Orbit

Question 1

Palpebral Fissure

Answer 1

opening between eyelids

Question 2

Tarsal glands

Answer 2

located in the superior and inferior tarsus; secrete oily fluid that forms a layer over the tears to prevent them from evaporating too quickly

Question 3

Tarsal Plates

Answer 3

superior and inferior tarsus (aka upper and lower eyelids); they are linked to the skull bone by medial and lateral palpebral ligaments

Question 4

Orbital Septum

Answer 4

the rest of the connective tissue around the eyelids

Question 5

Conjunctiva

Answer 5

lines the inside of the eyelids

Question 6

Superior fornix

Answer 6

opening where the lacrimal glands will secrete its tears into

Question 7

Lens

Answer 7

is transparent, colorless, avascular, biconvex lens that is held in place by zonule fibers

Question 8

Zonule fibers

Answer 8

will pull or lack on lens thus controlling its thickness; ex: when zonule fibers are relaxed it will cause lens to thicken (accomodation) which is usually done when focusing on near objects

Question 9

Cataracts

Answer 9

clouded lens

Question 10

Anterior cavity

Answer 10

in front of lens; is filled with aqueous humor and further subdivided into anterior chamber (between cornea and iris) and posterior chamber (between iris and lens)

Question 11

Hyaloid Canal

Answer 11

Hyaloid artery used to pass through this opening as a baby but will disappear as adults

Question 12

Sclera

Answer 12

White part of the eye; it is the insertion point of the extraocular m.’s; it is also pierced by the optic nerve and ciliary arteries

Question 13

Cornea

Answer 13

transparent, avascular, and major refractive/focusing structure

Question 14

Choroid layer

Answer 14

vascular layer under the sclera that will eventually turn into the ciliary body

Question 15

Ciliary body

Answer 15

vascular muscle that controls the zonule fibers; when ciliary muscle contracts it will cause zonule fibers to slack->lens thickens; also ciliary body secretes aqueous humor for the eye

Question 16

Iris

Answer 16

adjustable diaphragm that controls the amount of light that passes through the pupil; contains two muscles: sphincter pupillae m. (when it contracts it will make pupil smaller) and dilator pupillae m. (when it contracts it will make pupil wider).

Question 17

Lacrimal gland

Answer 17

located in the arch of eyebrow and the duct drains into the superior fornix

Question 18

Tear path

Answer 18

lacrimal lake–>lacrimal punctum–>lacrimal sac

when tears enter lacrimal sac they will drain down nasolacrimal duct and into inferior nasal meatus which explains why when you cry, you get the runny nose

Question 19

Levator Palpebrae Superioris

Answer 19

Innervated by CN 3

raises upper eyelid

Question 20

Medial rectus

Answer 20

innervated by CN 3

adducts eyeball

Question 21

Lateral rectus

Answer 21

innervated by CN 6

abdcuts eyeball

Question 22

Superior rectus

Answer 22

innervatd by CN 3

elevates, adducts, intorts eyeball

Question 23

Inferior rectus

Answer 23

innervated by CN 3

depresses, adducts, and extorts eyeball

Question 24

Superior oblique

Answer 24

innervated by CN 4

depresses, abducts, intorts

Question 25

Inferior oblique

Answer 25

innervated by CN 3

elevates, abducts, extorts

Question 26

If injury to sympathetic fibers..?

Answer 26

ptosis (drooping eyelids)
miosis (pupil constriction)
anhidrosis (lack of sweating)

All of these are symptoms of Horner’s Syndrome

Question 27

If injury to parasympathetic fibers with CN 3…?

Answer 27

pupil dilation

loss of accommodation to light reflex

Question 28

What provides somatic sensory info?

Answer 28

CN 5 V1

“I got something in my eye”