Review questions Flashcards
(261 cards)
1
Q
Is the cornea vascular?
A
No devascularized
2
Q
Esotropia
A
Cross-eyed
3
Q
Presbyopia
A
far sightedness due to loss of elasticity-usually a result of nuclear sclerosis
4
Q
What happens if CN5 and CN7 are not working properly?
A
no blinking leads to dry eye
5
Q
What should you do in a case of facial nerve paralysis?
A
suture eye shut so eye doesn’t dry out
6
Q
What color eyes have no pigment?
A
blue
7
Q
Define: Heterochromasia
A
eyes of different colors
8
Q
Define: Symblepharon
A
Adhesion and fibrosis of conjunctival ulcerations. Most common cause is neonatal conjunctivitis in kittens
9
Q
What does a blue cornea mean?
A
edema
10
Q
Why is the limbus a common site for rupture?
A
it is a transition area which makes it an area of weakness
11
Q
How many cones do animals tend to have? how about humans?
A
Animals tend to have 2 types blue and yellow-green or purple-blue and green (dichromatic), Humans have Blue yellow-green and red cones (trichromatic)
12
Q
What is the role of the limbus in corneal healing?
A
contains stem cells that aid healing
13
Q
What structure takes up the majority of the eye?
A
vitreous
14
Q
Define: Pannus
A
CMI attack on cornea and uveal antigens. Plasma cells infiltrate cornea
15
Q
Define: Endothelial dystrophy
A
Caused by abnormal nutrition, cornea not metabolizing normally becomes sick
16
Q
What are the 4 layers of the cornea?
A
Epithelium, stroma, descemet’s membrane, endothelium
17
Q
What determines visual field?
A
locationof the eyes, size and shape of the pupil
18
Q
What is the main nerve going to the cornea?
A
CN5
19
Q
What will you find at the healing site of a corneal ulcer?
A
limbal stem cells
20
Q
How do you diagnose corneal ulcers?
A
Flourescein stain. Won’t stain normal retina
21
Q
What does red in the cornea mean?
A
vessels
22
Q
Yellow cornea means:
A
accumulation of cells
23
Q
Dark cornea means:
A
it is ruptured
24
Q
Shiny cornea means:
A
it is thin
25
What happens to the blood vessels of atrophic retinas
They disappear retina reverts to avascular tissue
26
What layer is responsible for most of the corneal thickness?
Stoma-90% of thickness
27
What does white in the retina mean?
abscess or neutrophils
28
Define: Bullous Keratopathy
severe generalized corneal edema. Can triple corneal thickness
29
Where do electrical signals of the eye go to?
Visual cortex-80% of fibers
| Midbrain-20% of fibers
30
What part of the eye receives the most blood flow?
Choroid 85%
31
What forms the diaphragm in front of the lens?
Iris
32
What do animals see when they look at a tv screen. Why?
Bars moving up and down. They have better vision detection
33
Why do predators have more cones?
to have better visual acuity finding prey
34
What determines visual acuity?
number of ganglion cells
35
Define: Limbus
Cornea, conjunctiva and sclera meet at the limbus
36
What part of the eyes are vascular?
choroid, ciliary muscle, iris
37
Corneal Epithelium
outermost layer of the cornea
38
Define: Deep Corneal Ulcers
Exposes the decemas membrane
39
Define: Descemetocele Ulcer
Happens once decemas membrane is exposed
40
Define: Iris Prolapse
Occurs once descemas membrane is broken through. Then the iris comes up to try to plug the hole
41
What causes edema?
a failure in the corneal epithelium pump
42
Define: Sclera
Part of the outer fibrous tunic, supportive structure
43
Does the sclera have vascularization?
Yes
44
Is the Sclera hydrated or dehydrated?
hydrated
45
Define: Glare
condition in which blood vessels in iris start to leak when inflamed. Leak into anterior chamber and vitreous. Cloudiness in aqueous humor.
46
Visual Pathway
axons that form the optic nerve from the right eye go to the left side of the brain and vice versus
47
Reason dog orbit is incomplete?
Allows more jaw opening orbital ligament holds part of the eye. Important during enucleation
48
What kind of animals have complete orbits?
Herbivores
49
What kind of animals have incomplete orbits?
Carnivores
50
What is the inner tunic made of?
Retina
51
Corneal Epithelium Pump
An energy dependent pump whose purpose is to keep the cornea dehydrated
52
Define: Superficial corneal ulcers
affect epithelium only
53
Why would you want to keep the cornea dehydrated?
To keep it clear. Water does not allow it to be clear
54
What is the difference between the collagen patterns of the cornea and the sclera?
In the cornea collagen fibers are organized, in the sclera collagen fibers are disorganized
55
What two structures make up the middle tunic?
Iris and Uvea
56
Define: Retina
Part of the inner tunic. Converts photons to electrical energy. Starts the information processing
57
What is the purpose of the uvea?
acts as a shutter to control light entering the eye
58
What is the Uvea composed of?
Iris, ciliary body, choroid
59
What do zonules do?
They attach to ciliary bodies to help keep the lens in proper position. They are essentially little ligaments that are attached 360 degrees around the eye
60
Are ciliary bodies vascular?
Yes very vascular
61
Which enzyme is inhibited to treat glaucoma?
carbonic anhydrase
62
What enzyme is involved with the production of aqueous humor?
carbonic anhydrase
63
What produces aqueous humor?
cilliary process of the cilliary body
64
Define: Iris
Colored part of the eye
65
Define: Choroid
provides nutrients to the retina. High flow and low oxygen extraction
66
What kind of retinal vascular patterns do dogs and cats have?
Holangiotic
67
Define: Retinal detachment
Occurs between the pigmented layer and the photoreceptor layer
68
What is the most metabolically active tissue in the body?
Retina
69
Define: Fovea
avascular and pigmented
70
Where are the retinal capillaries most dense?
central retina
71
What are rods responsible for?
night vision and motion detection
72
What are cones responsible for?
Day and color vision, visual acuity. Most mammals are dichromatic
73
What are ganglion cells?
axons into the optic nerve
74
What kind of retinal vascular patterns do horses have?
Paurangiotic-very small blood vessesls that are hard to see.
75
Define: Lens
large structure behind the cornea for seeing up close and focusing light rays
76
How does the lens change shape?
through the constriction of ciliary muscles
77
What keeps lens clear?
dehydration
78
What happens when the lens experiences too much dehydration?
The lens can turn opaque
79
What can cause lens luxation?
If the zonules are weak/rupture the lens will shift. Terriers are at risk
80
Define: Glaucoma
Aqueous humor can't leave through the angle, pressure builds up and angle collapses. Persistent pressure can lead to blindness and causes retinal and optic nerve disease
81
What muscles are involved in constricting the pupil?
ciliary muscles
82
Define: Pupil
Hole in the iris that regulates the amount of light getting inside
83
Define: Angle
Where the aqueous humor leaves the eye. Boundary between cornea and iris
84
What is a cataract?
Opacity of the lens or capsule, light is reflected back instead of passing through
85
Define: Nuclear Sclerosis
Age changing in the lens. Animals get it at about 6-7 years of age
86
Accommodation refers to:
the constricting/dilating of ciliary muscles depending on how close/far you need to see.
87
Define: Vitreous
Big space behind lens, in front of the retina
88
Define: Tapetum
Is used for seeing in the dark. Located in the choroid. Not present in all animals
89
Define: Tri-layered Tear film
Lipid-eyelids
aqueous- lacrimal gland and the third eyelid
Mucin-conjunctiva(extremely thin lymph-node)
90
Define: Tear function
Optically smooth surface, provide nutrients for the cornea, corneal immunity
91
What does the Nasal Lacrimal Duct do?
drains tears
92
Define: Epiphora
tears are draining down the face instead of the duct
93
Define: Decussation
Optic Nerve Fibers from right meet left, cross over chiasm
94
menace response
making a motion in front of the eye and having the animal blink
95
What is the purpose of the menace response?
testing vision, learned response
96
Cranial nerve II Optic purpose
for seeing the motion
97
Define: Deturgescence
dehydrate
98
Define: Horner's syndrome
Loss of sympathetic innervation to the eye from otitis chest, neck disease. TE protrusion
99
Define: Haws syndrome
Nictitans protrusion, idiopathic, must rule out the presence of any underlying systemic/ocular disease
100
Define: Miosis
Means pupil is small
101
Reading PLRS
Visual with normal PLR: ok
Visual with absent PLR: efferent problem or pharmacological interference
Blind with normal PLR: something obstructing vision such as cataract
Blind with absent PLR: Problem with retina or optic nerve
102
Cranial nerve VII Facial
In order to blink in the reaction to it
103
Define: Pupillary Light Reflex (PLR)
Shine light at eye and pupil gets smaller (direct), evaluates the peripheral vision, tests retina and oculomotor nerves
104
Palpebral Reflex involves what nerves?
involves cranial nerve 5 and 7
105
Define: Electroretinography (ERG)
Used for evaluating electrical potential of retina in response to light stimulation
106
Define: Mydriatic
Pupil is dilated, retinal disease or optic nerve disease is usually the cause. Glaucoma can also cause it
107
What is the purpose of the third eyelid?
distributes tear film
108
What is the third eyelid made up of?
Covered in conjunctive, made up of gland, ligament, cartilage.
109
How does the third eyelid differ in cats and dogs.
Cats have voluntary control of it
110
Blindness with dilated pupils
Lesion of retina, optic nerve, optic chiasm, or optic tracts before fibers exit to go to the oculomotor nerve. Peripheral blindness
111
Blindness with normal pupils
Lesion of optic tract after fibers exit to go to the oculomotor nerve, optic radiation, or occipital cortex. Central blindess
112
Define: Proptosis
Clinical condition due to trauma, strabismus is a clinical sign
113
Define: Anterior uveitis
inflammation of the iris. Flare, leaky blood vessels due to inflammation , cloudiness in aqueous humor
114
What makes up the uvea?
Iris, ciliary body, choroid.
115
What comprises adnexa? (5)
1. Supporting structures and tissues
2. Orbit
3. Eyelids
4. Third eyelid
5. Nasolacrimal system
116
What nerves are involved with the corneal blind reflex?
A: (CN 5) - Trigeminal
E: (CN 7) - Facial and (CN 6) - Abducens
117
What is the corneal blind reflex?
Stimulation of the cornea = closure of the lids and retraction of the globe
118
What is the orbit?
The bony protection for the globe
119
What are the two main branches of trigeminal that work with the eye?
Ophthalmic nerve, and maxillary nerve
120
What is the innervation for the palpebral reflex?
Afferent arm: CN 5 - Trigeminal n.
| Efferent arm: CN 7- Facial n.
121
What is mydriasis? Sympathetic or parasympathetic?
Large pupil - sympathetic
122
What is miosis? Sympathetic or parasympathetic?
Small pupil - parasympathetic
123
What nerves are responsible for pupillary light reflex?
Afferent arm: retina - CN #2 Optic Nerve
| Efferent arm: parasympatheticfibers along CN #3 oculomotor nerve
124
What is anisocoria?
Unequal pupil size
125
What is the primary purpose of the optic nerve?
Gathers electrical signals from the retina and carries them to the brain.
126
What are the four layers of the cornea?
Epithelium, stroma, descemet's membrane, endothelium
127
What layers does a superficial ulcer go through?
Epithelium, but not into the stroma.
128
What layers does a deep ulcer go through?
Through the epithelium and into the stroma.
129
What layers does a descemetocele ulcer go through?
Goes through all layers except for the endothelium.
130
How does the lens focus light?
By changing shape
131
What is a direct response when concerning the pupillary light reflex test?
When shining a light into a pupil it constricts
132
What is a consensual response when concerning the pupillary light reflex test?
When shining light into a pupil the opposite eye also constricts
133
What is part of the afferent and efferent arms of the parasympathetic pathway?
A: 1. Photoreceptors 2. Optic n. 3. Optic Chiasm 4. Optic Tract 5. Pretectal nucleus
E: 1. Pre-ganglionic fibers 2. Oculomotor n. 3. Parasymp fibers along CN 3 4. Ciliary ganglion 5. Short ciliary nerve 6. Iris sphincter muscle
134
What does visual with normal PLRs mean?
Animal is normal
135
What does visual with absent PLRs mean?
Efferent / Motor problem
136
What does Blind with normal PLRs mean?
Something oscuring vision (cataract ex.)
137
What does blind with absent PLRs mean?
Retina or optic nerve issues
138
What are the nerves involved with Lacrimation?
A: CN V: - Ophthalmic nerve
E: CN 7: - Facial nerve
139
What is the Schirmer Tear Test?
(STT) Hook filter paper over the middle of the lower lid and it assesses tear production.
140
What is innervated by sympathetic fibers?
1. Upper eyelid
2. Dilatory pupillae
3. Third Eyelid
4. Lower eyelid
141
What is the primary purpose of the retina?
It has photoreceptors that when stimulated by light create electrical signals to send to the brain.
142
What layers does an iris prolapse type ulcer go through?
All layers of the cornea.
143
Which layer of the cornea is only one cell layer thick?
Endothelium
144
What do you use to detect ulcers?
Fluorescein stain
145
What does it mean if your cornea is white?
Abscess or necrosis - neutrophils are coming to the damage
146
What is Horner's syndrome?
Sympathetic nerve paralysis
147
What are common causes of Horner's syndrome?
Head trauma, neck trauma, orbit or middle ear issues
148
What eye muscles does Oculomotor nerve (CN 3) innervate?
Dorsal, Central, and Medial rectus muscles. Also inferior oblique muscle
149
What eye muscles does Trochlear nerve (CN 4) innervate?
Superior oblique muscle
150
What muscles does Abducens nerve (CN 6) innervate?
Lateral rectus muscle and retractor bulbi muscles
151
What does it mean if your cornea is blue?
Edema - water inside, endothelium is sick
152
What is lipid keratopathy?
Fat in the eyes. Often associated with a high cholesterol diet in reptiles.
153
What are two things associated with ocular surface failure?
Corneal ulceration and subepithelial keratomycosis
154
What does it mean if your cornea is red?
Vessels in the cornea
155
What is Pannus?
CMI attack on corneal and uveal antigens - worse in young dogs or dogs living at altitude. MHC Class II expression
156
What are the external and internal layers of the retina supplied by?
E: choroidal circulation
I: retinal circulation
157
What are rods responsible for?
Night vision, motion detection
158
What does it mean if your cornea is dark?
The cornea is thin
159
What does it mean if your cornea is shiny? (in animals with tapetum)
The cornea is thin because you see the tapetum reflection really easy.
160
What are the cones responsible for?
Day vision, color vision, visual acuity
161
What is an Electroretinogram?
Recording the electrical activity of the retina after a bright light flash.
162
What is visual evoked potentials?
Recording of the electrical activity of the occipital cortex after a bright light flash
163
Dazzle Reflex Test? Which nerves are involved?
Bright light in front of the eye - Eyelids closure
Afferent Arm: CN#2 Optic Nerve
Efferent Arm CN #6 Facial Nerve
164
What is the PLR (Pulliary light reflex test)? Which nerves are involved?
Bright light in front of eye - pupillary constriction
Afferent: CN #2 Optic Nerve
Efferent: CN #3 Oculomotor Nerve
165
What is the menace response test? Which nerves are involved?
Hand movements in front of eye to see if they blind or retract globe.
Afferent arm: CN #2 Optic Nerve
Efferent arm: CN #7 Facial Nerve, and CN #6 Abducens Nerve
166
What is the autonomic nervous system responsible for? (6)
1. Pupil size
2. Pupillary light response
3. Lacrimation
4. Eye postion
5. Eyelid positon
6. Third eyelid position
167
What is visual placing reaction?
Hold the animal in the air, advance to table, they will extend both forelimbs
168
Dorsal rectus action and innervation?
CN 3 - oculomotor and elevates globe
169
Ventral rectus action and innervation?
CN 3 - Oculomotor and depresses the globe
170
Medial rectus action and innervation?
CN 3 - oculomotor and turns globe nasally
171
Lateral rectus action and innervation?
CN 6 - Abducens and turns globe laterally
172
Retractor bulbi action and innervation?
CN 6 - Abducens and retracts globe
173
Dorsal oblique action and innervation?
CN 4 - Trochlear and intorts globe (inward rotation)
174
Ventral oblique action and innervation?
CN 3 - Occulomotor and extorts globe (outward rotation)
175
What is strabismus?
Lack of parallelism of the visual axes of the eyes.
176
What 3 nerve usually cause strabismus and how does it manifest?
1. Paralysis of Occulomotor - eyes turned laterally. 2. Trochlear - eyes rotated externally, 3. Abducens - eyes turned medially
177
What is nystagmus?
Rhythmical oscillation of the eyeballs
178
Innervation and action of levator palpebrae superioris muscle?
Oculomotor nerve (CN 3) : raises upper lid
179
Innervation and action of Orbicularis oculi muscle?
Facial Nerve (CN 7) : Closes palpebral fissure
180
Can animals see color?
Yes, but colors appear washed out.
181
What is the purpose of the tapetum?
Doubles the probability of absorbency of light by the rods and cones.
182
What does "visual field" i.e. size and shape of the pupil determine?
The angle of which the light can get into the eye, i.e. the angle of the visual field.
183
What does vertical pupils offer for field of view?
Large binocular vision, small monocular vision, large blind spot
184
What does horizontal pupils offer for field of view?
Small binocular vision, large monocular vision, small blind spot
185
What are the layers of the retina? (10) Outer:
1: Retinal pigmented epithelium (RPE) next to choroid
2: Photoreceptor layer (rods and cones)
3. External limiting membrane
4: Outer nuclear layer
5: Outer plexiform layer
6: Inner nuclear layer
7: Inner plexiform layer
8: Ganglion cell layer - axons form the optic nerve
9: Nerve fiber layer
10: Internal limiting membrane - next to vitreous
186
When something goes wrong at which point does it stop being optho and start being neuro?
After the chiasm.
187
What are 4 common problems with vision?
1. Opacity in cornea or lens
2. Lack of retina Fc
3. Optic nerve dysfunction
4. Cortical problems
188
What are three physical dysfunctions of the eye that can cause vision issues (blindness)
Retinal detachment, retinal tear, glaucoma
189
Name four common vision tests
Obstacle course, cotton ball test, visual placing reaction, menace response test
190
Innervation and action of Müller muscle?
Oculomotor nerve (CN 3) ; Raises upper lid
191
What does round pupils offer for field of view?
Medium binocular vision, medium monocular vision, medium blind spot
192
What is descemet's membrane secreted by?
Endothelium
193
Which nerves are the primary nerves for the cornea?
CN5 - trigeminal
194
Are there nerves in decemet's membrane?
NO
195
What are 6 anatomic properties that contribute to transparency of the cornea
1: Lack of blood vessels
2: Lack of pigment
3: Non-keratinized anterior surface epithelium
4: Precise organization of the stromal febrile
5: Small size of the stromal fabrics
6: Relatively dehydrated compared to sclera
196
What are 2 corneal functions?
1: Defection of light - 70% of the eye's refractive or light bending power
2: Transparent to allow light rays to enter
197
What does the epithelium act as a barrier to?
Precorneal tear film
198
How thick is the stromal and is it cellular or acellular?
90% of the corneal thickness is stromal, and it is acellular
199
What is the primary role of the endothelium?
To pump out fluids near the cornea to keep it dehydrated
200
What is the outer coat of fibrous tunics made up of?
Cornea, limbus and sclera --- conjunctiva merges with the epithelial layer of cornea
201
What helps with ulcer healing?
Limbal stem cells
202
What are two functions of the conjunctiva?
Externalized lymphatic tissues
| Produces part of the tear film
203
What are the three layers of conjunctiva?
Epithelial layer, sub-epithelial fibrous layer (Tendon's), Episcleral space (potential space)
204
Which layers of the cornea are most effected by bullous keratopathy?
Anterior stroma, and epithelium
205
What is the limbus?
The transition zone between the cornea and sclera.
206
What are the thinnest parts of the sclera in most species?
Equator and limbus
207
What is the sclera? Is it vascular?
White in color with varying pigment. Sclera is vascular
208
What makes up conjunctival epithelium?
Epithelium from the cornea merges with it.
209
What is the average thickness of a cornea?
0.6mm
210
What is the cotton ball test?
Drop a cotton ball nearby and see if they turn to look at it.
211
Where are other places 20% of the electrical signals go in the brain?
To the midbrain where pupillary light reflex happens
212
What does decussation mean?
Cross over - right eye goes to left side of the brain, and left eye goes to the right side of the brain.
213
How do electrical impulses leave the retina?
Ganglion cell fibers
214
What does facial nerve do?
Motor to eyelids, and other facial muscles
215
What is transduction?
In the photoreceptors when they turn light energy into electrical energy
216
What is a reflex response?
Contains two responses if normal: afferent (sensory) and efferent (motor)
217
What are the four parts of the neurologic system for the eyes?
1. Visual sensory system (Optic Nerve CN #2))
2. Autonomic nervous system (sympathetic and parasympathetic)
3. Oculomotor system: Oculomotor nerve (CN #3), Trochlear Nerve (CN #4), Abducens Nerve (CN #6), and Facial Nerve (CN #7)
4. Trigeminal somatic sensory system (CN #5)
218
What are four functional evaluations that don't necessarily assess vision but test for a faulty mechanism?
Pupillary light reflex (PLR), Dazzle reflex test, electroretinogram (ERG), Visual evoked potentials (VEG)
219
What are the steps of 80% of the electrical pathway from the eyes? (5)
1. Retinal ganglion axons become optic nerve
2. +/- Decussation at the optic chiasm
3. Optic Tracts
4. Ganglion cell synapse in the dorsolateral or lateral geniculate nucleus
5. Output to visual cortex
220
Types of conjunctiva graft (6)
1. Island
2. Bulbar Pedicle
3. Tarsoconjunctival Pedicle
4. Bridge Bulbar
5. Advancement
6. Complete bulbar
221
How much more blood flow is to the ocular region than to the brain?
10 times more to the combined retinal and choroidal regions than that of the brain.
222
What is symblepharon?
Adhesion and fibrosis of conjunctiva ulcerations. Can be caused by infection, chemical injury or trauma. Most common cause is neonatal conjunctivitis in kittens
223
What is another name for severe generalized corneal edema?
Bullous keratopathy - usually edema from trauma
224
What is conjunctivitis?
Inflammation of the conjunctiva
225
What are the external layers of retina supplied by?
Choroidal circulation
226
What are the internal layers of the retina supplied by?
Retinal circulation
227
What is the total ocular blood flow for the retina?
4%
228
What is the total ocular blood flow for the choroid?
85%
229
Is the region that the rods and cones are in vascular?
No, the rods and cones are in an avascular region.
230
What is the path from the globe of the eye to the brain?
1. Exit globe
2. Exit orbit via optic foremen
3. Meets opposite nerve at optic chiasm
4. Continues past chiasm on optic tracts
5. 20% go to pretectal region
6. 80% go to the LGN
7. These axons continue posteriorly to cerebral cortex
231
What does a normal cat retina look like? (3)
1. Circular optic disk lacks myelin
2. 3 major vessels leave the disc at the EDGE
3. Tapetum is usually yellow or green
232
What is PRA?
Progressive retinal atrophy
233
What does a normal dog retina look like? (4)
1. Tapetum - shiny surface
2. Optic disc - white region with vessels on it
3. Retinal vessels - on most of the optic disc
4. Nontapetum - dark region
234
Is the fovea vascular?
No, the fovea is avascular
235
How does the optic nerve exit the eye?
Through the scleral lamina cribosa
236
Which part of the retina has the most dense retinal capillaries?
Central retina
237
What is the optic nerve composed of?
Axons of the retinal ganglion cells, and astrocytes and oligodendrocytes that act as support tissue
238
What does an ERG recording system do?
Measures the electrical responses of the outer retinal layers
239
What is axoplasmic flow?
Transfer of energy and information - interruption can lead to loss of vision!
240
Can the optic nerve be repaired in mammals or birds?
Nope
241
What are clinical signs of PRA? (5)
1. night blindness to total blindness
2. Reduced to absent photoreceptor layer (PLR)
3. Tapetal hyper-reflectivity
4. Retinal vessel attenuation
5. Optic nerve atrophy, +/- cataracts
242
What are some causes for retinal detachment? (5)
1. Trauma
2. Vitreal traction bands - pulls it off
3. Serous effusions - pushes it off
4. Retinal / choroidal / orbital neoplasia
5. Retinal degeneration
243
What are the four retinal vascular patterns?
1. Holangiotic
2. Paurangiotic
3. Merangiotic
4. Anangiotic
244
What is the human retinal circulation pattern?
Single vessels
245
What is LPCA?
Long posterior ciliary artery
246
What is SPCA?
Short posterior ciliary artery
247
Does the choroid have high or low - flow and oxygen extraction?
High flow low oxygen extraction
248
What are the cranial nerves in order?
1. Olfactory
2. Optic
3. Oculomotor
4. Trochlear
5. Trigeminal
6 Abducens
7. Facial Nerve
8. Vestibulocochlear nerve
9. Glossopharengeal
10. Vagus
11. Accessory
12. Hypoglossal
249
Are fovea and peripheral retina vascular or avascular?
Avascular
250
Do retinal vessels have high or low - flow and oxygen extraction
Low flow and high oxygen extraction
251
What is the hyaloid artery?
An artery that extends from the optic disc through the vitreous humor to the lens, which should be regressed before birth.
252
What is the canine retinal circulation pattern?
Multiple vessels that are multidirectional
253
What are the neural systems involved in normal vision and ocular health? (4)
1. Visual sensory system
2. Autonomic nervous system
3. Oculomotor system
4. Trigeminal somatic sensory system
254
What are the innervation types for the cranial nerves?
1. Sensory
2. Sensory
3. Motor
4. Motor
5. Both
6. Motor
7. Both
8. Sensory
9. Both
10. Both
11. Motor
12. Motor
255
Which cranial nerves are associated with eyes? (7)
1. Optic #2
2. Oculomotor #3
3. Trochlear #4
4, Trigeminal l#5
5. Abducens #6
6. Facial #7
7. Vestibulocochlear #8
256
What does optic nerve do?
Sensory - carries visual info from retina to cortex
257
What does oculomotor nerve do?
Motor to several extraocular muscles and levator palpebrae superiors muscle, parasympathetic hitchhikers
258
What does Trochlear nerve do?
Motor to superior oblique muscle
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What does abducens nerve do?
Motor to lateral rectus muscles and retractor bulbi muscles.
260
What does trigeminal nerve do?
Sensory from eyelids, cornea, and lacrimal gland
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What does vestibulocochlear nerve do?
Vestibular component of ocular movements.
