Orbit Flashcards
what bone contains the optic foramen
lesser wing of sphenoid
what bone contains the inferior orbital fissure and superior orbital fissure
sphenoid
what bones make up the orbit
frontal, ethmoid, lacrimal, maxilla, zygoma, sphenoid
what is the tendinous ring
structure which gives rise to the 4 rectus muscles
what artery runs alongside the optic nerve
opthalmic
what is the function of retrobulbar fat
fills the orbit and supports the eyeball
what vascular structures run through the optic nerve
central retinal artery and vein
what is Amaurosis fugax
painless transient monocular or binocular visual loss
may be caused by a thrombus of the central artery of the retina
what is the cause of papilloedema
raised intracranial pressure slows retinal venous drainage via the central retinal vein causing oedema
where is the lacrimal gland
upper lateral corner of the orbit
tears are washed into the conjunctival sac
what muscle is needed in order to keep the cornea and conjunctivae moist
obicularis oculi via cn 7
what muscle is responsible for blinking
palpebral part of obicularis oculi
what muscle closes the eye tightly
orbital part of obicularis oculi
what is the name of the pink thing at the medial corner of the eye
lacrimal caruncle
how do tears drain
via punctae to canaliculi, to lacrimal sacs, to nasolacrimal duct and to inferior meatus
what is Levator Palpebrae Superioris
the muscle that elevates the upper eyelid
where do stys form
ciliary sebaceous glands of the eyelashes
what structure in the eyelid lubricates the lids
tarsal plate and tarsal glands (cysts can form)
where is the central retinal artery and vein
runs through the optic nerve
what structures surround the optic nerve
meninges
what can result from malfunction of ob oculi
dry eye, leakage of tears, sagging of the lower lid
corneal ulceration
where can cysts form in the eye
tarsal plate in the eyelid
what is the hay fever ganglion
pterygopalatine (involved in the lacrimal gland)
what is the opthalmic artery a branch of
internal carotid
what is muscle action dependent on
direction of gaze and action of other muscles
what is the function of superior oblique
pull the eye downwards and laterally
what is the function of inferior oblique
pulls the eye superiorly and laterally
what are the 3 axes that they eye can move around
transverse
AP
vertical
when would you get diplopia when looking right
injury to the right abducens nerve
what muscles are involved in looking straight down
superior oblique and inferior rectus
what muscles can elevate the eye when looking laterally
superior rectus
obliques do not work when looking laterally
what muscles elevate and depress the eye when looking medially
obliques
sup and inf rectus do not work
what is the function of the H shape testing
isolates obliques and sup and lat rectus muscles
eye is turned down and out
dilated pupil
ptosis
occulomotor injury
what does the opthalmic artery supply
forehead, eye and part of nasal cavity
why might eye infection spread to the cavernous sinus
orbital veins anastomose with forehead veins which drain to the cavernous sinus
describe the consensual light reflex
in the tectum, nerve fibres cross the midline to stimulate the opposite EW nucleus
