The orbit Flashcards
what are the 7 bones that make up the bony orbit
sphenoid ethmoid lacrimal frontal maxilla zyomatic palatine
What are the 5 layers of the eyelid
skin loose CT muscular layer tarsofacial layer conjunctiva
action of orbicularis oculi
oculi part is forceful closing
palpebrral-blinking
what is orbicularis oculi innervated by
facial nerve VII
damage to the orbicularis oculi is associated with
inability to blink, dry eye, pain in eye
action of levator palpebrae superioris
raises the eyelid
what is levator palebrae superioris innervated by
oculomotor nerve III
loss of function of the superior tarsal or levator palpebrae superiosis
ptosis of the upper eyelid
function of the tarsal gland
functions to increase the viscosity of the tears and decreases the rate of evaporation of tears from the surface of the eyeball
blockage of the tarsal gland results in
chalazion (inner surface of eyelid
blockage of the sebaceous or sweat glands associated with the hair follicles is called
stye (edge of eyelid)
loss of innervation of the orbicularis oculi results in what and what nerve is injured
facial nerve; inability to close eyelids tightly and lower eyelid droops
loss of innervation of the levator palpebrae superioris by the oculomotor nerve results in
complete ptosis
loss of innervation of the superior tarsal muscle by sympathetic fibers results in
partial ptosis
what are the three features of horner’s syndrome
pupillary constriction
partial ptosis
absence of sweating on the same side of the face and neck due to absence of innervation to the sweat glands
direction of fluid within the eye as you blink
lateral to medial
_______________is the opening through which fluid enters each canliculus
lacrimal punctum
sensory innervation of the lacrimal gland is via
opthalmic V1
parasympathetic innervation of lacrima gland
facial + greater petrosal= nerve to pterygoid canal PPG joines maxillary travels with zygomatic nerve branches lacrimal nerve
sympathetic innervation to lacrimal gland
same but don’t synapse in PPG lacrimal nerve
what is the periosteum that lines the bones of the orbi
periorbita
superior rectus action
elevation ,addduction and internal rotation of eyeball
inferior rectus action
depression, adduction, external rotation of eyeball
medial rectus action
adduction of eyeball
lateral rectus action
abduction of eyeball
innervation of superior rectus, inferior rectus medial rectus and inferior oblique
oculomotor III
lateral rectus innervated by
abducent nerve
superior oblque innervated by
trochlear nerve
superior oblique action
down and out
inferior oblique action
up and out
how do you clinically test superior rectus
look laterally and upward
how do you clinically test inferior rectus
look laterally and down
how do you clinically test lateral rectus
look laterally
how do you clinically test medial rectus
look medially
how do you test inferior oblique
look medially and upward
how do you test superior oblique
look medially and downward
what artery supplies the orbit
opthalmic artery
3 sources of venous drainage to the orbit
cavernous sinus, pterygoid plexus and angular vein
opthalmic V1 exist MCF via
SOF
What are the branches off opthalmic nerve
N- nasociliary
F-frontal (supratrochlear and supraorbital)
L- lacrimal
branches of nasociliary nerve
communicating branch long ciliary posterhroi ethmoidal anterior ethmooidal infratrochelar
superior division of oculomotor nerve innervates
superior rectus and levator palebrae
inferior division of oculomotor innervates
inferior rectus, medial rectus, and inferior oblique
trochlear nerve innervates what eye muscle
superior oblique
abducent nerve innervates
lateral rectus
mneumonic for eye muscles
LR6, SO4, AO3
corneal reflex
opthalmic v1 afferent, VII efferent orbicularis oculi
cranial nerve __________ senses the light in the pupillary light reflex
CN II
cranial nerve _______ carriers the parasympathetics that constrict the pupil
CN III
what is the outside of layer of the eyeball called
fibrous layer consists of cornea and sclera
vascular layers of eyeball
choroid
nervous or inner layer of the eyeball
retina
vascular layer of the eyeball includes
choroid, ciliary body, and the iris
what artery can you see with an otoscope
central retinal artery
what is the optic disk
blind spon in the eye (yellow)
