eye Flashcards
the protective layer of the globe consists of the
sclera and the cornea
where the sclera meets the cornea is the
limbus
the middle nourishing layer of the globe is the
uvea
the three parts of the uveal tract are
iris ciliary body and choroid
the uvea contains pigment called
melanin
the _ is the most anterior part of the uvea that is the moving diaphragm of the eye
iris
the _ lies between the iris and choroid containing the ciliary muscle and ciliary process
ciliary body
The _ controls our ability to accommodate change our focus from near to distance
ciliary muscle
The _ produces aqueous humor
ciliary processes
_ is a watery clear fluid that fills the anterior chamber maintaining intraocular pressure
aqueous humor
_ is the clear jelly-like substance in the posterior chamber supporting the eye
vitereous
the _ is a biconvex transparent structure sitting behind the pupil that refracts light
crystalline
the inner most nervous receptor layer of the globe is the
retina
the retina contains visual receptors called _ which take light energy and convert it into nerve impulses that are transmitted by neurons through the optic nerve fibers to the center in the brain for perception
rods and cones
_ is the connective tissue surrounding the globe and extraocular muscle, allowing the eye to move freely and not get hung up on the fat surrounding it.
tenon’s capsule
the normal anterior-posterior diameter of the eye is
24mm
the _ includes the orbit, extraocular muscles eyelids and tear-producing and tear-draining lacrimal apparatus
adnexa
the _ is the bony cavity in the skull where the globe, extraocular muscles, blood vessels, and nerve sit
orbit
the orbit is surrounded by the
sinuses
the main bones in the orbital roof are the_ bones and the _ bone where the optic canal ( and nerve) pass through
frontal, lesser wing of sphenoid
the _ is found in a groove towards the lateral front of the roof
lacrimal gland
the main bones of the orbital lateral wall are the _ bone, and the _ (malor) bone
greater wing of sphenoid, zygumatic
The _ bone is the strongest part of the bony orbit
zygomatic
the main bone in the orbital floor is the __ bone where blow out fractures usually occur. The floor also includes the _ bone
maxilla, palatine
the main medial wall orbital bones are the__ bone which is paper thin and the _ bone
ethmoid, lacrimal
The _ is a thin sheet of fibrous membrane that goes from the orbital rim to the tarsus in both lids that prevents the spread of infection and holds back orbital fat behind it
orbital septum
the optic nerve, ophthalmic artery, and sympathetic nerves enter the orbit through the
optic foramen
the _ branches from the internal carotid artery in the neck and enters the optic nerve becoming the central retinal artery. It also branches to the lacrimal gland, posterior ciliary arteries, eyelids, and extraocular muscles.
ophthalmic artery
the _ leaves the optic nerve behind the artery and joins the superior ophthalmic vein that exits through the superior orbital fissure
central retinal vein
the superior ophthalmic vein drains into the _ which is a large vein that sits behind the superior orbital fissure
cavernous sinus
the _ are divided into two upper and two lower veins in each quadrant of the eye and drain the choroid, lacrimal and EOM veins.
vortex veins
the _ of the orbit is the entry for all nerves and vessels to the eye and origin of most of the extraocular muscles
apex
the origin of the extraocular muscles except the inferior oblique, is also called
annulus of zin
the cranial nerves enter the eye through the _ after passing through the cavernous sinus
superior orbital fissure
three nerves travel outside the annulus of Zinn and are the
lacrimal, frontal, and trochlear nerves
the three nerves that travel within the annulus of Zinn are the
oculamoter, abducens, nasociliary nerves
the 1st division of the trigeminal nerve divides into _ nerve for tears, the _ nerve for brow and forehead sensation, and the _ nerve for the near reaction ( accommodation, convergence, and constriction of the pupil) and branches to the cornea and near tip of the nose.
lacrimal, frontal, nasociliary
the 2nd ( maxillary) division of the trigeminal nerve supplies sensation to the lower lid and cheek and can be damaged in __ also known as __
fractures of the orbital floor, blow out fractures
the 2nd division of the trigeminal nerve enters the orbit through the _ that tunnels forward to the __ in the maxillary bone
inferior orbital fissure, inferior orbtial foreman
it is thought that the inferior ophthalmic vein leaves the orbit through the inferior orbital fissure and drains
below the orbital floor
the _ nerve is the longest nerve and innervates the superior oblique muscle
trochlear
the _ nerve innervates the levator muscle, inferior oblique, superior- medial- and inferior rectus muscles, and ciliary ganglion for the near response also
oculormotor
the _ nerve innervates the lateral rectus muscle
abaucens
tool to remember nerve to extraocular muscle innervation
LR6 sO4, rest 3
