding occurs in the retina.
• Floaters: Dark spots or cobweb-like shapes may appear in the field of vision, caused by blood leaking into the vitreous gel inside the eye.
• Dark or Empty Areas in Vision: The loss of vision can occur when parts of the retina detach or when the new, abnormal blood vessels cause significant damage.
• Poor Night Vision: As diabetic retinopathy progresses, vision in low-light conditions may become more difficult.
• Sudden Vision Loss: In advanced stages, bleeding or retinal detachment can lead to sudden and severe vision loss.
DIAGNOSIS
The diagnosis of diabetic retinopathy typically involves a comprehensive eye examination conducted by an ophthalmologist or optometrist. The following diagnostic tests are commonly used:
1. Dilated Eye Examination: The optometrist will use eye drops to dilate the pupils, allowing them to examine the retina more thoroughly. This helps identify changes in the blood vessels, swelling, bleeding or the presence of new blood vessels.
2. Fundus Photography: A specialised camera is used to take detailed photographs of the retina, helping to document the condition and track any changes over time.
3. Fluorescein Angiography: A dye is injected into a vein in the arm and a special camera is used to take pictures of the retina. The dye highlights blood vessels and areas of leakage or bleeding.
4. Optical Coherence Tomography (OCT): This non-invasive imaging test provides cross-sectional images of the retina, allowing the Optometrist to assess swelling or fluid buildup in the retina.
Diabetic retinopathy is a serious eye disease that can lead to irreversible blindness. Early detection and management is the key to prevention and good eyesight.
For everyone who has been diagnosed with diabetes, make it a priority to have a dilated eye examination before the year ends.
*Dr Priscilia Imade is CEO, Modern Eye Clinic, Lagos. E-mail: moderneyecliniclagos@gmail.comAnother edition of the column returns on Monday in The Frontier.
