Gradual Loss of Vision Flashcards
1
Q
Causes of gradual loss of vision
A
- cataract
- refractive error
- corneal blindness
- optic atrophy
- ARMD
- diabetic macular oedema
- chronic ocular inflammation/infection
2
Q
Definition of blindness
A
VA <3/60 in the better eye
3
Q
Who gets loss of central vision?
A
- ARMD
- Toxic optic neuropathy
4
Q
Who gets loss of peripheral vision?
A
- retinitis pigmentosa
- glaucoma
5
Q
2 types of cataract extraction
A
- ICCE (intracapsular)
- ECCE (extracapsular)
6
Q
How is traditional ECCE done?
A
- needle used to make a hole in the lens capsule
- cataract is expressed by putting pressure on the base of the cornea
7
Q
What is phacoemulsification?
A
- ultrasound probe is used to emulsify the cataract before sucking it out through a small wound
8
Q
Causes of leukocoria
A
- cataract
- toxoplasmosis
- toxocariasis
- retinoblastoma
- longstanding retinal detachment
- persistent posterior hyperplastic primary vitreous
9
Q
How does a pinhole work?
A
- only parallel rays of light pass through the hole so that the eye does not have to refract them to get a clear retinal image
10
Q
Hyperopia
A
Long sightedness
11
Q
Myopia
A
Short sightedness
12
Q
Characteristics of degenerative myopia
A
- develop laquer cracks in Bruch’s membrane and may lose vision through haemorrhage from neovasculatisation round the cracks and retinal degeneration
13
Q
What is keratoconus
A
Progressive myopic astigmatism
14
Q
Characteristics of trachoma
A
- entropion (lower eyelid folds in)
- trichiasis (ingrown eyelashes)
- scarring of conjunctiva and cornea
15
Q
Causes of interstitial keratitis
A
- congenital syphilis
- TB
- measles
