Cataract

• In cataract, the lens appear gray or milky
• Most common types of senile cataracts (Defined by their location in the lens)

  1. Nuclear cataract - caused by central opacity in the lens and has a substantial genetic component.
  2. Cortical cataract - Involves the anterior, posterior, or equatorial cortex of the lens.
  3. Posterior subcapsular cataracts - occur in front of the posterior capsule.
• Nuclear cataract - caused by central opacity in the lens and has a substantial genetic component
• Cortical cataract - Involves the anterior, posterior, or equatorial cortex of the lens
• Posterior subcapsular cataracts - occur in front of the posterior capsule.
• Pathophysiology of cataract:

  • Compaction and stiffening of the central lens material (nuclear sclerosis) as new layers of cortical fibers proliferate over time
  • Abnormal changes in lens proteins (crystallin) leading to loss of transparency
  • Pigmentation of lens proteins (yellow to brown)
  • Changes in the ionic components of the lens
• Causes of cataract:

  • Lifestyle factors like cigarette smoking, long-term corticosteroid use, sunlight exposure, diabetes, obesity, and eye injuries
  • Myopia (nearsightedness) associated with nuclear cataract
  • Density of cataract affecting vision
  • Cataract in the periphery not interfering with light passage
  • Degenerative changes in elderly patients
  • Genetic defects causing congenital cataracts
  • Traumatic cataracts from foreign body injury
  • Secondary effects in patients with uveitis, glaucoma, or systemic diseases
  • Drug or chemical toxicity
• Symptoms of cataract:

  • Blurred vision
  • Halos
  • Glare
  • Double vision
• Diagnostic procedures:

  • Snellen visual acuity test
  • Ophthalmoscopy
  • Slit-lamp biomicroscopic examination
• Treatment (Surgery) for cataract:

  • Phacoemulsification: ultrasonic probe breaks up the lens, foldable intraocular lens implant placed
  • Aphakic glasses for magnification
  • Contact lenses for almost normal vision
  • IOL implants: single focus, multifocal, accommodative
  • Extracapsular Cataract Extraction (ECCE): incision made in cornea, nucleus of lens removed, IOL implanted
• Self-care discharge instructions:

  • Protective eye patch for 24 hours post-surgery; sunglasses during the day, and metal guard shield at night for 1 to 4 weeks.
  • Expected side effects: morning discharge, redness, scratchy feeling.
  • Notify physician if new floaters, flashing lights, decrease in vision, pain, or increase in redness.
• Pre-operative medications:

  • Vigamox (Antibiotic)
  • Maxidex (Steroid)
  • Nevanec (Anti-inflammatory)
  • Drops to be administered morning of surgery and upon returning home, instill drops every 2 hours on the day of surgery
• OS - "oculus sinister" - "left eye"

  OD - "oculus dexter" - "right eye"
• Posterior subcapsular cataracts - occur in front of the posterior capsule
• Cortical cataract - Involves the anterior, posterior, or equatorial cortex of the lens
• Symptoms of cataract include blurred vision, glare from lights, halos around light sources, poor night vision, frequent prescription changes, double vision, fading or yellowing of colors, and reduced reading ability
• Age-related cataracts are usually bilateral but may be asymmetrical
• Age-related cataracts are usually bilateral but may be asymmetrical
• The most common type of cataract is nuclear cataract which occurs with ageing
• Subscapular cataract - Occurs in the area between the posterior capsule and the center of the lens
• Cortical cataracts - develop from the periphery towards the center of the lens
• The most common type of age-related cataract is nuclear sclerosis.
• The most common type of age-related cataract is nuclear sclerosis.
• aphakic glasses

  objects are magnified by 25%
• most common IOL is single focus lens of mono focal IOL