The bony orbit (eye) Flashcards
(25 cards)
what are the bony orbits?
(eye sockets) are bilateral and symmetrical cavities in the head
what do the bony orbits enclose?
the eyeball and its associated structures
how can the orbit be thought of?
as a pyramidal structure, with the apex pointing posteriorly and the base situated anteriorly
what forms the boundaries of the orbit?
seven bones
what are the 7 bones forming the bony orbit?
frontal sphenoid lacrimal ethmoid maxilla zygomatic
what forms the roof (superior wall) of the bony orbit?
frontal bone and the lesser wing of the sphenoid
what does the frontal bone do?
separates the orbit from the anterior cranial fossa
what forms the floor (inferior wall) of the bony orbit?
Formed by the maxilla, palatine and zygomatic bones
what does the maxilla separate?
separates the orbit from the underlying maxillary sinus
what forms the medial wall of the bony orbit?
Formed by the ethmoid, maxilla, lacrimal and sphenoid bones
what does the ethmoid bone separate?
separates the orbit from the ethmoid sinus
what forms the lateral wall of the bony orbit?
Formed by the zygomatic bone and greater wing of the sphenoid
where is the apex of the bony orbit located?
at the opening to the optic canal, the optic foramen
what does the base of the bony orbit open out into?
Opens out into the face
what bounds the base of the bony orbit?
bounded by the eyelids
what is the base of the bony orbit also known as?
orbital rim
contents of the bony orbit?
contains the eyeballs and their associated structures
associated structures within the bony orbit?
Extra-ocular muscles
Eyelids
Nerves
Blood vessels
function of extra-ocular muscles?
These muscles are separate from the eye. They are responsible for the movement of the eyeball and superior eyelid
what do eyelids cover?
These cover the orbits anteriorly
nerves within the bony orbit?
Several cranial nerves supply the eye and its structures; optic (II), oculomotor (III), trochlear (IV), trigeminal (V) and abducens (VI) nerves (2-6)
venous drainage within the bony orbit (draining the eye)?
superior and inferior ophthalmic veins
artery within the bony orbit? (supplying the eye)
ophthalmic artery
Any space within the orbit that is not occupied is filled with what?
orbital fat
