Orbit

Question 1

___ bones make up the orbit

Answer 1

7

Question 2

Describe the orbital margin

Answer 2

• Widest aspect of orbit
• On frontal aspect
• Bounded by frontal bone superiorly, zygomatic bone laterally & inferiorly, & maxilla inferiorly & medially
• Made of 3 bones

Question 3

Describe the apex of the orbit

Answer 3

Tip & posterior aspect of orbit

Question 4

Fat under your eye is called

Answer 4

Periorbital fat

Question 5

Label

Answer 5

1. Frontal
2. Zygomatic
3. Maxilla
4. Ethmoid
5. Sphenoid
6. Lacrimal
7. Palatine

Question 6

Label

Answer 6

1. Zygomatic
2. Periorbita
3. Nasal Cavity
   4, Ethmoid
4. Sphenoid

Question 7

Label

Answer 7

1. Superior orbital foramen
2. Optic canal
3. Superior orbital fissure
4. Inferior orbital fissure
5. Infraorbital foramen

Question 8

What runs through the optic canal?

Answer 8

Optic nerve (CN II)
Ophthalmic artery

Question 9

What runs through the superior orbital fissure?

Answer 9

Oculomotor (CN III)
Trochlear (CN IV)
Ophthalmic branch of trigeminal (CN V1)
Abducens (CN VI)
Ophthalmic vein, sympathetic fibers

Question 10

What runs through the inferior orbital fissure?

Answer 10

Infraorbital nerve (CN V2)
Infraorbital artery

Question 11

How many extraocular muscles do we have?

Answer 11

6

Question 12

Label

Answer 12

1. Superior rectus m
2. superior oblique m
3. superior levator palpebrae m
4. Inferior rectus m
5. medial rectus m
6. lateral rectus m
7. inferior oblique m

Question 13

Label

Answer 13

1. Trochlea
2. Superior oblique
3. Medial rectus
4. Inferior rectus
5. Inferior oblique
6. Lateral rectus
7. superior rectus

Question 14

Function of the tarsal muscle

Answer 14

• Helps keep the eye open
• Helps lubricate eyes
• Provides sympathetic innervation via oculomotor n. In cavernous sinus & superior orbital fissure
• Helps maintain position of the eyeball

Question 15

Define lacrimation

Answer 15

process of producing tears

Question 16

Describe the lacrimal canaliculi

Answer 16

Allows excess fluid to move in, down the lacrimal sac, to nasolacrimal duct & drain under inferior nasal concha

Question 17

What makes up the lacrimal apparatus

Answer 17

Lacrimal canaliculi
nasolacrimal duct
lacrimal gland
inferior nasal concha
nasal cavity
lacrimal sac

Question 18

Label

Answer 18

1. Lacrimal gland
2. Inferior nasal concha
3. Nasal cavity
4. Lacrimal canaliculi
5. Lacrimal sac
6. Nasolacrimal duct

Question 19

Special sensory for the orbit is by

Answer 19

Optic nerve (CN II)

Question 20

General sensory for the orbit is by the Ophthalmic branch of trigeminal. What are the branches?

Answer 20

Lacrimal n., frontal n., nasociliary n.

Question 21

Motor innervation for the orbit is provided by what 3 CN

Answer 21

CN III, IV, & VI

Question 22

What does the Oculomotor (CN III) innervate

Answer 22

Levator palpebrae superioris
Superior rectus
Medial rectus
Inferior rectus
Inferior oblique

Question 23

What does the trochlear n innervate?

Answer 23

Superior oblique

Question 24

What does abducens n innervate?

Answer 24

Lateral rectus

Question 25

Label

Answer 25

1. supraorbital n 2. lacrimal n 3. ophthalmic n 4. Trigeminal ganglion 5. cavernous sinus 6. trochlear n 7. frontal n 8. infratrochlear n

Question 26

Label

Answer 26

1. long ciliary n 2. short ciliary n 3. ciliary ganglion 4. abducens n 5. oculomotor n 6. maxillary n (CN V2) 7. trigeminal ganglion 8. nasociliary n 9. posterior ethmoid n 10. anterior ethmoid n 11. infratrochlear n

Question 27

Label

Answer 27

1. lacrimal n 2. opthalmic n 3. maxillary n 4. rotundum opening 5. pterygopalatine ganglion 6. zygomatic n 7. zygomaticotemporal n 8. communicating branch 9. lacrimal gland

Question 28

Parasympathetic innervation to the orbit. What's their function & muscle involved?

Answer 28

Ciliary ganglion Preganglionic via CN III Postganglionic in short ciliary pupil constriction Contains the sphincter papillae muscle

Question 29

Sympathetic innervation to the orbit. What's their function & muscle involved?

Answer 29

Superior cervical ganglion Internal carotid plexus It comes in along CN V1 & its branches pupil dilation contains dilator papillae muscle & tarsal muscle

Question 30

the lacrimal gland provides secretomotor innervation via

Answer 30

CN VII

Question 31

Label

Answer 31

1. supratrochlear a 2. anterior ethmoidal a 3. posterior ethmoidal a 4. central retinal a 5. ophthalmic a 6. ciliary a 7. lacrimal a 8. supraorbital a

Question 32

Label

Answer 32

1. Ciliary body 2. iris 3. pupil 4. cornea 5. lens 6. suspensory ligament 7. optic nerve 8. optic disc 9. fovea centralis 10. retina 11. choroid 12. sclera

Question 33

retina has a lot of

Answer 33

photoreceptors

Question 34

Describe rod & cone cells

Answer 34

Rod cells: light sensitive, no color, seen in peripheral retina Cone cells: color sensitive, minor light, concentrated in fovea centralis

Question 35

Describe the fovea

Answer 35

center of the retina - highest area of visual acuity

Question 36

What are the intraocular muscles. do they provide parasympathetic or sympathetic?

Answer 36

Sphincter pupillae muscle (parasympathetic) Dilator pupillae muscle (sympathetic) Ciliary muscles (parasympathetic)

Question 37

Define hypotropia, hypertropia, exotropia & esotropia

Answer 37

Hypotropia - 1 eye turns down Hypertropia - 1 eye turns up Exotropia - 1 eye turns out Esotropia - 1 eye turns in

Question 38

Define cataracts

Answer 38

problems w/ light focus due to cell growth, deposits, or protein changes in the lens

Question 39

Define glaucoma

Answer 39

if the vitreous pressure is too high, optic nerve becomes damaged

Question 40

Define aged-related macular degeneration

Answer 40

if the retina fails

Question 41

Define astigmatism

Answer 41

if the cornea is abnormally curved

Question 42

Horner's syndrome is damage to the ___. What 4 things need to be damaged & define them

Answer 42

Sympathetic trunk Ptosis - eyelid drooping Myosis - constricted pupil Anhidrosis - poor sweating Enophthalmos - sunken eye