cataracts Flashcards
(13 cards)
cataracts
opacification of crystalline lens
symptoms of cataracts
- blurred vision, reduced VA
- changes in RE
- glare , increased scatter, night driving problems
- change in colour vision
- monocular diplopia
types of cataract
- age related
- trauma
- diabetic
- secondary cataract
- congenital
age-related
nuclear sclerosis
- loss of transparency and yellowing of lens nucleus
- myopic shift due to increase in refractive index of nucleus
age-related
posterior subcapsular
- focal dot like appearance
- located anterior
- glare
age-related
cortical
- vacuoles or clefts between lens fibres in cortex
- glare
Advanced age-related cataract
can be mixed eg cortical and nuclear sclerosis together
intumescent- swollen lens
mature- entire lens opaque
hyper-mature- capsule permeability increases and leaks lens matter, leading to shrinkage of cataract and wrinkiling of anterior capsule
morganian- total liquification of cortex, interior displacement of nucleus
trauma
- penetrating injury
- blunt trauma
- rare cause: infra red exposed ionizing radiation and electrical shock or lightning
diabetic cataract
- osmotic overhydration of the lens
- due to fly crust ions in blood sugar level
- leads to white punctuate it snowflake opacities
secondary cataracts
pharmaceutical induced
corticosteroids (anti-inflammatory drugs)
chloropromazine (anti-psychotic)
miotics
amiodarone to treat cardiac arrhythmias
secondary cataract due to other ocular disease
can develop as result of acute angle closure glaucoma or high myopia
- posterior subcapsular opacities
congenital and juvenile cataracts
congenital- detected at birth
juvenile- develop during childhood
types: lamellar, nuclear, sutural
treatment
- local anaesthesia
- removal of most the lens
- replacement by plastic implant
- phacoemulsification- liquification of lens using ultrasound probe
