The bony orbit (eye)

Question 1

what are the bony orbits?

Answer 1

(eye sockets) are bilateral and symmetrical cavities in the head

Question 2

what do the bony orbits enclose?

Answer 2

the eyeball and its associated structures

Question 3

how can the orbit be thought of?

Answer 3

as a pyramidal structure, with the apex pointing posteriorly and the base situated anteriorly

Question 4

what forms the boundaries of the orbit?

Answer 4

seven bones

Question 5

what are the 7 bones forming the bony orbit?

Answer 5

frontal
sphenoid
lacrimal
ethmoid
maxilla
zygomatic

Question 6

what forms the roof (superior wall) of the bony orbit?

Answer 6

frontal bone and the lesser wing of the sphenoid

Question 7

what does the frontal bone do?

Answer 7

separates the orbit from the anterior cranial fossa

Question 8

what forms the floor (inferior wall) of the bony orbit?

Answer 8

Formed by the maxilla, palatine and zygomatic bones

Question 9

what does the maxilla separate?

Answer 9

separates the orbit from the underlying maxillary sinus

Question 10

what forms the medial wall of the bony orbit?

Answer 10

Formed by the ethmoid, maxilla, lacrimal and sphenoid bones

Question 11

what does the ethmoid bone separate?

Answer 11

separates the orbit from the ethmoid sinus

Question 12

what forms the lateral wall of the bony orbit?

Answer 12

Formed by the zygomatic bone and greater wing of the sphenoid

Question 13

where is the apex of the bony orbit located?

Answer 13

at the opening to the optic canal, the optic foramen

Question 14

what does the base of the bony orbit open out into?

Answer 14

Opens out into the face

Question 15

what bounds the base of the bony orbit?

Answer 15

bounded by the eyelids

Question 16

what is the base of the bony orbit also known as?

Answer 16

orbital rim

Question 17

contents of the bony orbit?

Answer 17

contains the eyeballs and their associated structures

Question 18

associated structures within the bony orbit?

Answer 18

Extra-ocular muscles
Eyelids
Nerves
Blood vessels

Question 19

function of extra-ocular muscles?

Answer 19

These muscles are separate from the eye. They are responsible for the movement of the eyeball and superior eyelid

Question 20

what do eyelids cover?

Answer 20

These cover the orbits anteriorly

Question 21

nerves within the bony orbit?

Answer 21

Several cranial nerves supply the eye and its structures; optic (II), oculomotor (III), trochlear (IV), trigeminal (V) and abducens (VI) nerves (2-6)

Question 22

venous drainage within the bony orbit (draining the eye)?

Answer 22

superior and inferior ophthalmic veins

Question 23

artery within the bony orbit? (supplying the eye)

Answer 23

ophthalmic artery

Question 24

Any space within the orbit that is not occupied is filled with what?

Answer 24

orbital fat

Question 25

what is the function of orbital fat?

Answer 25

This tissue cushions the eye, and stabilises the extraocular muscles