Question

Describe important features of diabetic retinopathy.

Hint:

In proliferative diabetic retinopathy, the presence of new blood vessels (neovascularization) is the hallmark, and early intervention is critical to prevent vision loss.

Answer 1

Step 1: Features of Each Stage of Diabetic Retinopathy.
(1) Mild Non-Proliferative Diabetic Retinopathy (NPDR):
- Microaneurysms: Small outpouchings of the retinal capillaries are the hallmark of this stage. - No significant visual impairment: Most patients are asymptomatic at this stage, and the disease is usually detected during routine eye exams.
(2) Moderate Non-Proliferative Diabetic Retinopathy (NPDR):
- Retinal Hemorrhages: Small dot and blot hemorrhages are commonly seen in this stage. - Hard Exudates: Lipid deposits in the retina due to leakage from abnormal blood vessels. - Cotton Wool Spots: Small white patches caused by retinal ischemia, indicating retinal nerve fiber layer infarcts.
- Vision may remain unaffected, but the disease is more likely to progress to severe NPDR or proliferative retinopathy.
(3) Severe Non-Proliferative Diabetic Retinopathy (NPDR):
- Venous Beading: Abnormal dilatation and constriction of the retinal veins. - Intraretinal Microvascular Abnormalities (IRMAs): Early signs of neovascularization in the retina. - Massive Retinal Hemorrhages: Extensive areas of hemorrhage in the retina. - Risk of Progression to PDR: This stage has a high risk of developing proliferative diabetic retinopathy (PDR) within a year.
(4) Proliferative Diabetic Retinopathy (PDR):
- Neovascularization: Growth of new, abnormal blood vessels at the optic disc and elsewhere in the retina. - Vitreous Hemorrhage: Bleeding from the new vessels into the vitreous body, causing a sudden loss of vision. - Fibrous Tissue Formation: Scar tissue can contract and cause retinal detachment, further compromising vision. - Severe Vision Loss: If untreated, PDR can lead to permanent blindness.