chapter 15- vision Flashcards
(140 cards)
1
Q
what is apart of the visual system
A
eyes
accessory structures
optic nerve
tract
pathways
2
Q
3 roles for the visual sytem
A
sight
eye movement
provide info for pastural and limb control
3
Q
stimulus may be billions of miles away and still be detected
A
visual stimuli
4
Q
info regarding light vs dark, movement and color
A
visual input
5
Q
pathway for how eyes respond to light
A
initiate afferent AP-> optic nerves-> optic chiasma-> optic tracts to brain
6
Q
how many pathways does the visual association area have and what are they
A
2
ventral & dorsal path
7
Q
ventral path is where in the brain
A
temporal visual cortex
8
Q
dorsal path is where in the brain
A
parietal virtual cortex
9
Q
ventral path asks what question
A
what
10
Q
dorsal path asks what questions
A
where
11
Q
what does the frontal eye field do
A
interpret location of objects
12
Q
7 bones surround eyeball and adipose tissues as well (posterior)
A
eye orbit bones
13
Q
hair superior to eye orbit. prevent perspiration from running into eyes and irritating, it also shades from direct sunlight
A
eyebrows
14
Q
palpebrae; works with eyelashes to protect from foreign objects, lubricates eye, regulates light entering eye, rapid blinking (25x/minute)
A
eyelids
15
Q
what muscle opens eye
A
levator palpebrae
16
Q
what muscle closes eyelid
A
orbicularis oculi
17
Q
space between 2 open eyelids
A
palpebrae fissue
18
Q
angle- join medial/lateral margin= blank= modified sebaceous/ sweat glands
A
canthus
19
Q
5 layers
A
skin, areolar CT, skeletal muscles, tarsal plate (dense CT), and papebral conjunctiva
20
Q
what forms shape of eyelid
A
tarsal plate
21
Q
what lines inner eyelid
A
palpebral conjunctiva
22
Q
2-3 layers of hair at free edge of eyelid
brush away dust/ foreign objects from eye
A
eyelashes
23
Q
sweat glands that lubricates eyelash follicles
A
ciliary glands
24
Q
gland inflammation at base of eyelash, usually bacterial infection, pain
A
stye
25
tarsal=sebaceous glands at inner margins of eyelids
sebum lubricates tears and restrains tears from flowing over eyelid margi. airtight
meibomian glands
26
meibomian cyst is
chalazion
27
chalazion=meibomian=
infection/ blockage of oil gland
28
is there pain in chalazion
lack pain
29
treatment for chalazion
warm compresses for 10-15 min/ 3-4 time a day
massage
antibiotics
I&D
steroid injection
opthalmologist
30
thin, transparent mucous membrane on eyelid, surface of eye, lubricate eye
conjunctiva
31
cover inner eyelid
palpebral conjunctiva
32
covers anterior white surface of the eye
bulbar conjuctiva
33
inflammation of conjuctiva
conjuctivitis
34
inflammation of conjuctiva=
pinkeye
35
is pinkeye contagious
yes
36
causes for conjunctivitis
bacterial
viral
allergic
foreign body or chemical splash
37
S&S for conjunctivitis
redness, itchy, gritty, discharge with crust, tearing, photophobia
38
treatment for conjunctivitis
contacts out
compresses
antiinflammatory drops
decongestants
steroids
antivirals
antibiotic eye frops
pataday
artifiical tears
39
what is innervated by parasympathetic fibers of facial CN VII
lacrimal gland
40
role in eye protection
lacrimal apparatus
41
producing tears ->
lacrimal ducts and across anterior eye surface
42
lacrimal gland goes into
lacrimal sac and through nasolacrimal duct into nasal cavity
43
what moisturize eye surface, lubricate eyelids, wash away foreign body
lacrimal gland
44
what is tear composition
predominately H2O, salt, mucus, lysozyme, immunoglobulins
45
6 extrinsic eye muscles
superior, inferior, medial, lateral rectus
superior, inferior oblique
46
4 extrinsic eye muscles are controlled by? and what are they
oculomotor CNIII, SR,IR, MR, IO
47
1 extrinsic eye muscle are controlled by
abducens and trochlear
48
abducens controls what muscle
LR
49
trochlear controls what muscle
SO
50
hollow sphere filled with vitreous humor
eyeball
51
3 tunics comprise wall:
fibrous tunic
vascular tunic
nervous tunic
52
outer. sclera and cornea
fibrous
53
middle. choroid, cillary body and iris
vascular
54
inner. retina
nervous
55
white of the eye, posterior 5/6. firm, opaque tissue= dense CT with elasticity
maintains shape of eye, protects internal area, attachment for muscles
sclera
56
anterior, avascular, transparent structure, stratified squamous epithelium
inner surface is simple squamous. allows light into the eye. focuses
cornea
57
large collagen fibers= white, smaller with low H2O content= transparent
fibrous
58
transplant for fibrous
EZ to access/remove. avascular, decreased immune activity
59
middle tunic layer
vascular
60
what does the vascular tunic contain
BV and melanin pigmanet cells
61
order of arteries in vascular tunic
internal carotid artery
ophthalmic artery
short cililary arteries
62
thin membrane
choroid
63
ring and processes, attached to lens by suspensory ligaments
choroid body
64
produce aqeous humor
ciliary processes
65
what contains smooth muscles and act as a sphincter
choroid body
66
contract to change shape of lens=
focus
67
colored portion of eye
iris
68
contracts pupil to regulate amount of light entering eye
iris
69
outer muscle fibers-radial= dilate
dilator pupillae
70
central muscle fibers-circular=constrict
sphincter papillae
71
inner posterior eye. retina is what tunic layer
nervous
72
3 neuronal layers are
ganglion, bipolar, photoreceptor cells
73
pigmented simple cuboidal epithelium
outer pigmented layer
74
responds to light
contains photoreceptors: 120 million RODS-low liht
6-7 million cones- bright light
inner neural layer
75
rods is bright or low light
low light
76
cones is bright or low light
bright light
77
what do you use to examine retina
use ophthalmoscope
78
small yellow spot, fovea centralis (center)- most focus (cones)
greatest visual acuity (direct vision)
macula lutea
79
white spot, central retinal artery in and central retinal vein out of the eye
where optic nerve exists eye
no photoreceptors=blind spot
optic disc
80
no photoreceptors=
blind spot
81
nicking of retinal veins where abnormal pressure arteries cross over
hypertension
82
assiciated with hydrocephalus
increased CSF pressure
83
increased csf pressure may cause
optic disc to swell causing papilledema
84
opque lens. not see well at night, halos around lights
cataracts
85
how do you treat cataracts
surgically remove lens and replace with artificial lens
86
cotton wool spots-opque fluffy white patches, due to ischemia in retinal nerve
diabetic retinopathy
87
what are the eye chambers
anterior, posterior, virteous
88
where is the anterior chamber of the eye
between cornea and iris
89
what is the anterior chamber filled with
aqueous humor
90
what does the aqueous humor maintain
intraocular pressure and eyeball shape
91
condition where there is increased IOP
glaucoma
92
what provides nutrition to avascular cornea
anterior chamber
93
what is aqueous humor made by
ciliary processes, returned to circulation via scleral venous sinus
94
where is the posterior chamber
between iris and lens
95
what is the virteous chamber filled with
viteous humor
96
what chamer maintains IOP, shape of eye, holds len and retina in place and has slow turnover
vitreous chamber
97
what chamber helped with refraction of light
vitreous
98
pathway in which the eye function
light converge-> cornea to aqueous humor thru pupil-> lens thru vitreous humor-> retina
99
what does the retina contain
photoreceptors (rods and cones)
100
what is an eye function
it converts light energy into AP and APs sent to brain along the optic nerve
101
what is an accommodation
changes the shape of lens to focus on object close or distant
102
focus in front of retina; see close, distance blurred
eye becomes too elongated; nearsighted; correct with concave lens to diverge light
myopia
103
4-8 radiating cuts in cornea, cornea flattens, eliminates myopia
issues with visual acuity, glare
radial keratotomy
104
laser procedure where thin part of cornea cut away to make cornea less convex. better results
LASIK
105
focus behind the retina; see distance, close is blurred
eye becomes too short, lazy; farsighted; correct with convex lens to converge light
hyperopia
106
old vision; unavoidable degeneration of accomodation of eye
presbyopia
107
when does presbyopia start
mid 40s
108
what causes presbyopia
if you read a lot
109
how do you prevent presbyopia
use bifocals or prorgressive lenses if need to compensate for close or distant vision
110
irregular bulge or cornea or lens
astigmatism
111
light not focused on a singple point but instead is
blurred
112
how do you correct astigmatism
glasses with opposite curve gradient
113
if the astigmatism is irregular is it easy or hard to correct
hard
114
color blindess is
color vision deficiency
115
color blindness is a dysfunction of
1 or more of 3 photopigments in color vision
116
if 1 pigment is dysfunctinal and the other two are ok what is it called
dichromatism
117
dichromatism=
red-green color blindness
118
ratio of males affected by color blindness
1 in 12 males
119
ratio of females affected by color blindness
1 in 200
120
color blindess is x linked recessive that affects
males
121
are females carriers for color blindness
yes
122
what chromosome is mutated in blue-yellow color blindess
chromosome 7
123
monochromatism =
no color
124
as we age what happens to color blindness
ability to distinquish colors degrades naturally as we proceed to old age
125
color blindness is also due to
illness, physical or chemical damage to the eye, optic nerve, brain parts or med toxicity
126
adaptation for light to dark
5 minutes to start, accomodate within 30 minutes
127
adaptation for dark to light
(see white), 1 minute to start; accomodate in 5-10 minutes
128
3D and depth perception is what
stereoscopic vision
129
overlapped area in stereoscopic vision means
seen by both eyes at same time
130
what does binocular vision give us
depth perception as 2 eyes from diffenet angles
131
ability to see in low light conditions, impaired rod function; prolonged vitamin A deficiency causing degeneration. not function in dim light
night vision
132
rabbits and pigeons have what kind of eyes and results in what
lateral w little overlap so less depth perception
133
whats an emergency situation in the ey
retinal detachment
134
what is retinal detachment
layers separate and virteous humor flows between them and that results in permanent blindness
135
is there nutrition from bvs in retinal detachment
no
136
causes of retinal detachment
traume, head jerk in opposite direction,
MVA: painless process
137
risk factors for retinal detachment
> age 50, hx retinal detachment, FH of retinal detachment, xs myopia, prior eye surgert, eye disease
138
dx for retinal detachment
retinal exam, ultrasound
139
S&S for retinal detachment
sudden flashes of light, floaters, see spots, sensitive to light, blurred vision, unable to see dim light, temporary loss of vision in 1 eye, tunnel vision or visual loss
140
treatment for retinal detachment
laser surgery, cryosurgery
