The orbit

Question 1

What are the bones that the orbit is made of? 7 bones

Answer 1

• frontal
• sphenoid: small and large wings
• lacrimal
• ethmoid
• maxilla
• zygomatic
• palatine

Question 2

What are the 4 walls of the orbit?

Answer 2

Superior or roof of the orbit
inferior orbit or floor
Internal
External

Question 3

The roof wall?

Answer 3

• Lesser wing of the sphenoid bone
• Frontal bone

Question 4

What are the anatomical features in the roof wall?

Answer 4

• Lacrimal gland fossa
• trochlear fovae

Question 5

How thick is the roof?

Answer 5

1 mm

Question 6

The outer wall?

Answer 6

• The frontal
• the zygomatic
• the graeter wing

Question 7

which wall is the thickest and strongest?

Answer 7

the outer wall

Question 8

Anatomical features near the outer wall?

Answer 8

• Whitnall’s tubercle: attachment to the external palpebral ligament

Question 9

The floor?

Answer 9

• the orbital process of the palatine bone
• the zygoma
• the pyramidal process of the maxilla

Question 10

How thick is the floor?

Answer 10

0.5 mm

Question 11

which floor is the fragile one?

Answer 11

The floor

Question 12

The inner wall?

Answer 12

• the lacrimal bone
• frontal
• lateral surface of the sphenoid bone
• Ethmoid

Question 13

What is the special feature of the lacrimal bone

Answer 13

• The posterior lacrimal crest:
  anterior part: lacrimal sac
  posterior part

Question 14

What is the structure that is attached to the anterior lacrimal crest?

Answer 14

• the internal palpebral ligament

Question 15

What are the part of orbital rim? - base

Answer 15

• The upper
• The lower
• the outer
• The inner

Question 16

The upper orbital rim?

Answer 16

• Frontal

Question 17

The outer orbital rim?

Answer 17

• Frontal
• zygomatic

Question 18

The lower OR?

Answer 18

• The zygoma
• The maxilla

Question 19

The inner orbital rim?

Answer 19

• Frontal
• maxilla

Question 20

The orbital apex formed by?

Answer 20

the rectangular orbital surface of the sphenoid body
corresponds to the internal end of the superior orbital fissure

Question 21

Where the optic canal is located?

Answer 21

• the small wing

Question 22

The optic canal gives away to?

Answer 22

• the optic nerve and ophthalmic artery

Question 23

Where the ZINN tendon is inserted?

Answer 23

• the suboptic tubercle: Between the optic hole and the wide part of the superior fissure

Question 24

Where The superior orbital fissure is located?

Answer 24

• Between the Greater and lesser wing

Question 25

What is the relation between ZINN ring and SOF

Answer 25

SOF is divided by the common tendinous ring

Question 26

What passes by the SOF

Answer 26

- Inside the ZINN ring: - nasal nerve - occulumotor nerve - Abducens nerve - Outside the ZINN: - trochlear nerve - Frontal nerve - Lacrimal nerve

Question 27

What is the role of Inferior orbital fissure?

Answer 27

- connects the orbit with the pterygo-palatine fossa.

Question 28

What is the role of Anterior and posterior ethmoidal holes?

Answer 28

Ethmoidal arteries and nerves ( Anterior and posterior)

Question 29

The vascularization of the Orbit

Answer 29

- Ophtalmic artery +++: ICA - Infra-Orbital artery: ECA

Question 30

The venous return of the orbit?

Answer 30

Ophtalmic veins

Question 31

What are the three segments of Ophthalmic artery?

Answer 31

- Intracranial - Intracanalicular - Intraorbital

Question 32

The origin of ophthalmic artery?

Answer 32

- Anteromedial part of the internal carotid artery. - Above the anterior clinoid process

Question 33

The relation between the ophthalmic artery and the ophthalmic nerve?

Answer 33

- Intracranial: the artery connects with the underside of the optic nerve (separated by the dura mater). - Intraductal: the artery travels below the optic nerve - Intraorbital: - Lateral optic : The artery at the lower part of the nerve - Optic part: the artery crosses the optic nerve - Medio-Optic: the artery is medial to the nerve.

Question 34

What is the length of Intracranial segment?

Answer 34

3-15 mm

Question 35

Where the orbital artery terminates?

Answer 35

the superior-internal angle of the orbit

Question 36

What are the two groupes of Collateral branches of ophthalmic artery?

Answer 36

- Optic arteries - Destinated to the appendages

Question 37

What are the optic arteries?

Answer 37

- Central retinal arteries - Short and long ciliary arteries - Optic nerve arteries

Question 38

What are the branches Destinated to the appendages?

Answer 38

- Supraorbital arteries - Ethmoidal - Lacrimal - palpebral - muscular

Question 39

What are the two groups of the otic nerve arteries?

Answer 39

- From intracanal segment - From Intraorbital segment

Question 40

What is supplied by the Supraorbital artery?

Answer 40

- the levator muscles of the upper eyelid

Question 41

What are the two groupes of the ethmoidal arteries

Answer 41

Psterior and Anterior

Question 42

What are the two groupe of Palpebral arteries- For Eyelides

Answer 42

Inferior and superior < palpebral arches.

Question 43

Termial branches of The OA?

Answer 43

- Angular artery: Anastomosis in the nose - Frontal arteries

Question 43

What about the External carotid system?

Answer 43

- Infraorbital artery - Meningeolacrimal artery: middle menengeal artery

Question 44

What is the area suppliest by the infraorbital artery?

Answer 44

around the upper orifice of the nasolacrimal duct

Question 45

The venous vascularization of the Orbit

Answer 45

- The superior ophthalmic vein - Middle ;; - Inferior

Question 46

What the 2 roots of the superior OV?

Answer 46

- Superior: frontal veins - Inferior: angular veins

Question 47

from where The middle OV comes?

Answer 47

- muscular artery: medial , lateral, Inferior recti

Question 48

From where The Inferior OV comes?

Answer 48

- muscular arteries: superior oblique, lateral and inferior recti