opthamology Flashcards
1
Q
vision loss
what can go wrong?
A
- focused light doesnt reach the retina
- the retina doesnt turn it into nerve impulses
- the optic nerve doesnt tranmit the impulses to the brain
- Brain doesnt precess them correctly
2
Q
Cornea function
A
- transmission of light into the eye
- refraction of light
3
Q
optics of eye
A
emmetropia
- normal eye
hyperopia
- flat cornea, light not focused til behind eye
- farsighted
Myopia
- steep cornea
- near sighted
4
Q
cornea
major abnormalities
A
- epitheliopathies (disruption, edema)
- stromal opacities
- scarring
- edema (endothelial cell dysfunction) - irregular shape
5
Q
cornea
clinical disorders
A
- keratitis sicca
- infectious keratitis
- peripheral ulcerative keratitis (RA)
- Pseudophakic corneal edema
- keratoconus
6
Q
cornea
symotoms
A
- everything is white(opacities)
- colored haloes (edema)
- distortion (irregularities)
- ghost images (refractive errors, epitheliopathies)
7
Q
ocular surface
definition:
important functions:
A
def:
- outer surface of globe
- inner surface of eyelid
imp functions:
- protects eye from exogenous factors
- maintains moist surface
8
Q
ocular surface
clinical disorders:
A
- primary corneal disease
- dry eyes
- aqeous tear dificiency
- tear dysfunction - conjunctival disease
9
Q
Eyelids
function:
major abnormalities:
A
function:
- protect ocular surface
- meaintain normal tear film
major abnormalities:
- structural defects (tumors)
- entrpion (trichiasis)
- Ectropion/ eyelid laxity
- dysfunction (lagophthalmos, ptosis)
- weakness
10
Q
anterior segment
diseases:
A
- diseases reduce vision by affecting function of other tissues
- glaucoma
- inflammation (uveitis) - most anatomic changes dont affect vision directly
except:
- opacified media (blood, fibrin)
- membranes
- cataracts
11
Q
lens
functions:
major abnormalitie
A
function:
- transmission of light
- additional focus of light
- accomodation- (change focus for near vision)
major abnormalities:
- dislocation
- opacification (cataract)
- swelling (change in refractive state)
- hardening (failure to change shape; lack of accomodation)
12
Q
lens
symptoms:
A
- poor quality of vision (poor color vision, altered contrast sensitivity)
- poor focus
- glare, ghost images
- “foggy vision”, “haze”
13
Q
Retina
major abnormalities:
A
- loss of tissue (infection, degeneration)
- edema
- disturbances of normal position
- traction
- retinal detachment
14
Q
retina
symptoms:
A
- scotomata (blind spots), curtains
- poor quality
- blurring
- patchy loss
- metamophopsia (distortion)
15
Q
international ocular infections
A
- trachoma
- onchocerciasis
- leprosy