week 3 anatomy Flashcards
how long is the bony orbit?
8cm
what part of the sphenoid bone forms part of the bony orbit?
wings
what are 4 structures of note in the bony orbit?
optic foramen
superior orbital fissure
inferior orbital fissure
infra orbital groove
where does the optic nerve pass through?
optic nerve
where does the opthalmic artery pass through?
opthalmic artery
what passes through the superior orbital fissure?
branches of opthalmic and
motor nerves to the eye (III IV VI)
what passes through the inferior orbital fissure?
maxillary division of cranial nerve V
what cranial nerves innervate the muscles of the eye?
III
IV
VI
how many muscles move the eyeball?
6
what forms the fibrous coat of the eyeball?
cornea
sclera
what forms the vascular coat of the eyeball?
iris
ciliary body
choroid
what forms the sensory coat of the eyeball?
retina
where is the aqueous humor located?
lens
what is the choroid rich in?
vasculature
what does the ciliary body do?
suspends the lens and produces aqueous humour
what is the function of the iris?
controls diameter of pupil
what is the function of the choroid?
supplies blood to outer layers of retina
what is the function of the retina?
contains light sensitive rods and cones which enable vision
what is the vitrous humor?
transparent gel posterior to the lens.
what is the function of the intrinsic ocular muscles?
control pupil diameter and helps alter lens curvature to enable us to see near objects
what is the function of the extrinsic ocular muscles?
move the eye
what are the intrinsic ocular muscles?
ciliaris muscle
constrictor pupillae
dilator pupillae
what branch of the autonomic nervous system innervates the intrinsic eye muscles?
ciliaris - parasympathetic
constrictor pupillae - parasympathetic
dilator pupillae - sympathetic
what are the 2 types of muscles in the extrinsic ocular muscles?
straight and oblique muscles?
what are the 6 extrinsic ocular muscles?
medial rectus (S) lateral rectus (S) inferior rectus (S) superior rectus (S) superior oblique (O) inferior oblique (O)
what innervates the superior oblique
cranial nerve IV
what innervates the lateral rectus?
cranial nerve VI
what innervates every extrinsic ocular muscle apart from the medial and lateral rectus muscles?
cranial nerve III
where does the lacrimal gland lie?
laterally in the orbit
what innervates the lacrimal gland?
facial nerve
where do the lacrimal ducts open into?
the conjunctival sac
where does the lacrimal sac drain into?
inferior meatus of nasal cavity
what muscles are contained in the middle ear
tensor tympani
stapedius
what part of the temporal bone do the middle and inner ear lie in?
petrous part
what foramen do cranial nerves VII and VIII pas through?
internal acoustic foramen