Diabetes mellitus is a metabolic disease characterized by elevated blood glucose levels and impaired glucose metabolism.
According to the International Diabetes Federation, 1 in 10 adults worldwide is affected by diabetes.
Patients with diabetes have an increased risk of developing ocular conditions such as cataract and glaucoma. However, the most serious threat to vision is damage to the retina, a condition known as diabetic retinopathy.
Stages of Diabetic Retinopathy
1. Non-Proliferative (Background) Diabetic Retinopathy
This is the earliest stage of the disease and is characterized by:
•microaneurysms
•retinal hemorrhages
•hard exudates
Leakage from damaged blood vessels often leads to retinal swelling (edema), resulting in reduced vision.
2. Proliferative Diabetic Retinopathy
At this stage, poor blood circulation within the retina leads to the development of ischemic areas with reduced oxygen supply.
In an attempt to compensate, the eye forms new abnormal blood vessels (neovascularization). These vessels are fragile and prone to bleeding.
3. Advanced Stage of Proliferative Diabetic Retinopathy
The advanced stage includes:
•vitreous hemorrhage
•tractional retinal detachment
•neovascular glaucoma
•severe vision loss
Symptoms
The impact of diabetic retinopathy on vision varies depending on the stage of the disease. Common symptoms include:
•blurred vision
•floaters and flashes of light
•sudden decrease or loss of vision
Diagnosis
Diabetic retinopathy is diagnosed through:
•fundoscopic examination
•Optical Coherence Tomography (OCT)-Angio OCT
OCT is a painless, non-invasive imaging technique that provides high-resolution cross-sectional images of ocular structures. It does not use radiation, but rather a beam of light.
Macula of a healthy eye as visualized by OCT
Treatment
Treatment of diabetic retinopathy depends on the stage of the disease and the underlying pathology. Patients undergo a series of examinations to monitor disease progression, including:
•fluorescein angiography
•retinal photography
•Optical Coherence Tomography (OCT)-Angio OCT
•B-scan ultrasonography of the fundus (when required)
Treatment options include:
Laser therapy
When applied at the appropriate time, laser treatment can prevent vision loss by eliminating abnormal blood vessels and reducing the risk of hemorrhage. It is important to note that laser therapy aims to preserve existing vision rather than improve it.
Intravitreal injections (anti-VEGF agents)
These are primarily used in cases of diabetic macular edema. Treatment is typically administered monthly for the first three months and then adjusted based on disease progression, as monitored by OCT.
Vitrectomy
Surgical removal of the vitreous body is performed in cases of vitreous hemorrhage or impending retinal detachment.
Prevention & Follow-Up
Proper blood glucose control is essential, as poor glycemic regulation accelerates the progression of diabetic retinopathy.
Regular monitoring of blood sugar levels and routine ophthalmologic examinations allow for early detection and timely treatment of retinal changes, helping to preserve vision.
Markakis Apostolos MD
Ophthalmologist Surgeon
