Parker SG (Orbit)

Question 1

What bones make up the roof of the orbit?

Answer 1

1. Orbital Plate of Frontal Bone

2. LESSER wing of sphenoid

Question 2

What bones make up the lateral wall of the orbit?

Answer 2

1. Zygomatic

2. GREATER wing of sphenoid

Question 3

What bones contribute to the medial wall of the orbit?

Answer 3

1. Frontal
2. Ethmoid
3. Lacrimal
4. BODY of sphenoid
   (pre-study guide adds palatine)

Question 4

What bone makes up the floor of the orbit?

Answer 4

1. Maxilla

pre-study guide adds palatine

Question 5

What 5 muscles are innervated by oculomotor n. (CN III)?

Answer 5

Upper:

1. Superior Rectus
2. Levator Palpebrae Superioris

Lower:

3. Medial Rectus
4. Inferior Rectus
5. Inferior Oblique

Question 6

What do the 4 rectus mm. originate from?

Answer 6

• Common Tendinous Ring

Question 7

What 3 mm. aDduct the eye?

Answer 7

• Superior, Inferior, Medial Rectus

Question 8

What 3 mm. aBduct the eye?

Answer 8

• Superior, Inferior Oblique

- Lateral Rectus

Question 9

What 2 mm. elevate the eye?

Answer 9

Superior Rectus, Inferior Oblique

Question 10

What 2 mm. depress the eye?

Answer 10

Inferior Rectus, Superior Oblique

Question 11

SO4LR6

Answer 11

Superior Orbital (IV)
Lateral Rectus (VI)

Question 12

What nerve passing through the supraorbital fissure contains GSA fibers?

Answer 12

Opthalmic n. (V1)

Question 13

What are the 3 branches of opthalmic n. (V1) in the orbit?

Answer 13

1. Frontal n. (V1)
2. Lacrimal n. (V1)
3. Nasociliary (V1)

Question 14

What artery runs with the nasociliary n. (V1)?

Answer 14

Opthalmic a.

Question 15

What neurovascular structures cross the Optic n. (CN II)?

Answer 15

1. Opthalmic a. (traveling with…)

2. Nasociliary n. (V1)

Question 16

What 5 branches of the nasociliary n.?

Answer 16

1. Anterior Ethmoid n.
2. Posterior Ethmoid n.
3. LONG ciliary nn.
4. Sensory Root to Ciliary Ganglion
5. Infratrochlear n.

Question 17

What hitchhiker travels with the lacrimal n.?

• Ganglia
• Preganglionic
• Postganglionics

Answer 17

Preganglionic:
Greater Petrosal n. (CN VII) –> Nerve of Pterygoid Canal –> PTERGOPALATINE GANGLIA

Postgangionic HITCHHIKERS:
Infraorbital n. —> Zygomatic n. –> Lacrimal n. (via communicating branch)

Question 18

What are the parasympathetic preganglionic to the orbit?

- associated ganglia

Answer 18

CN III - Oculomotor
CN VII - (greater pet.)

ganglia:

• Ciliary
• PPG

Question 19

What are the parasympathetic preganglionics to the PP Fossa?

- associated ganglia

Answer 19

CN VII - (greater pet.)

ganglia:
- PPG

Question 20

What are the parasympathetic pregangionics to the IT Fossa?

- associated ganglia

Answer 20

CN VII - (Chorda Tympani)
CN IX - Lesser Pet.

ganglia:

• PPG
• Otic

Question 21

What 3 fiber types are received by the ciliary ganglion?

- How do they get there?

Answer 21

Sympathetic Root:
Postganglionic Sympathetics - via opthalmic a.

GSA Root:
- Nasociliary n. via its sensory root

Parasympathetic Root:
- Pregalionic GVE fiber from CN III parasympathetic motor root

Question 22

What two structures are linked by the short ciliary fibers?

- fiber type

Answer 22

• Ciliary ganglion to Globe

**???

Question 23

What two structures are linked by the Long Ciliary Fibers?

Answer 23

• Nasociliary n. to Globe

**Direct GSA branches

Question 24

What fiber type dilates the pupil?

Answer 24

Sympathetics

Question 25

What fiber type constricts the pupil and accomadates the pupil?

Answer 25

Parasympathetics

Question 26

What structures travel through the superior orbital fissure?

Answer 26

1. Oculomotor (CN III) 2. Trochlear (CN IV) 3. Opthalmic n. (CN V1) 4. Abducens n. (CN VI) 5. Superior and Inferior Opthalmic vv.

Question 27

How does the optic n. (CN II) enter the orbit? | - what comes with it?

Answer 27

- Through the Optic Canal | - Opthalmic a. travels with Optic n.

Question 28

What 4 neurovascular structures enter the optic canal above the tendinous ring?

Answer 28

1. Frontal n. (V1) => Opthalmic (V1) 2. Lacrimal n. (V1) => Opthalmic (V1) 3. Troclear n. (IV) 4. Superior Opthalmic v.

Question 29

What 6 neurovascular structures enter the optic canal INSIDE the tendinous ring?

Answer 29

1. Optic n. (CN II) 2. Opthalmic a. => INTERNAL carotid 3. Abducens n. (CN VI) 4. Upper Division CN III 5. Lower Division CN III 6. Nasociliary n. => Opthalmic (CN V1)

Question 30

What 1 thing enters the orbit below the tendinous ring?

Answer 30

1. Inferior Opthalmic a.

Question 31

What is anything tagged in the floor of the sphenoid sinus going to be?

Answer 31

N. or A. of the Pterygoid Canal

Question 32

T or F: the opthalmic a. is a branch of the external carotid a.

Answer 32

False, it comes from the INTERNAL carotid

Question 33

What vascular structure can cause bulging of the eyes?

Answer 33

Infections in the cavernous sinus preventing flow from opthalmic veins putting pressure on the eyes