Flashcards in Basic Ophthalmology Anatomy Deck (39)
what are the 7 bones of the orbit?
what are the important entrance/exit points in the bony anatomy of the orbit?
superior orbital fissure
inferior orbital fissure
what passes through the supraorbital foramen/notch?
supraorbital nerve and vessels
what passes through the infraorbital foramen?
infraorbital nerve and vessels
what passes through the superior orbital fissure?
CN IV (trochlear - superior oblique)
CN 6 (abducens - lateral rectus)
what passes through the optic canal?
where is the optic canal found?
on posterior wall
medial to superior orbital fissure
what is the area where the iris meets the sclera called?
how many lacrimal puncta are there and where do they lead to?
- one on upper lid - drains into superior lacrimal canal > nasolacrimal duct
- one on lower lid - drains into inferior lacrimal puncta > nasolacrimal duct
where is the lacrimal gland found?
superior and lateral to the eye (brow bone)
what are the 2 types of conjunctiva?
tarsal conjunctiva = lines inner surface of eyelid
bulbar conjunctiva = lines sclera up until the corneal limbus
what are the 2 cavities of the eye and what do they consist of?
- anterior chamber = between cornea and iris
- posterior chamber = between iris and lens
- contains vitreous chamber
what are the 3 groups of extraocular muscles?
levator palpebrae superioris
what are the 3 intraocular muscles?
where is the trochlea found?
superior nasal aspect of the frontal bone within the orbit
on which side of the eye does the inferior rectus attach?
2 main actions of the superior oblique?
how can this be tested?
moves eye ball down and in which leads to looking down and out
intorsion when looking straight ahead
tested by making patient look down and in
3 main actions of inferior oblique?
how is the action of inferior oblique tested?
make patient look up and in
why does testing of the oblique muscles not match their function?
as their elevation/depression functions are strongest on adduction
the ciliary muscles are part of what?
part of ciliary body
what do the ciliary muscles do?
act as part of accommodation reflex
contraction causes relaxation of suspensory ligaments and allows lens to thicken allowing focus to shift to close up objects
what do the sphincter pupillae muscles do?
also activate in accommodation reflex as well as the light reflex to constrict the pupil
what do the dilator pupillae muscles do?
increase diameter of the pupil
are the intraocular muscles under sympathetic or parasympathetic control?
ciliary and sphincter pupillae muscles = parasympathetic
dilator pupillae = sympathetic
what nerve is responsible for special sensory (vision) in the eye?
CN 2 (optic)
sensory innervation of the eye?
motor innervation of the eye?
CN IV (trochlear = superior rectus)
CN VI (abducens = lateral rectus)
how is the autonomic nervous system involved in the eye?
sympathetic fibres from internal carotid plexus
parasympathetic fibres from edinger westphal nucleus, carried in CN III to ciliary ganglion