Orbit Flashcards
From anterior to posterior of eyeball
Cornea, Iris=pupil, lens, retina, optic n.
two comparatively thick, elongated plates of dense connective tissue, about 2.5 cm (1.0 in) in length; one is found in each eyelid, and contributes to its form and support.
Tarsal Plate
Orbital Septum
The orbital septum is a membranous sheet that acts as the anterior boundary of the orbit. It extends from the orbital rims to the eyelids. It forms the fibrous portion of the eyelids
does dos the nasolacrimal duct lead?
inferior meatus of nasal cavity
Oculomotor paralysis
lateral rectus and superior oblique still work so eyes are looking down and to the side
Tarsal Plate
are two comparatively thick, elongated plates of dense connective tissue, about 2.5 cm (1.0 in) in length; one is found in each eyelid, and contributes to its form and support.
Conjunctiva
mucous membane that covers the eyelids and is reflected onto the eyeball
Sclera
outer fascia of eye that is continuous with dura mater of optic n.
a membranous sheet that acts as the anterior boundary of the orbit.
Orbital Septum
Lines of reflection of palpebral conjunctiva onto the eyeball form deep recesses called _______
fornices
Position of lacrimal gland in orbit
Superior, anterior, lateral
Inferior rectus actions
away depression, adducts and extorsion
Lacrimal caruncle
located just lateral of lacrimal lack, involved in tear collection
What is in the optic cavity?
nerves arteries fat (to push out eye and keep it in place)
Superior rectus actions
always elevates but also adducts and intorts the eye
Lacrimal Canaliculis
Commence at a lacrimal punctum on the lacrimal papilla, near medial angle of eye and drain lacrimal fluid into lacrimal lake.
Abducens lesion
lateral rectus is not opposing the contraction of the medial rectus
outer fascia of eye that is continuous with dura mater of optic n.
sclera
what runs in the tendinous ring?
Optic N. Ophthalmic a
what drains into the nasolacrimal sac
lacrimal canaliculus
Human vs. chimps orbits
Chimps are squatting with their eyes oriented forward, but if they are standing their eyes are facing upward. Human orbits have shifted inferiorly so we are looking straight while we are upright
triangular space at medial angle of eye where tears collect
Lacrimal lake
What nerves run with the superior ophthalmic vein?
V-Frontal, IV, V lacrimal
Lacrimal gland
secretes lacrimal fluid that moistens and lubricates surface of conjunctiva and cornea, provides nutrients and dissolved O2. when produced in excess, makes tears
Lateral to lacrimal lakes, tear collection
lacrimal caruncle
What nerves are in the orbit?
V (frontal and lacrimal, nasociliary) IV - trochlear III (Superior and inferior ramus of oculomotor) VI- abducens,
Ducts of lacrima gland
lots of small little ducts that drain into the superior phronyx - the lining of the lid that is reflected onto the conjuctiva of the eye.
Lacus lacrimalis
triangular space at medial angle of eye where tears collect
junction of superior and inferior eyelids
palpebral commisures
Superior oblique actions
abduction, depression, intorsion
Inferior oblique actions
abduction, elevation, extorsion
Medial palpebral lig
connects tarsi to the medial margin of orbit orbicularis oculi inserts into this ligament
Lacrimal lake
are blinking, tears are swept across the cornea to gather here where they drain into the lacrimal canaliculus
Fornices in the orbit
Lines of reflection of palpebral conjunctiva onto the eyeball form deep recesses Superior and lateral
what muscles in the eye are normally contracted for steroscopic vision?
Medial rectus adducts the eye from its natural position to move the visual field more forward.
