Epidemiology

Etiology

Acquired cataracts (> 99%)

• Age-related cataract (> 90%)
• As a result of ocular diseases (complicated cataract)
  • Diabetes mellitus
• Drug-induced
  • Glucocorticoids (local and systemic)
    • Glucocorticoids increase oxidative stress within the lens by reducing antioxidant defenses like glutathione
• Chronic alcohol and tobacco use
• Traumatic (traumatic cataract)
• Eye infections
• Excessive sunlight or UVB exposure

Pathophysiology

• Oxidative damage & opacification of the lens
• Cataracts caused by diabetes: see Diabetes mellitus#Other complications

Clinical features

• Painless, progressive, bilateral vision loss
• Difficulty with nighttime driving
• Loss of red reflex
• Opacified lens

Diagnostics

• Fundoscopy
  • Changes to the red reflex (the reflection of light in the ocular fundus, which is normally red in color), including:
    • Opacities (including leukocoria)
    • Darkening
    • Absent or decreased red reflex
• Slit-lamp examination
  • Common: grey, white, yellow, or brownish clouding of the lens (see also “Types of cataracts”)

Treatment