Lecture11: Eye And Cranial Nerves

Question 1

What makes up the floor of the Boney Orbit?

Answer 1

Maxilla and Zygomatic

Question 2

What makes up the roof of the Boney Orbit?

Answer 2

The lesser wing of sphenoid, and orbital plate of frontal bone

Question 3

What makes up the Medial Wall of the Boney Orbit?

Answer 3

The Frontal process of maxilla, Lacrimal Bone, and Orbital plate of Ethmoid bone

Question 4

What makes up the medial wall of the Boney Orbit?

Answer 4

The Greater wing of sphenoid and zygomatic bone

Question 5

What does the Outer Fibrous Coat contain?

Answer 5

The Sclera and Cornea

Question 6

What is the function of the conjunctiva?

Answer 6

The formation of the conjunctival sac

Question 7

What does the Vascular Body contain?

Answer 7

Choroid, ciliary body and iris

Question 8

What is the function of the choroid?

Answer 8

The absorption of light that may scatter

Question 9

What is the function of the ciliary body?

Answer 9

Production of aqueous humour by the ciliary processes, the muscle controls the shape of the lens

Question 10

What is the Function of the Sphincter Papillae in the iris?

Answer 10

Circular fibres to constrict the pupil, has Para Sympathetic supply

Question 11

What is the Function of the Dilator Papillae and it’s supply?

Answer 11

Widening of Pupil, Sympathetic supply

Question 12

What is the Function of the Outer Pigmented layer of the Nervous coat

Answer 12

Prevention of scattering of light

Question 13

What is the Outer Pigmented Layer a source of?

Answer 13

Vitamin A

Question 14

What does the Inner neural layer of the Nervous Coat contain?

Answer 14

Photoreceptors

Question 15

Explain Glaucoma

Answer 15

An increase in Aqeuous humor and Intraoccular pressure due to Schlemm canal blockage

Question 16

What are the Symptoms of Glaucoma?

Answer 16

Headache, Pain, redness in the eye and Blurred vision

Question 17

Which segment is concerned with focusing of light?

Answer 17

Anterior Segment

Question 18

What is the segment where light is converted into impulses in the optic nerve?

Answer 18

Posterior Segment

Question 19

What is the Posterior Segment filled with?

Answer 19

Vitreous humor

Question 20

What is the origin of the 4 rectus muscles?

Answer 20

Tendinous Canal

Question 21

What is the function and nerve supply of the Superior Rectus?

Answer 21

Elevation and Adduction, Occulomotor nerve

Question 22

What is the function and nerve supply of the Inferior Rectus?

Answer 22

Depression and Adduction, Occulomotor nerve

Question 23

What is the function and nerve supply of the Medial Rectus?

Answer 23

Adduction, Occulomotor nerve

Question 24

What is the function and nerve supply of the Lateral Rectus?

Answer 24

Abduction, Abducent nerve

Question 25

What is the Superior Oblique origin, nerve supply and function

Answer 25

Roof of orbit, Trochlear nerve, Depression and Abduction

Question 26

What is the origin, nerve supply and function of the Inferior Oblique?

Answer 26

Floor of orbit, Occulomotor nerve, Elevation and Abduction

Question 27

What is the origin of the Lower Palpebrae Superioris?

Answer 27

Roof of Orbit

Question 28

What is the insertion of the Lower Palpebrae Superioris?

Answer 28

Upper eyelid

Question 29

What is the nerve supply of the Lower Palpebrae Superioris?

Answer 29

Mullers’ Muscle

Question 30

What is the action of the Lower Palpebrae Superioris?

Answer 30

Elevation of upper eyelid

Question 31

What is the Occulomotor nerve origin and course?

Answer 31

Midbrain by 2 nuclei, through the lateral wall of the cavernous sinus, then superior orbital fissure

Question 32

What is the origin and course of the Trochlear nerve?

Answer 32

The Trochlear nuclei, through the lateral wall of cavernous then through the superior orbital fissure

Question 33

What is the branch of the Trochlear nerve?

Answer 33

The Superior Oblique muscle

Question 34

What is the origin and course of the Abducent nerve?

Answer 34

The Abducent nucleus in pons, inside cavernous sinus then through the superior orbital fissure

Question 35

What is a branch of the Abducent nerve?

Answer 35

The lateral Rectus

Question 36

What happens if the Occulomotor nerve is injured?

Answer 36

Dilated pupil and downward lateral direction

Question 37

What happens if Trochlear nerve is injured?

Answer 37

Eye turns upward medially with diplopia

Question 38

What happens if Abducent nerve is injured?

Answer 38

Eye is addicted with diplopia