Anatomy Flashcards
(47 cards)
what 2 bones are most vulnerable to a blow out fracture
orbital bone of maxilla and ethmoid
what is a trapdoor fracture
orbit bone break and contents herniates and becomes trapped
what are the muscles that close the eye
obicularis Oculi (CN VII)
what are the muscles that open the eye
superior tarsal muscle (Mueller’s muscle), inferior tarsal muscles and levator palpebral superioris
what are the muscles that open the eye innervated by
CN III
what are the 3 eye layers
fibrous- sclera and cornea
uvea- ciliary body, iris, chores
retina- macula, optic disc
the lens divides the eye into segments, the segments in front of the lens is divided into _______ and ________
anterior- contains iridocorneal angle
posterior chamber- produces aqueous humor
describe the ciliary body
has suspensory ligaments (zonules) that attach to the lens. the CB itself is a sphincter muscle.
secretes aqueous humour and supports lens (for accommodation reflex)
T/F: CN VII innervates ciliary body
F: CN III
what is the path of the acqueous humour?
secreted into posterior chamber > through pupil to anterior chamber > reabsorbed via canal of schlemm at iridocorneal angle
the ______ _______ artery becomes the ______ artery. this ______ artery itself branches into _______ artery of retina and _____ artery
internal carotid artery becomes ophthalmic artery which branches into central retinal artery (end artery) and ciliary arteries
what is the fundus and what is it made up of
where light is focussed (back of retina)
- optic disc (axons meet)
- fovea (centre of macula)
- macula (greatest no of cones)
know the cranial nerves in the brain and the foramen
look at pics
what is the lacrimal apparatus made up of
lacrimal gland, secretes lacrimal fluid which washes over eye, lacrimal lake and lacirimal puncta> nasolacrimal duct
know the visual pathway
‘what starts on the outside, stays on the outside’
what innervates the lacrimal apparatus
lacrimal gland (CN V1) PS innervation of secretion of lacrimal fluid by CN VII
what are the extraocular muscles and their innervation
lateral rectus- CN VI
inferior rectus, superior rectus, medial rectus, inferior oblique- CN III
superior oblique- CN IV
what is the pulley mechanism in place for the superior oblique extraocular muscle
trochlea
where does LPS originate and insert into
origin- lesser wing
insertion- tarsus of superior eyelid
what are 3 trigeminal branches
V1- ophthalmic division
V2- maxillary division
V3- mandibular division
what is the innervation for corneal reflex (blink)
afferent: CN V1 > CN V to pons
CNS: connection between CN V and CN VII
motor: CN VII to obicularis oculi to close eye
difference between sympathetic and parasympathetic reflexes of the eye
sympathetic: more light (pupil dilation), focus on far objects
parasympathetic: less light, less focus, reflex lacrimation
what are the 6 reflexes
- wide eye opening
- pupil light reflex
- accomodation reflex
- lacrimation reflex
- vestibule-ocular reflex
- oculocardiac reflex
which muscle lack of results in Horner’s
Mueller’s muscle
