1 - Orbital Anatomy

Question 1

Volume de l’orbite

Answer 1

30 cm^3

Question 2

Entrance height de l’orbite

Answer 2

35 mm

Question 3

Entrance width

Answer 3

40-45 mm

Question 4

Longueur du medial wall

Answer 4

40-45 mm

Answer 5

Question 6

Length of orbital segment of optic nerve?

Answer 6

25-30 mm

Question 7

Pourquoi le NO a-t-il une S-shaped curve dans le segment intraorbitaire?

Answer 7

The intraorbital segment of the optic nerve has an S- shaped curve, allowing the eye to rotate and move forward with some freedom, without placing excessive tension on the posterior globe insertion (globe tenting).

Question 8

Origine du septum orbitaire?

Answer 8

The orbital septum arises anteriorly from the orbital rim.

Selon Dr Daigle : provient/continuation du périoste

Question 9

Nommez les os de l’orbite.

Answer 9

The orbital walls are composed of 7 bones:
* Ethmoid
* Frontal
* Lacrimal
* Maxillary (maxilla)
* Palatine
* Sphenoid
* Zygomatic

Question 10

Nommez les os du roof of the Orbit

Answer 10

The roof of the orbit is composed of the orbital plate of the frontal bone and the lesser wing of the sphenoid bone.

Question 11

3 importants landmarks a/n du toit de l’orbite

Answer 11

The roof of the orbit is located adjacent to the anterior cranial fossa and frontal sinus and includes the following important landmarks :
* the fossa of the lacrimal gland, which contains the orbital lobe of the lacrimal gland
* the fossa for the trochlea of the superior oblique tendon, located 5 mm behind the superonasal orbital rim
* the supraorbital notch, or foramen, which transmits the supraorbital vessels and the supraorbital branch of the frontal nerve