Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

ANATOMY - head, neck & spine > L13 bony orbits and eye movements > Flashcards

L13 bony orbits and eye movements Flashcards

1
Q

what 7 bones contribute to the orbital cavity?

A
  1. orbital plate of** ethmoid**
  2. sphenoid
  3. orbital surface of maxilla
    4.** zygomatic** bone
    5.** lacrimal **bone
  4. palatine bone
    7.** frontal** bone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what bones make up the roof of the orbit?

A
  • orbital plate of frontal bone
  • lesser wing of sphenoid bone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what bones make up the floor of the orbit?

A
  • orbital surface of maxillary bone
    * zygomatic bone
  • orbital surface of **palatine bone **
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what bones make up the** lateral wall** of the orbit?

A
  • **greater wing **of sphenoid bone
  • orbital surface of **zygomatic bone **
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what are the foramina / fissures of the orbit?

A
  • superior orbital fissure
  • inferior orbital fissure
  • optic canal
  • infraorbital foramen
  • supraorbital foramen
  • infra orbital groove
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what bone that makes up the roof of the orbit separates the orbit from the anterior cranial fossa?

A

the frontal bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what bone that contributes to the floor of the orbit seperates the orbit from the underlying maxillay sinus?

A

the maxilla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what bones make up the medial wall of the orbit?

A
  • the ethmoid
  • maxilla
  • lacrimal
  • sphenoid bone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what are the** contents of the orbit**?

A
  • eyeball
  • fascia
  • muscles
  • vessels
  • nerves
  • lacrimal gland
  • orbital fat
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what vessel does the eye primarily receive blood from?

A

the ophthalamic artery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what veins drain the orbit?

A

venous drainage via the superior and inferior ophthalamic veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what **cranial nerves **supply the eye and its structures?

A
  • optic nerve
  • oculomotor nerve
  • trochlear nerve
  • trigeminal nerve (via ophthalmic nerve branch)
  • abducens nerve
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is the function of the orbital fat?

A

it cushions the eye and **stabilises extraocular muscles **

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what are the 3 main foramina by which structures can enter and leave the orbit?

A
  1. optic canal
  2. superior orbital fissure
  3. inferior orbital fissure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what** 3 structures **(2 vessels and 1 nerve) pass through the optic canal?

A
  1. optic nerve (CNII)
  2. Opthlamic artery
  3. central retinal vein
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what region of the orbit does the ophthalamic artery supply?

A

the **medial wall **of the orbit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what is the function of the central retinal vein?

A
  • drains blood from capillaries of retina into the superior opthalamic vein or cavernous sinus directly
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what** 8 structures** pass through the superior orbital fissure?

A
  • cranial nerve III,IV,VI
  • **lacrimal nerve **- CNV1
    * frontal nerve - CNV1
  • Nasociliary nerve - CNV1
  • orbital branch of middle meningeal artery
  • recurrent branch of lacrimal artery
  • superior orbital vein
  • superior opthalamic vein
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what are the** cavernous sinuses**?

A
  • one of the dural venous sinuses of the head
  • network of veins that sit in a cavity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what 2 structures does the superior orbital fissure connect to?

A
  • cavernous sinus
  • intracranial space
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what structures pass through the** inferior orbital fissure**?

A
  • infraorbital nerve
  • maxillary nerve (branch of CN V)
  • zygomatic nerve
  • parasympathetics to lacrimal gland
  • infraorbital artery
  • infraorbital vein
22
Q

what are other minor openings into the orbital cavity?

A
  • the nasolacrimal canal - drains tears from eye to nasal cavity
  • supra orbital foramen and infraorbital canal - carry small neurovascular structures
23
Q

what are the** extrinsic muscles of the eye** called?

A

extraocular muscles

24
Q

what are the intrinsic muscles of the eye called?

A

intraocular eye muscles

25
what are the** 7 extraocular muscles** ?
* 4x **rectus muscles **(superior, inferior, lateral, medial) * 2x **oblique** (superior , inferior) * 1 x **levator palpebrae superioris **- elevates eye lid
26
what is the annulus of zinn?
* some of the extraocular muscles either originate from the bony orbit or the **common tendinous ring (annulus of zinn)** and insert at specfic areas of the eye ball
27
what kind of movement of the eye does the medial rectus carry out?
adduction
28
what kind of movements of the eye does the **lateral rectus** muscle carry out?
abduction
29
what 2 kind of movements of the eye does the **superior rectus** carry out?
* elevation * adduction
30
what kind of movements of the eye does the **inferior rectus **carry out?
* depression * adduction
31
what 3 kind of movements of the eye does the **inferior oblique** muscle carry out?
* extorsion * elevation * abduction
32
what 3 kind of movements of the eye does the superior oblique muscle carry out?
* introsion * depression * abduction
33
what **4 extraocular muscles o**riginate from the** common tendinous ring**?
* medial rectus * lateral rectus * inferior rectus * superior rectus
34
what cranial nerve innervates the lateral rectus muscle? RECAP
CN VI - Abducens nerve
35
where does the **inferior oblique **muscles **originate from**?
anterior orbital surface of maxilla
36
where does the superior oblique muscle originate from?
the sphenoid bone
37
what effect does the sympathetic outflow have on the pupil?
causes pupil dilation
38
what effect does the parasympathetic outflow have on the pupils ?
causes pupil constriction - via oculomotor nerve
39
what are the 3 intraocular muscles?
* sphincter pupillae - parasympathetic innervation * dilator pupillae - sympathetic innervation * cilary muscle
40
what is the **function of the intraocular muscles**?
they control the movement of the lens and pupil and therefore participate in the accomodation reflex
41
what cranial nerve innervates the superior oblique muscle?
CN IV - Trochlear nerve
42
what **3 cranial nerves **tranverse the cavernous sinus & pass through the superior orbital fissure to reach orbit?
* oculomotor nerve CNIII * Trochlear nerve CNIV * Abducens nerve CNVI
43
Describe the** course of the oculomotor nerve** | ie what does it pass through, branches? what do they supply?
* CNIII extends anteriorly and divides into superior and inferior branches which both pass through the superior orbital fissure * superior branch innervates the superior rectus and levator palpebrae * the inferioer branch supplies the medial rectus, inferior rectus and inferior oblique
44
what type of innervation does the inferior branch provide?
it provides **parasympathetic innervation **to intrinsic eye muscles (sphincter pupillae and ciliary muscles)
45
what 2 nuclei are the cell bodies of the oculomotor nerve located in?
* the **oculomotor nucleus**- midbrain * the **edinger-westphal nucleus** - midbrain
46
Describe the pathway of the trochlear nerve (CN IV)
* travels trough cavernous sinus * enters orbit through superior orbital fissure outside annulus of zinn
47
descibe the pathway of the **Abducens nerve** (CN VI)
* leaves brainstem at junction of pons and medulla * to reach the eye, it runs upwards between pons and clivus, pierces the dura mater to run between dura and skull * travels lateral to carotid artery * enters orbit through superior orbital fissure within the znnulus of zinn
48
what makes the abducens nerve prone to injury?
the long course
49
what clinical issues are associated with the oculomotor nerve?
* affected eye is displaced laterally by the lateral rectus and inferiorly by the superior oblique muscle * eye adopts a down and out position
50
what are clinical issues associated with the trochlear nerve?
* paralysis of the superior oblique muscle * patient will complain of diplopia - double vision
51
what clinical issues are associated with the **abducens nerve**?
paralysis of lateral rectus muscle * the affected eye will be adducted by the resting tone of medial rectus

ANATOMY - head, neck & spine (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions