Makindo Medical Notes

Related Subjects: Type 1 DM |Type 2 DM |Diabetes in Pregnancy |HbA1c |Diabetic Ketoacidosis (DKA) Adults |Hyperglycaemic Hyperosmolar State (HHS) |Diabetic Nephropathy |Diabetic Retinopathy |Diabetic Neuropathy |Diabetic Amyotrophy |Maturity Onset Diabetes of the Young (MODY)

Almost all individuals with type 1 diabetes, and most with type 2 diabetes, will have some degree of retinopathy after 20 years; for most, it will be mild and blindness can be prevented with timely intervention.

About

• 50% of Type 1 diabetics affected within 10-15 years.
• 50% of Type 2 diabetics affected within 15 years.
• Blindness from diabetic retinopathy is preventable with early diagnosis and treatment.

Diagrams

Aetiology

• Increased production of vascular endothelial growth factor (VEGF), triggered by hyperglycemia-induced capillary occlusion.
• Increased retinal capillary permeability, leading to retinal oedema.
• Stimulated angiogenesis and formation of new, fragile blood vessels.

Screening

• All diabetics should undergo regular fundoscopy with pupil dilation for early detection and prevention of damage.
• Diabetic retinopathy often remains symptomless until advanced stages requiring intervention.
• Most screening is conducted through digital imaging photography, with ophthalmology referrals as necessary.

Classification

• I. Background Retinopathy: No symptoms.
  • Microaneurysms (dots visible on angiography)
  • Micro haemorrhages (small blot haemorrhages)
  • Hard exudates (lipids, if near macula may require intravitreal treatment)
• II. Mild Non-Proliferative: Central visual loss.
  • Leakage and oedema in the macular area
  • Refer for ophthalmology assessment.
• III. Severe Non-Proliferative (Pre-Proliferative): No symptoms.
  • Venous abnormalities (e.g., beading)
  • Large blot haemorrhages
  • Cotton wool spots (ischaemic/infarcted areas)
• IV. Proliferative: Urgent referral required.
  • New vessels at disc or elsewhere
• Maculopathy: May cause reduced visual acuity; needs urgent referral.
  • Macular oedema treated with laser, intravitreal steroids, or anti-VEGF agents.
• Advanced Proliferative Disease: Requires urgent intervention.
  • Severe visual impairment due to vitreous haemorrhage, retinal detachment.
  • Pan-retinal photocoagulation can be very effective at preserving vision when performed early.

Management

• Laser therapy targets ischaemic areas to prevent further complications. Modern methods are more focused, preserving vision and avoiding night blindness (nyctalopia).
• Intravitreal anti-VEGF injections (e.g., ranibizumab, aflibercept) reduce the progression of proliferative retinopathy and help manage macular oedema.
• Macular oedema treatment may include intravitreal injections, which can restore vision in many cases.