Orbit, Eyelids and Lacrimal system

Question 1

Superior Orbital Fissure separates:

Answer 1

greater and lesser wings of sphenoid bone

Question 2

SOF transmits

Answer 2

1. CN 3, 4, 6, cranial division of 5
2. sympathetic nerve fibers
3. superior ophthalmic vein

Question 3

Nasolacrimal Canal houses

Answer 3

nasolacrimal duct, which allows tears to drain nasally

Question 4

Nasolacrimal Canal runs from

Answer 4

lacrimal sac to inferior meatus of nose

Question 5

7 layers of eyelid

Answer 5

1. skin and subQ tissue
2. muscles of protraction
3. orbital septum
4. orbital fat
5. muscles of retraction
6. tarsus
7. conjunctiva

Question 6

Muscles of protraction

Answer 6

1. Orbicularis oculi

2. innerv by Cranial Nerve VII

Question 7

Orbital septum

Answer 7

1. Thin multilayered fibrous tissue

2. Protective against infection and trauma

Question 8

upper eyelid, muscles of retraction

Answer 8

1. levator muscle

2. superior tarsal muscle

Question 9

lower eyelid: muscles of retraction

Answer 9

1. inferior tarsal muscle

2. capsulopalpebral fascia

Question 10

tarsus

Answer 10

dense plate of c.t

Question 11

conjunctiva

Answer 11

extends from orbit to cover interior of eyelid

Question 12

Lacrimal canaliculi:

Answer 12

1. Aka ducts

2. Small channels in each eyelid which conduct tears

Question 13

Lacrimal Puncta:

Answer 13

Minute orifices where the lacrimal canaliculi commence

Question 14

Meibomian Glands

Answer 14

1. Specialized sebaceous gland in the eyelid

2. Oily substance prevents rapid tear evaporation

Question 15

lacrimal gland is located

Answer 15

in superior, lateral portion of each orbit

Question 16

lacrimal gland secretes

Answer 16

aqueous portion of tears

Question 17

glands of zeiss

Answer 17

1. specialized sebaceous glands that service the eyelashes

2. located on margin of eyelid

Question 18

Whitnall’s Ligament

Answer 18

1. Support ligament for upper eyelid and superior orbit

2. Improves efficiency of levator

Question 19

Muller Muscle

Answer 19

1. Helps raise upper eyelid

2. Smooth muscle adjoining levator

Question 20

Lockwood’s Ligament

Answer 20

1. Supports eye inferiorly and prevents downward displacement
2. Forms hammock below eyeball

Question 21

Annulus of Zinn:

Answer 21

Ring of fibrous tissue around optic nerve, origin for 5 of the EOM

Question 22

Primary Blood supply eye

Answer 22

ophthalmic artery (branch of internal carotid)

Question 23

Secondary blood supply eye

Answer 23

Secondary supply from facial and maxillary arteries (branch of external carotid)

Question 24

eye: venous drainage

Answer 24

Drained by ophthalmic vein

Anastomoses anteriorly with facial veins and posteriorly with pterygoid plexus

Question 25

List extra-ocular muscles

Answer 25

1. Superior rectus 2. inferior rectus 3. lateral rectus (CN 6) 4. Medial rectus 5. Inferior oblique 6. Superior Oblique (CN 4) rest CN 3