Lens (Cataract) Flashcards
definition of cataract
It’s lens opacity (OR loss of lens transparency)
Classification of cataract
- According to Cause
- According to Site
- According to Age
What is the meaning of:
Immature, mature and hyper mature cataract
Immature = slightly opaque
Mature = completely opaque
Hyper mature = dehydrated lens
The most common cause of cataract
Senile cataract
how can cataract cause glaucoma?
- Lens swelling (Phacomorphic Glaucoma)
- Lens protein leakage (Phacolytic Glaucoma)
- Surgical complications (Secondary Open-Angle Glaucoma)
a well-circumscribed complete or incomplete ring of pigment deposition on the anterior lens capsule surface, usually as a result of significant blunt eye trauma.this is called
Vossius ring
Types of eye injuries
أعرف أعرف انه سؤال غبي
- perforation
- blunt injury
- Glass – blowers caused by infrared energy.
- Electric shock .
- Ionizing irradiation.
types of cataract
according to cause
1- Congenital
2- Acquired
- Senile
- Traumatic
- Toxic
- Metabolic
- Complicated
types of cataract
According to Site
- Capsular: - anterior or posterior
- Subcapsular: - anterior or posterior
- Cortical: - anterior or posterior
- Nuclear
- Total
types of cataract
According to Age
- Soft cataract: - before 25y
- Hard cataract: - after 25y
what is the most common cause of complicated cataract
Anterior uveitis
mention 3 drugs that cause 3 forms of cataract
- corticosteroid = postiro subcapsular.
- chlorpromazine = deposition of fine yellowish brown granules under the anterior lens capsule.
- Miotics = ant. subcapsuler opacities.
the other name of
night blindness
Retinitis pigmentosa
can the Retinitis pigmentosa cause cataract and which type
yes,
posterior subcapsular
1. nuclear sclerosis
2. High myope
percent of rubella infection in pregnant women
15%
