optics lecture

Question 1

what innervates the levator palpebrae muscle (LPS)

Answer 1

GSE fibers of the oculomotor nerve (III)

Question 2

what causes complete ptosis?

Answer 2

destruction of the oculomotor nerve or one of its branches to the levator palpebrae superioris muscle.

Question 3

what innervates the small tarsal muscle of muller (smooth muscle)

Answer 3

innervated by post ganglionic sympathetic fibers. preganglionic fibers originated at the level of T1

Question 4

what is Horner’s syndrome?

Answer 4

usually involves the paralysis of the tarsal muscle and concomitant slight ptosis and miosis (pupillary constriction due to paralysis of the dilator pupillae muscle) enophthalmos (sinking of the eye due to paralysis of the orbitalis muscle of muller- slight protrusion effect) and anhydrosis and blushing of the face.

Question 5

what comprises the palpebral fascia?

Answer 5

tarsus and orbital septum of upper and lower lids; continuous with the face and scalp and the deep zone of the eyelid, which is continuous to the orbital cavity

Question 6

describe tarsal/ Meibomian glands

Answer 6

about 30 types, modified sebaceous, located posterior to tarsal plates, deep to palpebral conjunctiva (look like yellow streaks), oily secretions help to resist the overflow of tears at the palpebral margin.

Question 7

describe the orbital septum

Answer 7

continuous with the periosteum

Question 8

what pierces the superior palpebral fascia?

Answer 8

levator palpebrae superioris muscle

Question 9

the bulbar conjunctiva is a thin transpaent membrane which is loosely attached to the eyeball, except at the ..

Answer 9

corneal margin

Question 10

where is the location of the lacrimal gland?

Answer 10

most of the gland is on top of the lateral rectus muscle and LPS, but some protrudes to the upper eyelid

Question 11

where does the lacrimal gland drain?

Answer 11

has 6-10 ducts that drain at the apex of the superior fornix, these tears keep the surface of the cornea moist.

Question 12

where are the presynaptic cell bodies of the parasympathetic innervation of the lacrimal gland located?

Answer 12

superior salivatory nucleus

Question 13

where are the presynaptic cell bodies of the sympathetic innervation of the lacrimal gland located?

Answer 13

superior cervical ganglion

Question 14

what gives rise to the deep petrosal nerve?

Answer 14

internal carotid plexus

Question 15

what gives rise to the greater petrosal nerve?

Answer 15

facial VII

Question 16

what gives rise to the vidian nerve/ Nerve to the pterygoid canal?

Answer 16

deep and greater petrosal nerves