Eye, and orbit

Question 1

Name the bones of the ORBITAL MARGIN

Answer 1

Superior: Frontal
Lateral: Zygomatic
Medial: 
    Anterior: Frontal bone, Frontal process of maxilla
    Posterior: lacrimal bone
Inferior: Zygomatic, and maxilla

Question 2

Name the bones of the ORBITAL CAVITY

Answer 2

Roof – Frontal bone
Floor – Maxilla

Medial wall – Maxillary, Lacrimal, Ethmoid
(lamina papricia), Sphenoid (lesser wing)

Lateral wall – Zygomatic, Sphenoid (greater wing)

Question 3

Orbicularis oculi – orbital and palpebral part

innervation and action

Answer 3

CN: VII

Close eyes

Question 4

Levator palpebrae superioris

innervation and action

Answer 4

N: CN III
A: opens upper eyelid Superior tarsal muscle – (smooth muscle portion under sympathetic control)

Question 5

Sphincter pupillae action and innervation

Answer 5

parasympathetic control, CN III

Question 6

Dilator pupillae – (sympathetic control)

Answer 6

sympathetic control

Question 7

Contraction of ciliary muscle makes the lens

Answer 7

rounder

Question 8

Relaxation of the ciliary muscle makes the lens

Answer 8

flatter

Question 9

All eye muscles are innervated by the oculomotor nerve CN III, EXCEPT….

Answer 9

the superior oblique (trochlear nerve CN IV) and lateral

rectus, (abducens nerve CN VI) … SO4 (LR6)3

Question 10

CN III branches into

two division: What are they?

Answer 10

Superior division – superior rectus, levator palpebrae superioris
Inferior division – Medial rectus, inferior rectus, inferior oblique

Question 11

V1 branches into sensory nerves in the orbit. Describe these branches

Answer 11

Lacrimal nerve – lateral upper eyelid, lacrimal gland and some conjunctiva

Frontal nerve

Nasociliary nerve

Question 12

What are the branches of V1 frontal nerve in the orbit?

Answer 12

Supraorbital nerve – upper eyelid, forehead and scalp Supratrochlear nerve – upper eyelid, forehead and scalp

Question 13

What are the branches of V1 Nasociliary nerve in the orbit?

Answer 13

Long cilliary nerves - eyeball Posterior ethmoidal nerve – sphenoid sinus, ethmoid air cells and nasal cavity

Anterior ethmoidal nerve – ethmoid air cells and nasal cavity
External nasal branches – bridge of nose

Infratrochlear nerve – medial upper eyelid and lacrimal sac

Question 14

Maxillary division V2 in the orbit and innervation

Answer 14

Inferior palpebral nerve – lower eyelid, eyeball

Question 15

STRUCTURES THAT NEED PARASYMPATHETIC INNERVATION:

Answer 15

Oculomotor (III) via ciliary ganglion innervate ciliary muscles and constrictor pupillae muscles

Lacrimal gland - Facial (VII) via deep petrosal nerve (sympathetic fibers)

Question 16

Absent ipsilateral with normal contralateral response:

Answer 16

Normal V with abnormal ipsilateral VII

Question 17

Absent bilateral response:

Answer 17

V abnormality OR bilateral VII abnormality.

Question 18

Absent contralateral response:

Answer 18

Abnormal contralateral VII.

Question 19

Function of Superior tarsal muscle –

Answer 19

sympathetic smooth muscle that maintains sympathetic tone keeping eyes open.