EYE (E3) Flashcards
Define adnexa
The group of structures surrounding the eyeball which provide protection and movement
What portion of tear film do the tarsal glands produce?
the oily portion
What portion of the tear film do the gland of the 3rd eyelid and the lacrimal gland produce?
the aqueous portion
What is another name for the 3rd eyelid?
plica semilunaris
What is the orbit?
the cavity containing the eyeball
What is the periorbita?
a cone-shaped sheath of CT and smooth m that encloses the eyeball and its muscles, vessels and nerves
outermost layer of the eyeball?
cornea
How do you recognize the sclera?
the white of the eye
what is the choroid?
the pigmented posterior portion of the vascular coat of the eyeball
What is the fundus?
the posterior portion of the eyeball
What is the fluid posterior to the lens?
jelly-like vitreous body
What is the fluid anterior to the lens?
aqueous humor
What is the retina?
part of the internal coat of the eyeball. contains rods and cones
palpebral fissure
the opening between the 2 eyelids
medial and lateral palpebral commissures
where the uper and lower eyelids join (medial and lateral)
palpebral conjunctiva
mucosal membranes that line the inner eyelids
bulbar conjunctiva
mucosal membranes that covers the sclera
conjunctival sac
bound externally by palpebral conjunctiva and interally by bulbar conjunctiva. opens at the palpebral fissure
lacrimal gland
on dorsolateral border of eyeball, medial to orbital ligament; makes tears
levator palpebrae superioris muscle
innervated by the oculomotor nerve (III); begins at the apex of the orbit, over the dorsal rectus; thin muscle that controls the movement of the eyelid
dorsal rectus muscle
innervated by the oculomotor nerve (III); attaches dorsally to eyeball
medial rectus muscle
innervated by the oculomotor nerve (III); attaches medially to eyeball
ventral rectus muscle
innervated by the oculomotor nerve (III); attaches ventrally to eyeball
retractor bulbi muscle
innervated by the abducens nerve (VI); surrounds the optic nerve with its four fascicles; when contracted, third eyelid is able to cover eyeball
lateral rectus muscle
innervated by the abducens nerve (VI); attaches laterally to eyeball
dorsal oblique muscle
innervated by the trochlear nerve (IV); passes through a groove in the trochlea (cartilaginous structure medially) and then courses laterally
ventral oblique muscle
innervated by the oculomotor nerve (III); attaches near where lateral rectus attaches and courses medially across ventral rectus
trochlea
a smooth, grooved cartilaginous process shaped like a pulley in the eye medially; dorsal oblique muscle is set within a groove
superficial gland of the third eyelid
gland attached ventrally to the third eyelid
external fibrous coat is composed of?
sclera and cornea
limbus
border between cornea and sclera
middle vascular coat (uvea) made up of?
choroid, ciliary body, and iris
iris
contains circular and radial smooth muscle; allows/restricts light from entering eyeball
choroid
middle, vascular layer of the eye; attaches firmly to the inside of the sclera
ciliary body
located between the iris and choroid; contains numerous muscle bundles that regulate the shape of the lens
ciliary processes
longitudinal tissue folds at the anterior part of the ciliary body; anchor zonular fibers
lens
a structure that focuses the light on the retina; held in place with zonular fibers between two chambers in the eye
vitreous chamber
most posterior chamber of the eye, filled with vitreous body
optic disk
blind spot; an opening in the retina where the optic nerve fibers exit the eye
1
external fibrous layer of the eye
2
middle vascular (uvea) layer of the eye
3
internal layer (retina)
A
dorsal rectus
B
medial rectus
C
Ventral rectus
D
lateral rectus
a
dorsal oblique
b
ventral oblique
action of dorsal rectus?
elevates the globe
which CN is dorsal rectus innervated by?
CN III
Action of ventral rectus?
Depresses the globe
which CN is the ventral rectus innervated by?
CN III
action of medial rectus
turns the globe medially (nasally)
which CN is the medial rectus innervated by?
CN III
action of the lateral rectus?
turns globe laterally
which CN innervates lateral rectus?
CN VI (Abducens)
action of dorsal oblique?
rotates the 12 o’clock position medially (intortion of the globe)
which CN innervates the dorsal oblique?
CN IV (Trochlear)
action of ventral oblique
rotates the 12 o’clock position laterally (extortion of the globe)
which CN innervates the ventral oblique?
CN III
action of the retractor bulbi?
retract the globe
which CN innervated the retractor bulbi?
CN VI (Abducens)
dilation of the pupil
mydriasis
constriction of the pupil
miosis
