Skull and Orbital Anatomy

Question 1

Try to remember these parts of the skull

Answer 1

Question 2

Remember this diagram of orbital anatomy

Answer 2

Question 3

Two bony cavities occupied by the eyes and associated muscles, nerves, blood vessels, etc.

Answer 3

Orbits

Question 4

Where are the apex and base of the orbit situated?

Answer 4

Apex - Posteriorly

Base - Anteriorly

(Shaped by a 4 sided pyramid)

Question 5

What structure is at the apex of the “bony pyramid” of the orbital

Answer 5

Optic Foramen

(think, how else do you get optical nerve through?)

Question 6

Zygomatic process of frontal bone and greater wing of the sphenoid (orbital anatomy)

Answer 6

Lateral Wall

Question 7

From anterior to posterior, this contains the

maxilla, lacrimal bone, lamina papyracea

Answer 7

Medial Wall

Question 8

Orbital surfaces of the zygomatic bone and maxilla

Answer 8

Floor

Question 9

Orbital plate of the frontal bone

Answer 9

Roof

Question 10

Posterior part of the orbital roof

Carries the optic nerve and ophthalmic artery from the middle cranial fossa

Answer 10

Optic Canal

Question 11

Structure between the greater and lesser wings of sphenoid bone

Carry CN III, IV, VI

Carries CN V₁

Answer 11

Superior Orbital Fissure

Question 12

Structure between greater sphenoid wing and the maxilla

Carries CN V₂

Answer 12

Inferior Orbital Fissure

Question 13

Gloss over these two diagrams of V₁ V₂ and V₃ nerve distribution

Answer 13

Question 14

Functions of the Lacrimal Gland

Answer 14

Produces secretions (tears) to lubricate eyes

Drains into the lacrimal duct (this is why your nose is runny when you cry)

Question 15

Where does the Lacrimal duct lie?

Answer 15

In the Lacrimal Fossa (recess of the frontal bone)

Question 16

What emerges from the internal carotid artery after the cavernous sinus

Is the only branch of the internal carotid artery

Answer 16

Opthalmic Arter

Question 17

Remember this diagram of the anatomy of the eye

Answer 17

Question 18

What part of the eye is responsible for focusing light?

Answer 18

Cornea and Lens

Question 19

What part of the eye controls how much light reaches the eye?

It also adjusts the size of the pupil

Answer 19

Iris

Question 20

What part of the eye further focuses light via accomodation?

Answer 20

Lens

Question 21

What part of the eye converts light to electronic signal?

Answer 21

Retina

Question 22

Quickly look at optical nerve pathway

Answer 22

Question 23

How many extraocular muscles are there?

What are they?

Answer 23

7 in total,

4 rectus muscles

1 Levator papebrae suprioris

1 inferior and 1 superior oblique muslces

Question 24

Which muscle of the eye is responsible for moving it TOWARDS the nose

Answer 24

Medial Rectus

Question 25

Which muscle of the eye is responsible for moving it AWAY from the nose?

Answer 25

Lateral Rectus

Question 26

Which muslces of the eye move it up and down

Answer 26

Superior rectus - up Inferior rectus - down

Question 27

Which nerve is attached to the Superior Oblique muscle Which to the Lateral Rectus?

Answer 27

CN IV to superior oblique (Trochlear) CN VI to lateral rectus (Abducens nerve) (Everything else is CN III, oculomotor)

Question 28

What are the three major orbit compartments divided by the muscle cone?

Answer 28

Intraconal Conal Extracona

Question 29

What does the Intraconal compartment hold?

Answer 29

Optic Nerves Vessels Fat

Question 30

What does the conal department hold?

Answer 30

Defined by extraocular muslces

Question 31

What does the Extraconal compartment hold?

Answer 31

Lacrimal Gland Fat Lymphoid tissue

Question 32

Which bone of the skull has complex inside to let CN VII, VIII and cochlear through?

Answer 32

Temporal Bone

Question 33

What is a hole in the ocipital bone where brain stem becomes the spinal cord?

Answer 33

Foramen Magnum

Question 34

What opening do the CN 7 and 8 go through in the temporal bone?

Answer 34

Internal Acoustic modulus

Question 35

Where does the CN V₂ go through?

Answer 35

Inferior orbital fissure after accessing through foramen rotundum

Question 36

What does the foramen rotundum innervate with?

Answer 36

Mid parts of the face

Question 37

Try to remember these visual field deficits.

Answer 37

Question 38

What suture separates the parietal bone from the frontal?

Answer 38

Coronal Suture