Opthamology Flashcards
1
Q
what is the anterior segment of the eye
A
from cornea to the back of the lens
2
Q
what is the posterior segment of the eye
A
lens to back of eye where optic nerve ecxits
3
Q
what is the anterior chamber of the eye
A
between the cornea and the iris/pupil in the anterior segment
4
Q
what is the posterior chamber of the eye
A
between the iris/pupil and the lens in the anterior segment
5
Q
describe the flow of the aqueous humor
A
produced by the ciliary body epithelium with beta receptors on it –> posterior chamber –> pupil –> anterior chamber –> Trabecular meshwork –> canal of schlemm by the corena/scleral junction.
6
Q
what are refractive errors
A
common cause of impaired vision
correct with glasses
refractory power of the lens/cornea does not make image onto the retina
7
Q
what is hyperopia
A
far sightedness (can see far aways)
refractive power pf lens/cornea is not strong enough
image is behind the retina/ eye is too short
correct with biconcave lens?
8
Q
what is myopia
A
near sightedness (can see close ups)
refractive power is too strong
image is infront of the retnia/eye is too long
correct with biconvex lens
9
Q
what si astigmatism
A
abnormal curvature of the cornea - different refractive power at different axes
10
Q
what is presbyopia
A
age related impaired accommodation - trouble focusing on near objects - possible due to decreased lens elasticit
reading glasses
11
Q
what causes presbyopia
A
decreased lens elasticity (farsightedness - image past retina, cannot see close)
12
Q
causes of cataracts
A
most commly - advanced age
diabetes mellitus - osmotic damage
congenital rubella, CMV
corticosteroids
13
Q
painless
often bilateral
opacification of lens
A
cataracts
14
Q
what are RF for cataracts
A
increased age, excessive sunlight prolonged corticosteroid use classic galactosemia galactokinase deficiency diabetes mellitus/sorbitol trauma infection
15
Q
what is glaucoma
A
optic disc atrophy with characteristic cupping/thinning of outer rim of optic nerve head
16
Q
how does glaucoma present
A
usually with increased IOP and progressive peripheral visual field loss
17
Q
cupping of optive nerve
A
glaucoma = thinning of outer rim of optic nerve head
18
Q
what is open angle glaucoma
A
primary cause is unclear
secondary - blocked trabecular meshwork due to wbcs @ uveitis, rbc @ vitreous hemorrhage or retinal elements @ retinal detachement
19
Q
risk factors for open angle glaucoma
A
increased age
African American race
family history
20
Q
cxpx of open angle glaucoma
A
painless
most common type in the USA
cupping of optic nerve (Atrophy/thinning of edges)
(usually increased IOP)
21
Q
what is the cause of primary closed/narrow angle galucoma
A
enlargement or forward movement of the lens against the central iris/pupil margin –> obstrucst normal aqueous flow through pupil – fluid builds up behind the iris – pushes peripheral iris against cornea – impede flow through trabecular meshwork
22
Q
what is the cause of secondary close/narrow angle glaucoma
A
hypoxia from retinal disease (DM ro vein occluisn( that induces vasoproliferation in the iris that contracts angle
23
Q
what can cause vasoproliferation in the iris - contraction of angle - gluacoma
A
diabetes or vein occlusion - hypoxial retina disease
24
Q
what type of glaucaom is associated with diabetes
A
secondary close/narrow angle glaucoma due to vasoproliferation from induced h;ypoxic state int eh iris that closes the angle - fluid buildup and increased IOP
25
cxpx of chronic closed/narrow angle glaucoma
often asymptomatic with damage to the optic nerve and peripheral vision
26
describe acute closed/narrow angle glaucoma
OPTHALMIC EMERGENCY
increased IOP pushes iris forward - angle closes abruptly
```
very painful
red eye
sudden vision loss
halos around lights
rock hard eye
frontal headaches
```
27
what is contraindicated in acute closed/narrow angle glaucoma
mydriatics - epinephrine
28
```
very painful
red eye
sudden vision loss
halos around lights
rock hard eye
frontal headaches
```
primary acute close/narrow angle glaucoma
acute is probly usually primary (Secondary due to hypoxia at venous occlusion or dm so those are probly chronic and asxtic with peripheral vision loss and optic nerve damage)
29
optic nerve damage
peripheral vision loss
asxymptomat
chornic (probably secondary to dm or vein occlusion) closed/narrow angle glaucoma
30
what is uveitis
inflammation of the uvea (iris, ciliary body and choroid)
31
what are the layers of the eye ball
outside - sclera
middle - choroid --> iris
inner - retina
32
what is anterior uveitis aka
iritis
33
what is posterior uveitis aka
choiroiditis
34
clinical presentation of uveitits
hypopyon - pus in the anterior chamber (between cornea and iris of the anterior segment)
conjunctival redness
35
hypopyon
| conjunctival redness
uveitis
36
eye complication of sarcoidosis, ulcerative colitis and ankylosing spondylitis, juvenile idiopathic arthritis, HLA-B27s, rheumatoid arthritis
uveitis
hypopyon
conjunctival rednesss
37
what is uveitis a complication of
```
systemic inflammatory diseases:
rheumatoid arthritis
HLA B27s - ankylosing spondylitis
juvenile idiopathic arthritis
ulcerative colitis
sarcoidosis
```
38
describe age related maculodegeneration
degeneration of the macula/cenral area of the retina
39
describe dry age related macular degeneration
non exudative, accoutns for > 80 % of all cases
deposition of yellowish extracellular material (DRUSEN) beneath the BRUCH membrane (between retina and choroid) and the retinal pigment epithelium
presents with a gradual decrease in vision
40
elderly individual
| gradual decrease in vision
age related macular degeneration
| DRY
41
how do you prevent progression of dry age related macular degeneration?
multivitamins and antioxidant suppliments
42
describe wet age related macular degeneration
exudative, 10-15% of all cases
bleeding secondary to choirodal neovascularization
rapid vision loss
43
elderly individual
| rapid vision loss
wet age related macular degeneration (choroidal neovascularization bleeding; exudative)
44
how to treat wet age related macular degeneration
anti VEGF: ranibizumab/bevacizumab
| or laser
45
what causes damage in diabetic retinopathy
hyperglycemia
46
describe nonproliferative diabeti retinopathy
damaged capillaries leak blood - lipid and fluid seep into retina - hemorrhage and macular oedema
47
how to treat nonproliferative diabetic retinopathy
blood sugar control
| macular laser
48
describe proliferative diabetic retinopathy
chronic hypoxia results in new blood vessel formation with resultant traction on the retina
49
what can proliferative diabetic retinopathy cause
hemorrhage - wet age related macular degeneration OR chronic acute angle glaucoma (chronic hypoxia - retinal damage)
50
how to treat proliferative diabetic retinopathy
periperahl retinal photocoagulation
| anti VEGF - bevacizumab/ranibizumatab (same as wet age related macular degeneration)
51
desecribe retinal vein occlusion
blockade of central or branch retinal vein due to compression from nearby arterial atherosclerosis
52
what does retinal look like in retinal vein occlusion
retinal hemorrhage
venous engorgement
edema
BLOOD and THUDNER
53
blood and thunder
retinal vein occlusion
54
cxpx of rential vein occlusion
sudden, painless,s unilateral vision loss
swelling of optic disk
engorgement of retinal veisn with hemorrhage
55
what can casue retinal vein occlusion
hypercoagubale states ie polycythemia
| compression by nearby arterial atherosclerosis
56
describe retinal detachment
separation fo neurosensory late of retina the one with the rods and cones from the outermost pigmented epitlieum (normal roel is to shield excess light and support retina) -- degeneration of photoreceptprs - vision loss
57
what can cause retinal detachment
```
diabetic traction (proliferative)
retinal breaks
inflammatory effusions
```
58
how does retinal detachment look on fundoscopy/
splaying and paucity of retinal vessels
59
how else can you visualize retinal detachment
cross sectional optical ultrasound
60
who is more common to get retinal breaks
those with high myopia (myopia - nearsightedness, image is in front of the retina, refractive power is too strong)
61
cxpx of retinal detachment
pt with high myopia/nearsightedness
posterior vitreous detachemt occurs first - flashes and floares
monocular loss of vision eventual that is like a ''curtain drawn down''
SURGICAL EMERGENCY
62
pt with high myopia
expierences flashes and floaters
loss on monocular vision like a curtain drawn down
retinal detachment
| watch out for in diabetics, retinal breaks and inflammatory effusions
63
```
acute
painless
mononuclear vision loss
cloudy retina
cherry red spot @ fovea
```
central retinal artery occlusion
64
how does optic disc appear in central retinal artery occlusion
paalle
| with box car segmentation of blood in retinal veins
65
what causes central retinal artery occlusion
embolus from carotid or ophthalmic artery
| giant cell temporal arteritis involving the ophthalmic artery
66
giant cell arteritis
| emboli
central retinal artery occlusion
67
what is retinitis pigmentosa
inherited retinal degeneration
68
painless
progressive vision loss
starts with night blindness
retinitis pigmentosa
69
what does retina look like in retinitis pigmentosa
bone spicule-shaped deposits around the macula
70
what is retinitis
retinal oedema and necrosis -- leads to a scar
71
what is retinitis associated with
immunosuppression
72
what is retinitis usuallyc aused by
viruses
CMV
HSV
HZV
73
how do you differentiate CMV from HZV retinitis
CMV - ADIS with > 50 CD4/mm and usually painless
| HZV - usually painful.
74
what is papilledema
optic disc swelling
usually bilateral
due to increased icp
75
fundoscopy of papilledema
enlarged blind spot and elevated optic disc with blurred margin
76
retina looks like --> and you think: drusen deposits yellow blobs all over the place between the bruch membrane and retinal pigment epi
dry age related macular degeneration
77
retina looks like --> and you think: hemorrhages, macular edema, new blood vessels and traction
diabetic non and proliferative retinopathy
78
retina looks like --> and you think: retinal hemorrhage and venous engorgement and oedema (Reb blobs everywhere)
retinal vein occlusion
79
retina looks like --> and you think: splaying and paucity of retinal vessels
retinal detachement
80
retina looks like --> and you think: cloudy retina with attenuated vessels and cherry red spot at fovea
central retinal artery occlusion
81
retina looks like --> and you think: bone spicule-shaped deposits around macula
retinitis pigmentosa
82
retina looks like --> and you think: retinal oedema and necrosis
retinitis - scar
83
retina looks like --> and you think: enlarged blind spot and elevated optic disc with blurred margins
papilloedema
84
describe the pathway for miosis
constriction = parasympathetic
edinger westphal nucleus to the ciliary ganglion via CN III
short ciliar nerves to the pupillary sphincter muscles
85
describe how the pupillary light reflex works
CN II from the retina -- to bilateral pretectal nuclei -- stimulate the edinger westphal nuclie bilaterall -- send message via CN III to the ciliary ganglion -- short ciliary out to the pupillary sphincter muscles M3
86
where is the pretectal nuclei
midbrain
87
list the order o the ganglion/nuclei involed int he pupillary light reflex
bilateral pretectal nuclie
bilateral edinger-westphal nuclei
ciliary ganglion
88
describe the physiology of mydrasis
dilation via sympa
first neuron: hypothalamus to ciliospinal centre of Budge at C8-T2
second neuron: exits at T1 to the superior cervical ganglion with the cervical sympathetic chain near the lung apex and subclavian vessles
third neuron: pleusx along the internal carotid - through cavernouso sinus - enters the orbit as long ciliary nerve to pupillary dilator mucles.
89
what do sympathetic fibres do in the eye
long ciliar nere to pupillary dilator muscles
smooth muscle of the minor retractors
sweat gland of forehead and face
90
what are marcus gunn pupils related to pathos wise
multiple sclerosis
| optic nerve damage or severe retinal injuery
91
what tis a marcus gunn pupil
an afferent pupil defect - damage to optic nerve or severe retinal injury - decreased bilateral pupillary constrinction when light is shone in affected eye relative to unaffected eye
92
how do you test marcus gunn pupil
swinging flashlight test
93
slight droppig of eyelid
absence of sweating
flushing
pupil constriction
horner syndrome
anhidrosis
ptosis
miosis
94
what causes horner syndrome
sympathetic denervation of face
95
muscle responsible for slight ptosis in horners
superior tarsal
96
what syndromes are associated with horners?
lesion fo spinal cord above T1
pancoast tumor
brown sequard
late state syringomyelia
97
describe the pathway, along which any disruption can be made to creat horners
hypothalamus - synapse in lateral horn in the ciliospinal center of Budge at c8-t1 --> along the cervical sympathetic chain to the superior cerical canglion at T1 --> plexus along the internal carotid - cavernous sinus - long ciliary to the puplliary dilateor msuceles - alpha 1
98
describe innervation of the EOMs
CN III: IO, MR, IR, SR
CN VI: SO
CN VI: LR
99
what does the superior oblique do
abducts
intorts
depresses when adducted
100
how to test superior oblique
adduct eye (Towards nose) and depress :)
CN IV testin
101
when is the motor output to ocular muscles of CN III affected
central in nerve
affected primarily by vascular disease
ie diabetes mellitus
102
what are signs of motor output compromise to ocular muscies of CN IIII
ptosis
| down and out presentation
103
describe the pathophys of motor output compromise in CN III
vascular disease (ie diabetes mellitus sorbitol accumulation) --> decreased diffusion of oxygen and nutrients to the interior fibres from compromised vasculature that resides on outside of nerve
104
when does the parasympathetic output of CN III become affected?
fibres are on the periphery so are first to be affected by compression
105
when does CN III become compressed
uncla hernation
| pstoerior communicating anuerysm
106
what are signs of parasympathetic output compromise in CN III?
diminished or absent pupillary light reflex
blown pupil
often with down and out
107
describe the diff between CN III motor vrs parasympathetic compromise
motor -- down and out and ptosis
| parasympathetic - absent light reflex and blown pupil (can have down and out too)
108
presentation of CN IV damage
eyes move upwar with contralateral gaze ie adducted (loss of superior oblique)
will also have head tilt towards the side of the lesion
109
if person has problem going down stairs and has compensatory head tilt in opposite direction you think
CN IV
head tilt opposite for stairs
head tilt same side for stare
110
CN VI presentation if damaged
medially directed eye that cannot abduct
| LR gone-zo
111
lesion @ right optic nerve
right anopia
112
lesion @ otpic chiams
bilateral hemoanopsia
113
lesion @ left optic tract
right homonymous hemianopia
114
lestion @ left parietal lobe
right lower quadrantic anopia
115
lesion @ right temporal lobe
left upper quadrantic anopia
116
lesion at right visual cortex
left hemianopia with macular sparing
117
what causes left hemianopia with macular sparing
MCA provides supply to macular region/occipital pole when PCA is occluded causing hemanopia to rest of visual field
118
what does image appear in primary visual cortex compared to real world
upside down
| opposite L-R orientation
119
what causes a central scotoma
macular degemenration
120
what causes central scotoma and metamorphopsia
age related macular degeneration
distortion - metamorphopsia
loss of central visual field - central scotoma
121
describe Meyer's Loop
inferior retina/upper visual field
| loops around inferior horn of lateral ventrcile
122
what is the dorsal optic radiation
superior retina/lower visual field
| takes shortest path via internal capsule
123
what is the medial lemniscus fasciculus
a pair of tracts on the ispilateral side of CN III njuclie and opposite of PPRf and CNVI nuclei that allows for cross talk or CN VI and CN III nuclei
ie coordinates lateral gaze
124
what permits the MLF to communicate very quickly betteen nuclei of CN III and IV
highly meylinated
125
when are bilateral MLF lesions commonly seen
multiple sclerosis - bilaera internuclear opthalmoplegia
126
what is internuclear opthalmoplegia
lesion in MFL
causes conjugate horizontal gaze paralysis
lack of communication so that when CN VI is activated to contract the ipsilateral lateral rectus, the contralateral CNII does not receive stimulation from the MLF (lesioned) to contract the MR by CN II and will instead gaze straight ahead.
127
what happens in internuclear opthalmoplegia when try to abduct eye
get nystagmus bc CN VI is overfiring to stimulate CN III
| frustrated and shaking it around. angry.
128
what happens when looking left :)
CN VI on left is firing to contract the LR on the left. also stimulates the contralateral MLF that then stimulates the CN III to contract MR to look left as well aka adduct
129
what does right INO mean
the right eye is paralyzed and right MLF damaged
| will notice when looking left
