Hypertensive Retinopathy

Question 1

Pathophysiology

Answer 1

• Damage to small blood vessels in the retina cause the following:
  
  • Silver wiring or copper wiring - walls of the arterioles become thickened and sclerosed causing increased reflection of the light
  • Arteriovenous nipping - arterioles cause compression of the veins where they cross, due to sclerosis and hardening of the arterioles
  • Cotton wool spots caused by ischaemia and infarction leading to damage to the nerve fibres
  • Hard exudates caused by damaged vessels leaking lipids
  • Retinal haemorrhages caused by damaged vessels leaking blood
  • Papilloedema caused by ischaemia to the optic nerve resulting in swelling

Question 2

Keith-Wagener Classification

Answer 2

• Stage 1 - Mild narrowing of the arterioles
• Stage 2 - Focal constriction of blood vessels and AV nicking
• Stage 3 - Cotton-wool patches, exidates and haemorrhages
• Stage 4 - Papilloedema