Week 4 - Innervation of the Eye & Extraocular Muscles

Question 1

What bones form the orbit?

Answer 1

Roof:
- Frontal Bone
Medial Wall:
- Lacrimal Bone
- Ethmoid Bone
- Palatine Bone
Floor:
- Maxilla
Lateral Wall:
- Zygomatic Bone
- Greater wing of Sphenoid Bone
Apex:
- Lesser wing of Sphenoid Bone

Question 2

Optic Axis visualised

Answer 2

Question 3

What are the connective tissues of the Orbit?

Answer 3

Question 4

What are the 2 parts of the Orbicularis oculi? and what do they do?

Answer 4

• Orbital Part -> shutting eyes tight
• Palpebral Part -> blinking

Question 5

What does the Superior Tarsal muscle do? what nerve innervates it?

Answer 5

helps lift the eyelid

• elevation
• adduction
• medial rotation
• Occulomotor nerve

Question 6

What does the Levator Palpabrae Superiorus do?

Answer 6

Helps lift the eyelid

Question 7

What does the Inferior Tarsal muscle do? what nerve innervates it?

Answer 7

Retracts inferior eyelid -> important when looking down

• depression
• adduction
• lateral rotation
• Occulomotor nerve

Question 8

What is the Common Tendinous Ring & what muscles arise from it?

Answer 8

Rectus muscles

Question 9

Rectus muscles visualised

Answer 9

Question 10

What passes through the Common Tendinous RIng?

Answer 10

• Ophthalmic artery
• Optic nerve
• Occular motor nerve
• Trochlear nerve
• Abducens nerve

Question 11

Movement of muscles in the eye

Answer 11

Question 13

Functions of eye muscles summarised

Answer 13