Vision Flashcards
1
Q
Anatomy of the eye layers
A
Fibrous coat ( outermost) Sclera, cornea
Vascular coat (uvea) Choroid, ciliary body, iris
Nervous coat ( innermost) Pigmented layer, retina
2
Q
Job of ciliary body
A
muscle that surrounds the lens
3
Q
what does the choroid do?
A
is at the posterior part of the else. richly vascularlized and provides nourishment to the retina
4
Q
what does the iris do?
A
controls the size of the pupil
5
Q
What condition is possible in the nervous coat layer of the eye?
what is that?
why?
A
Melanoma possible
because of the pigmented layer in the eye
nevous coat is the innermost layer of the eye
6
Q
Optometrist vs Opthalmologist
A
Optometrist
Diagnose and treats eye disease and disorders
Prescribes topical and sometimes oral medication to treat eye disease
Prescribes eyeglasses, contact lenses and vision therapy
don’t require a referal and can send directly to an opthalmologist
Ophthalmologist
Diagnose and treats eye disease and disorders
Surgical and medical management of eye disease and disorders.
require a referal from an MD or an optometrist
7
Q
Most common cause of vision loss in north america?
A
uncorrected refractive error
8
Q
Big 4 causes of vision loss in north america
A
- cataracts
- macular degeneration
- Glaucoma
- Diabetic retinopathy
9
Q
Assessment of visual acuity ?
what is it?
why is it important?
A
measure with eye glasses on - we want to see corrected vision
Acuity = ability to discriminate detail
Useful to establish severity of vision loss in the monitoring of disease
Sudden onset = immediate referral ( blindness. double vision, blurred vision)
Gradual loss = refractive error change or progressive chronic disease
10
Q
When to use the snellen chart? hand held card?
A
SC - 20 feet
HHC - 14 inches ( note it only assesses central vision, not distance)
11
Q
20/20 what does that mean?
20/200?
20/50?
A
20/20 means that someone is reading at 20 feet with others with good vision read at 20 feet
20/200 means that at 20 feet the patient can read print that
a person with normal vision could
read at 200 feet.
also constitutes legal blindness
20/50 minimum driving requirements
you see at 20 what others see at 50 feet
12
Q
what is refraction? why is that important?
A
Refraction: bending of light waves as they pass from one medium to another with different refractive indices
different diopters change the refraction so that eyes that have trouble seeing can see clearly
13
Q
Refractive index
A
Refractive index: ratio of velocity of light in air to the velocity in the substance
14
Q
Diopter
A
Diopter: degree to which a lens bends a light ray; “refractive power”
On opthalmoscope : + diopters are green and are used for patients or self with hyperopia
- diopters are red and used for patients/self with myopia
15
Q
Convex lens does what?
A
converges the light rays
useful for hyperopia
positive diopter corrects
16
Q
Concave lens does what?
A
Diverges the light rays
useful for myopia
negative diopters correct
17
Q
Focal point
A
point at which all rays converge after passing through a refractive medium
18
Q
Focal length
A
distance beyond a lens at which convergence occurs
19
Q
Hyperopia short
A
shorter globe compared to iris
positive diopter corrects - brings focal point closer and on the retina
converge rays
use convex lens
20
Q
Myopia short
A
longer globe compared to iris
negative diopter corrects
diverge rays to get picture further back on retina
use convex lens
21
Q
4 interfaces that make up the lens of the eye
A
(Air) Cornea Aqueous humor Crystalline lens ( anatomical lens) Vitreous humor
22
Q
what is the goal of the lens of the eye?
A
to create a focal point
23
Q
vitrous humour’s job?
A
gel like substance that supports the eye
24
Q
Which nerve moves the lens of the eye?
A
CN 3 - occulo motor
25
what position is the lens in the most relaxed?
contracted?
outside of the eyeball?
relaxed - it's flat
contracted - the cilliary muscles contract and make it more spherical
out of the eyeball the natural shape is round
26
Normal plane of focus in regards to the retina
focal point of the light rays is perfectly on the retina
27
suspensory ligaments of the eye relationship to ciliary bodies
To focus light from a distant object, the ciliary muscles relax. ... To accommodate for a near object, the ciliary muscles contract, thereby decreasing tension in the suspensory ligaments and allowing the lens to spring back into a more rounded shape.
28
Accomodation concept
is an adjustment of refraction
a relaxed eye (distance) rays are paralell
the lens is flat held by suspensary ligaments
focusing on near objects the rays are diverging
ciliary muscles contract, and the lens becomes rounder
controlled by PNS CN 3
29
Hyperopia details (5)
FP? accomodation? globe size? corrected with?
rays/lens?
Difficult accomodation
With lens in relaxed (flat) position, focal point is past the retina and must accommodate even for distance
Becomes too difficult for near vision
shorter globe compared to iris
positive diopter corrects - brings focal point closer and on the retina
converge rays
use convex lens
30
Presbiopia
lens is less elastic, less able to have a spherical shape, less able to accomodate
blurring of near vision with age
31
Myopia - details
FP? accomodation? globe size? corrected with?
rays/lens?
Relaxed lens = focal point in front of the retina
Can’t make lens more flat = no accommodation for distance
As object moves nearer to the eye …
After this point, can accommodate further
myopia occurs when there is alonger globe relative to lens
negative diopter corrects
diverge rays to get picture further back on retina
use convex lens
32
Astigmatism
why?
what?
FP?
Different points of focus from different planes in the lens because of irregular curvature of the cornea
Accommodation will be too much in one plane or not enough in another, and good in another
focal point in multiple areas of the retina (front or behind)
33
irregular curvature of the cornea causes what?
astigmatism
34
What is the crystaline lens?
tissue?
shape?
controlled?
Anatomical lens of the eye. Adjusts for accomodation ( near vision)
made of avascular epithelium ( enclosed in a capsule - no vacular supply)
normally spherical / convex
controlled by CN and the suspensory ligaments ( controlled by ciliary muscles)
35
Cataract?
what?
presentation?
risks?
Congenital or acquired lenticular opacities
Deposition of protein in the lens
lens looks opaque
(accumulation of epithelial cells that were sloughed off with no where to go)
this is a pathology but rooted in normal process
risks : age, poorly managed diabetes, age are the main ones
36
dirty window analogy ( for the eye)
the lens is like a window, when clear light can shine through and hit the optic nerve producing visual stimuli ; however, when the window is dirty such as in cataracts, it is cloudy and the visual acuity may not be present.
may still be light sensitive
37
Cataract presentation (5)
Blurring of vision gradually
tinting of lens ( change in colour vision)
Glare or halos
Poor night vision
No pain
38
what does melanin do in the eye?
special population to consider?
stops light from bouncing around by absorbing it and prevents reflection
albino populations generally have reduced visiual acuity b/c rays bounce around inside of the eye due to decreased melanin
39
What creates the red reflex in the eye?
what might interfere?
reflection of vascular tissue in the retina and choroid ( is the vascular layer of the eye, containing connective tissues, and lying between the retina and the sclera.)
abscence of the red reflex may be due to cataracts, less commonly detached retina or retinoblastoma (cancer)
40
what is the choroid?
is the vascular layer of the eye, containing connective tissues, and lying between the retina and the sclera.
41
Light sensitive receptors
Most concentrated on the fovea at the focal point
Rods : dark vision and peripheral vision
Cones: colour vision, acute vision
42
Nervous layer of the eye
Light sensitive receptors : rods and cones
excited by light rays, AP transmitted via neurons to CN 2 and occipital cortex
Maximum visual acuity; <2° of visual field
Gradual decrease in acuity towards periphery
43
Fovea and Macula
highest concentration of cones
acute central vision
44
Maximum visual acuity is where? why?
Maximum visual acuity; <2° of visual field
Gradual decrease in acuity towards periphery
b/c of the shape of the eye - doesn't get light so no need for photoreceptors
45
Features of the retina ( structures ) 4
Macula and fovea
optic disc
no lymph drainage
blood supply
46
Optic disc
Site of optic nerve head, central artery and vein
| “Blind spot”
47
Is there lymph drainage in the retina?
no lymph
the vitrous humour picks up the waste
48
Why when doing an ophthalmic exam, we enter the eye at 15 degrees temporal instead of straight on?
To get a clear view of the optic disk to orient ourselves
49
ARMD
what?
risks?
Age-Related Macular Degeneration
Deterioration of the macula ; therefore, colour and central vision ( acuity)
Risk factors:
Age
Smoking … oxidative damage?
Genetic
50
Where does ARMD target?
RPE + Bruch membrane + choriocapillaris (The capillary lamina of choroid)
=
Functional layer
51
What is VEGF? what does it do?
Vascular endothelial growth factor (VEGF), is a signal protein produced by cells that stimulates the formation of blood vessels.
52
2 types of ARMD
Non-neovascular (atrophic, dry)
- drusen
Neovascular (exudative, wet); 10-20%
- leaking, hemorrhage etc.
53
Non-neovascular
| ARMD (specifics)
Non-neovascular (atrophic, dry) ARMD
Deposits (drusen) in Bruch membrane (Bruch's membrane is the innermost layer of the choroid. It is also called the vitreous lamina, because of its glassy microscopic appearance.)
and geographic atrophy of the RPE (retinal pigment epithelium)
Secretion of inflammatory cytokines and recruitment of VEGF = angiogenesis
54
What is Bruch's membrane? what part of the eye is it in?
Bruch's membrane is the innermost layer of the choroid. It is also called the vitreous lamina, because of its glassy microscopic appearance.
55
Neo vascular ARMD
Neovascular (exudative, wet); 10-20%
Choroidal neovascular membranes penetrate Bruch membrane, possibly RPE
Leaking, hemorrhage --> macular scarification
Can cause retinal detachment
56
ARMD presentation (3)
Loss of central vision; gradual change
Difficulties with night vision
Painless
57
Amsler Grid and relevance
cover one eye and stare at the black dot
someone with ARMD , the lines pattern may appear wavy or some of the lines may be missing or broken
58
What is the aqueous humor? 4
secreted by what/ flow?
part of the lens system
Clear, free flowing fluid
Continually formed and resorbed
Supports wall of eyeball; nourishes cornea and lens; drains metabolites
Secreted by ciliary processes into posterior chamber --> bathes lens --> moves through pupil to anterior chamber --> resorbed via trabecular meshwork --> canal of Schlemm
(front of lens and back of iris --> through pupil and ant iris back of cornea)
59
Glaucoma prevalence
prevention?
2nd leading cause of blindness
most prevalent is primary open angle
not preventatble but treatment delays progression
60
Open Angle Glaucoma generals
there us resistance to the aqueous flow which increases the intra-ocular pressure
61
Primary open angle glaucoma 4
most common
aqueous humor has physical access to the trabecular meshwork but there us resistance to the aqueous flow which increases the intra-ocular pressure
normal depth of anterior chamber
obstruction distal to anterior chamber angle
62
Secondary open angle glaucoma
due to clogging of trabecular meshwork with debris which strains the mechanism and the flow of aqueous humor
63
Angle closure glaucoma primary
shallow anterior chambers
Apposition of periphery of iris to lens (pupillary block) with pupil dilation
genetic/anatomical, less common
Elevated pressure in posterior chamber
Apposes iris to trabecular meshwork
Chronic elevation in IOP can lead to acute elevation
64
Angle closure glaucoma secondary
due to neovascular changes associated with diabetes
| Formation of contractile membrane over iris which occludes trabecular meshwork
65
Secondary ACG special considerations
poorly managed diabetes : VEGF is pumped out in the iris and new blood vessels are formed
slow chronic elevation of pressure with accute dilation - immediate increase in pressure can be painful
66
Glaucoma Generals (9)
Retinal changes
1. Compression of optic nerve and retinal artery
2. Obstruction of axonal cytoplasmic flow,
3. ischemia of ganglion cells ( decrease nutrient transport to the optic nerve)
4. Cupped and atrophic optic nerve head
5. Increased “cup-to-disc ratio”
6. Necrosis of retinal nerve cells
7. Thinning of retina
8. Focal scleral thinning
9. Lens opacities due to lack of nutrition
67
What is a normal cup to disc ratio?
relevance?
Glaucoma
should be less than 1/3-1/2
68
Open angle glaucoma presentation
Open angle = slow progression
Loss of peripheral vision (“tunnel vision”)
No pain
69
Closed angle glaucoma presentation
symptoms
Closed angle = slow progression until acute, rapid rise in IOP (rare) due to pupil dilation
Emergent; blindness within 24 hours
```
Symptoms:
Typically unilateral
Blurred vision, halos, tunnel vision
Red, painful eye; headache
Headache, photophobia, nausea, vomiting (what does this sound like?)
```
70
Why would a patient with mild symptoms of glaucoma improve in a bright room?
because the pressure is increased, so when the pupil is dialated in a dark room, it puts pressure on the eye while a bright room makes it better
71
How are field of vision defects different from glaucoma?
field of vision defects usually pertain to full or 1/2 of vision changes in the nasal or temporal regions and are idfferent in each eye.
glaucoma the peripheral vision is lost
72
Testing for POAG - 6
```
No method (in primary care) has very good sensitivity; no good screening methods
Regular annual eye exams advised over 40; more frequent or earlier if high risk
```
Tonometry = measuring IOP
Fundoscopy aka Ophthalmoscopy
Fundus photography
Thickness of optic nerve fibres
Visual field testing
73
Tonometry
Tonometry = measuring IOP
Cornea anesthetized
Apply pressure to cornea
Amount of corneal displacement measured
Reflects intraoccular pressure
74
Assessing for shallow angles?
relevance?
we should be able to illuminate the iris on the other side
if the shadow is cast, it shows a very narrow anterior chamber in a patient with ACG
75
Areas affected in the diabetic eye? 5
```
lens
iris
ciliary body
retina
optic nerve
```
76
Causes of diabetic neuropathy
elevated blood sugar
sugar molecules attaching to other RBCs, immune cells etc that they aren't supposed to ( Production of advanced glycosylated end products)
77
prevalence of diabetic neuropathy?
very common - the higher the blood sugar in both type 1 and type 2 the increased risk for diabetic retinopathy
78
Background Retinopathy 3
aka : non-proliferative retinopathy
1. Thickening of endothelial basement membrane
Formation of microaneurysms and microhemorrhages
2. Increased permeability of retinal endothelia
Macular edema
Exudates
3. Micro-occlusion : (small thrombi restrict acess of blood to tissue) no new neovascularization
79
Proliferative neuropathy
Characterized by neovascularization
A web of vessels form a contractile neovascular membrane
leaky vessels
secretion of VEGF increases angiogenesis
predisposes for a retinal detachment
late complication of diabetes
80
In which conditions is there formation of a neovascular membrane?
what is it?
Proliferative retinopathy
Secondary Closed Angle Glaucoma
new dmaaging blood vessels that grow beneath the retina
81
Vision of a person with diabetic neuropathy
depends on the person and specific to their manifestation
no characteristics
82
Arteriosclerosis of the retina
Arteriosclerosis = thickening
Vessels are narrower
Colour of blood column changes --> copper, silver
Compression of paired venule --> “nicking”
Exudate into retina
Possible hemorrhage
Focal ischemia and infarcts --> “cotton wool spots”
normal arteries = nice and thin
83
What condition happens with arteriosclerosis of the retina?
and keynotes 4
Hypertensive retinopathy
- blood column changes to copper or silver
- venule compression " nicking"
possible hemmorhage
exudates ( cotton wool spots)
84
Why are arterioles in the eye thickened? what is this called?
tortuous blood vessels
due to arteriosclerosis of the retina/ hypertensive retinopathy
85
What are cotton wool spots?
relevance
which condition(s)?
microinfarct
hard to tell the difference if it's CWS or exudate
relevance :
hey are caused by damage to nerve fibers and are a result of accumulations of axoplasmic material within the nerve fiber layer.
diabetes mellitus, systemic hypertension, and acquired immunodeficiency syndrome
86
Red flags for vision patient 6
Sudden vision loss or change
other indicators of urgency ( with or w/o vision loss) :
```
Pain
Double vision
Sudden blur
Flashing lights
Floater onset
```
87
Vitreous humor
what?
job?
pathologies?
transparent gel
nutrient and waste management system
holds globe of the eye open
supports posterior surface of the retina and and pigmented layer ( keeps close contact)
vulnerable to opacification
88
How common is retinal detachment?
2/10 000 people a year
emergent - don't miss
89
What is retinal detachment?
Separation of neurosensory layer from pigmented epithelium; ischemia and necrosis of photoreceptors
Medical emergency!
90
Causes of retinal detachment?
3
increased risk? 3
trauma, inflammation, contracture (shortning) of vitreous humor
increased risk with age, myopia, and F&PH
91
Rhegmatogenous detachment
more common
Separation of neurosensory retina from pigmented epithelium with a full-thickness retinal tear
Often subsequent to posterior vitreous detachment causing traction on the retina (occurs with aging)
Vitreous humor enters potential space between the pigmented epithelium and neurosensory retina and separates them
92
Consequences of a Rhegmatogenous detachment
a detachment with tear, a tear in the retina allows seepage through the tear of liquefied vitreous humor, which accumulates beneath the retina and pushes it away
longer for nutrients to travel and results in necrosis
93
Non-rhegmatogenous detachment
No retinal defect
Associated with vascular disorders causing exudation into subretinal space
Inflammation and damage of the RPE
Leaking of exudate from choroidal circulation
94
Non-rhegmatogenous detachment consequences 2
In a detachment without tear, the retina is pulled away by conditions in the vitreous humor.
vascular disorder
blood vessels coming up into that space
95
Retinal detachment presentation
most likely due to?
and what to do if you see symptoms?
Painless!
Acute-onset unilateral floaters, flashers
Sudden and progressive monocular vision loss
Sensation of a veil over one field of view (FOV)
Location depends on location of tear
Apparent curving of straight lines
(Vitreous hemorrhage or pigmentation on slit light exam)
Most likely due to posterior vitreous detachment, but can lead to retinal tears
Refer immediately for dilated exam!
96
What chronic conditions can predispose to or cause retinal detachment?
What are the mechanisms for this?
look up *
97
rippling of retinal surface is due to what condition?
Rhegmatogenous retinal detachment.
In the picture:
The inferior temporal portion of the retina is detached and the subretinal fluid makes visualization of the pigment epithelium and choroid relatively difficult.
98
Floaters and flashers are major warning signs of what?
Rentinal Detachment - but can happen with other conditions too such as trauma
99
What is the cornea?
what does it do?
what kind of tissue?
vulnerable to what?
Transparent anterior component of fibrous coat
Junctions with sclera
Major refractive surface of the eye
Shape will impact ability to focus directly on retina
Epithelial surface, avascular
Vulnerable to keratinization, scarification
Dramatic changes to refraction and vision
100
Is the cornea vascular? why or why not?
Not vascular - if it was it couln't be transparent and it is part of the lens system
101
Corneal abraison
presentation
```
eye pain
redness
tearing
decreased vision
increased inflammation response
sensation of foriegn body in the eye
```
102
Corneal abraision consequences and diagnosis
permanent change in vision possible if the healing results in scarring or keratinization
utilizing blue setting on the opthalmoscope
103
CN 2
describe?
what would you see in a pathological situation?
Optic Nerve
Snesory tract of CNS - leads to vision
surrounded by meninges and CSF
subject to CNS lesions
ie) lesion of the optic nerve, we need to consider tumor, etc.
you would see a protruding optic disc with increased ICP
104
What is optic neuritis?
what condition is this common in?
Inflammation of the optic nerve
Swelling of optic nerve head = “papilledema”
Blurred disc margins
common in MS
demylination is due to inflammatory changes
105
Optic neuritis in MS
Describe MOA and symptoms
demylination due to inflammatory changes
may involve extra-occular muscles
swelling of the optic nerve head (papilledema)
may be severe to permanently damage the nerve
106
What happens when there is inflammation behind the eye that you don't seee it in an eye exam?
what might we see?
there may be swelling of the optic disc - we don't see well defined borders
it may be red and inflammed
107
what is papilitits?
swelling associated with the optic disc
108
What is Retinal artery occlusion?
Embolus/thrombus of central retinal artery or branch
sudden onset of painless vision loss
Distal ischemia = diffuse or segmental infarct
see : cherry spot ( b/c everywhere except the fovea is swollen)
109
What is the characteristic presentation of acute retinal artery occlusion? (6)
sudden onset of painless vision loss
Classic Cherry red spot :
Acute swelling of neurosensory layer blocks view of vascular choroid
opacity of retina is enhanced (more cloudy
Fovea is excepted “cherry-red spot”
can't see the red reflex
the eye is not supplied with sufficient oxygen
110
What other condition can we compare a retinal artery occlusion to? why?
A heart attack
there is an ischemic (restriction of blood supply) change which causes tissue necrosis
typically acute
111
What does red eye signal?
most common cause(s)?
sign of inflammation via cytokines, dilation or rupture of blood vessels
most often benign due to conjunctivitis
112
Urgent red eye scenarios? 9
1. Acute closed-angle glaucoma
2. Optic neuritis
3. Trauma,
4. corneal penetration,
5. blood in anterior chamber
6. Orbital cellulitis
7. Scleritis
8. Anterior uveitis
9. Infectious keratitis (HSV, VZV)
113
Short
Orbital cellulitis?
cellulitis - bacterial skin infection
may cause red eye
114
short - Scleritis?
threatens vision
Severe, boring pain radiating to periorbital area; pain increases with eye movements; ocular redness; watery discharge; photophobia; intense nighttime pain; pain upon awakening
115
episcleritis vs scleritis?
epi - red eye, superficial vessels of the eye doesn't affect vision
scleritis - threatens vision - very painful
116
Systemmic conditions associated with red eye ( some)
```
Graves
Sjogren
Rheumatoid arthritis
Reiter syndrome
Lupus
Polyarteritis nodosa
HIV
Diabetes mellitus
```
117
Red flags with red eye
pain and red eye major red flag
118
Diabetes and red eye
MOA and clinical presentation?
poorly managed blood sugar and high cholesterol can result in micro occlusions, rigidity, leakiness etc.
widespread damage to vasculature which includes the eye
clinically we might see cotton wool spots
119
Which factors do we assess for urgen eye exam?
why **
Cornea (use fluorescein staining)
- to see if there is abrasion
Pupils (size, shape, reaction to light, symmetry)
issues with CNs, etc.
Anterior chamber (clarity) and iris
Hyperemia (location and pattern)
- changes in blood flow and how that affectst the body
ie) occlusion
120
The aperture of the eye is what?
the pupil
121
The aperture of the eye is controlled by what?
what does it do?
abnormalities?
CN 3 - PNS
contracts and dilates in response to light - accomodation (PERLA)
Abnormals in drug use, head trauma, systemic conditions : blocked transmission of visual signals from the retina to the optic centers of the brain
122
PERLA
Pupils and Equal and Reactive to Light and Accomodation
123
Ways to evaluate the pupil ( 3 exams)
Size, shape and symmetry
miosis ( excessive contriction?)
mydriasis ( dilation of the pupil?)
Reaction to light?
- Direct or consensual
Near reaction
124
Near reaction - who cannot do this?
people with hyperthyroidism - specifically graves disease
125
Consensual and Direct Pupillary light reflex findings
Consensual - responds to light on the opposite side as it shines
Consensual may be present if light is shone into good eye, may show up ion blind eye but not vice versa
occulomotor nerve
126
Acute conjunctivitis : what would you see on the eye?
Global injection pattern - very red sclera of the eye.
blood vessels excentuated
127
Subconjunctival hemorrhage : what would you see on the eye?
The extravasated blood has completely obscured the sclera underneath. Note the slightly raised appearance of the affected area.
very red
128
Scleritis : what would you see on the eye?
Diffuse scleritis with a violaceous hue caused by deep inflammation.
Vessels do not blanch
129
epicleritis : what would you see on the eye?
redness on only the most superficial vessels of the eye
130
Acute angle closure gluacoma : what would you see on the eye?
Eye that does better in a bright room
may be red, cloudy pupil or cornea, dilated pupil in normal light
131
Anterior uveitis : what would you see on the eye?
Note the perilimbal injection ( all over red vessels)
and the irregularly shaped pupil.
direct and consensual photophobia
132
Extraoccular Muscles and Innervations
LR 6 SO4
Superior Oblique (4) (down towards nose) and Infectior Oblique (3)
Medial rectus (3) and lateral rectus (6) (out)
Superior and inferior rectus (3)
133
Biggest risk factors for primary open angle glucoma AMA
high myopia, increased CDR, family history, black race, increasing age, presence of dic hemorrhage
low IOP makes glucoma unlikely
134
T or false
Glaucoma is an optic neuropathy characterized
by irreversible loss of retinal
ganglion cells, resulting in progressive
thickening of the retinal nerve fiber
layer. It is often associated with higher
IOP
False :
to do with the thinning of retinal nerve fibers
135
How to differentiate closed and open angle glaucoma AMA?
open-angle and closed-angle forms
based on the morphological appearance
of the iridocorneal angle at which
aqueous drainage takes place.
136
T or false normal IOP is less or equal to 21 mmHg?
True
137
What gives glaucoma it;s characteristic appearance of optic nerve cupping and increased CDR?
The loss of retinal nerve (ganglion) fiber layer tissue
138
T or False
Progrssive loss of retinal ganglial cells causes peripheral vision loss?
Yes, in glaucoma
139
T of False
```
Glaucoma was defined by the presence
of an optic disc with changes characteristic
of glaucoma that could not be explained
by another cause with a corresponding
visual field abnormality.
```
True
140
T or False
Increased cup to dic ratio is present in diabetic neuropathy?
false
141
True or False
CDR is measured by size, asymmetry, dic hemorrhages, IOP, and patient reported vision loss
False
not reported vision loss
142
T or F
POAG is the second most dominant form of gluacoma in North America
False - it is the second leading cause of blindness worldwide
primary form of glaucoma in NA
143
T or F
| Increased CDR should always warant a referral to an opthamologist?
true - for glaucoma assessment. If they already know then no
144
Most common cause of red eye?
conjunctivitis
145
Common causes of red eye
Conjunctivitis is the most common cause of red eye. Other common causes include blepharitis,
corneal abrasion, foreign body, subconjunctival hemorrhage, keratitis, iritis, glaucoma, chemical burn, and scleritis.
146
Signs and symptoms of red eye
include eye discharge, redness, pain, photophobia, itching, and visual changes
147
When is a referral for red eye needed (10)
OUCM
Referral is necessary when 1. severe pain
is not relieved with topical anesthetics;
2. topical steroids are needed;
3. the patient has vision loss, 4. copious purulent discharge,
5. corneal
involvement,
6. traumatic eye injury,
7. recent ocular surgery, 8. distorted pupil,
9. herpes infection,
10. or recurrent infections.
148
Causes of conjunctivits (4)
viral , bacterial, chlamydial, noninfectious ( allergies)
149
Which virus is the most virulent in viral conjunctivits?
Adenovirus
150
Categories of bacterial conjunctivits
hyperacute - neisseria gonorrhoeae ( sexually active adults)
acute - most common. stap aureus,(adults) strep pneumoniae (children)
chronic - sx last for 4 weeks
151
Herpes zoster conjunctivitis
signs (3)
symptoms
Vesicular rash, keratitis, uveitis
Pain and tingling sensation precedes
rash and conjunctivitis, typically
unilateral with dermatomal
involvement (periocular vesicles)
152
Viral conjunctivits
signs (3)
symptoms 2
normal vision
redness
preauricular lymphadenopathy
Symp : mild/no pain
often unilateral
153
Bacterial Conjunctivits
signs 1
symptoms (4)
eyelid edema
symp: mild to moderate pain - stinging
red eye with foriegn body sensation
purulent discharge
glued eyes upon waking
154
Aleergic conjunctivits
signs 1
symptoms (5)
Visual acuity preserved
```
bilateral
painless tearing
very itchy
red
watery discharge
```
155
Keratoconjuctivits sicca
signs 2
symptoms (7)
Dry eye
vision usually preserved
```
bilateral
red
itchy
foreign body sensation
mild pain
intermittent excessive watering
```
156
Blepharitis
signs 3 , symp, 4
Dandruff like scaling on eyelashes
swollen eyelids
leads to conjunctivitis
red
irritated eye
worse when waking
crusty eyelids
157
Corneal abrasion
signs 3, symptoms,
corneal edema or haze
foriegn body sensation
may have decreased visual acuity
severe eye pain
red
watery eyes
158
Subconjunctival hemorrhage
signs 2 symptoms 3
signs - normal vision
bright red patch
white sclera
mild to no pain
no visual disturbance
no discharge
159
Episcleritis
signs 1 symptoms 1
vision preserved
confined red patch on outer vessels of the sclera
vision preserved
160
Keratitis
signs 1 symptoms 4
diminished vision
painful red eye
diminished vision
mucopurulent discharge
bacterial origin
161
irits
signs 3 symptoms 3
diminished vision
poorly reacting pupils
constricted pupils
constant eye pain
watering red eye
photophobia
162
ACAG
| signs 4 symptoms 1
reduction in visiual acuity
dilated pupils
diffuse redness
halos appear when patient is around lights
acute onset of severe throbbing pain
163
Scleritis
| signs 1 symptoms 1
diminished vision
severe pain radiating to preorbital area
164
dry eye
aka
associated with what?
keratoconjunctivitis sicca
increased age, female, and anticholinergics
165
what constitutes serious eye disease? 4
red eye, photophobia, visual blurring, and eye pain
166
What is ansiocoria?
a test - smaller pupil in the red eye and difference in pupil diameters
167
Serious eye diseases ( 4)
uveitis
keratitis
corneal abrasion
scleritis
168
Bengin disorder of the conjunctiva
conjunctivitis
episcleritis
subconjunctival hemorrhage
169
Diagnostic score for bacterial conjunctivitis
(Rietveld)
what are we testing for?
what score do we need?
```
2 glued eyes in the morning
plus 5 points
1 glued eye in the morning plus 2 points
Itching minus 1 points
History of conjunctivitis minus 2 points
```
score of 4 increases the probablity of bacterial conjunctivists
170
Strabismus
what?
history?
PE?
next step?
most common cause of vision loss in children
2 eyes do not point in the same direction
history:
family reports childs eyes cross
PE: extraoccular movement abnormal
cover/uncover test positive
refer to opthamologist
171
Amblyopia
what?
history?
PE?
next step?
most common cause of vision loss in children
lazy eye - reduced visual acuity in 1 eye
not correctable with lenses
history of premature birth
down syndrome, CP
vision decreased in 1 eye
refer
172
How to test for refractive errors?
we don't but can use snellen, or refer
173
Optic nerve hypoplasia
what?
history?
PE?
next step?
non-progressive disorder
history of vision loss
central vision but no peripheral vision
Optic never is 1/2-1/3 normal size
pale grey
surrounded by halo
refer
174
Retinoblastoma
what?
history?
PE?
next step?
intraocular tumor of childhood
Family history
child up to 2 years old
absence of red reflex/partial
strabismus
white flat masses on the retina
refer - can spread to brain or BM
175
What is retinopathy?
a disease of the retina which causes vision loss
176
Nystagmus
history?
PE?
next step?
histroy of eyes searching
rapid movement of eyes
refer
177
Uveitis
what?
history?
PE?
next step?
inflam activity of iris, ciliary body, and choroid
History of chronic inflammation
mild to moderate pain
photophobia and tearing
PE - varied
refer - severe condition
178
Optic Nerve Glioma
dimness of vision, loss of fields
unilateral vision loss with pain
```
visual fields compromised
optic atrophy (decline)
```
very associated with neurofibromatosis
179
Craniopharygioma
what?
history?
PE?
next step?
tumors from the squamous epithelium of the brain
history :
HA, visual disturbance,
PE: increased IC pressire
normal optic discs
refer
