Session 8 - The Eye

Question 1

What three openings are found at the apex of the orbital cavity?

Answer 1

Superior orbital fissure
Inferior orbital fissure
Optic canal

Question 2

What are the bones forming the walls of the orbit?

Answer 2

Floor:

• maxilla
• zygomatic

Medial wall:

• maxilla
• lacrimal
• ethmoid
• sphenoid

Roof:

• frontal
• sphenoid

Lateral wall:

• zygomatic
• sphenoid

Question 3

Which walls of the orbit are the most vulnerable to fracture?

Answer 3

Medial wall and floor - thinnest.

Most common wall to fracture is the floor.

Question 4

How might a fracture of the floor of the orbit occur?

Answer 4

Direct impact to the front of the eye (e.g. by a ball or fit) causing an orbital blow-out fracture due to sudden increase in orbital pressure.

Question 5

How will and orbital blow-out fracture present?

Answer 5

History of trauma to eye/orbit
Periorbital swelling, painful
Double vision (especially on vertical gaze)
Impaired vision
Anaesthesia over affected cheek (upper teeth and gums) on affected side

Question 6

In an orbital blow out fracture, blood and orbital contents can prolapse into which sinus?

Answer 6

Maxillary sinus

Question 7

What are the contents of the orbital cavity?

Answer 7

Globe of the eye (eyeball)
Extra-ocular muscles
Lacrimal apparatus 
Nerves and blood vessels 
Orbital fat

Question 8

What is another name for eyelids?

Answer 8

Palpebrae