T5: Orbit and the Eye

Question 1

After in a vicious fight with a bloodthirsty mongoose, a man suffers a bite to his cheek, resulting in permenent scaring of his beautiful face. Angered, the man goes on a hulk like rampage; his heart rate increases, eyes dilate, and goes flaccid. Which of the following nerves is responsible for carrying post ganglionic PARAsympathetic fibers to the eye, resulting in pupil constriction after this mans rampage?

A) Long Ciliary nerve
B) Supraorbital nerve
C) Short Ciliary nerve
D) Nasociliary nerve
E) Zygomatic Communicating nerve

FA

Answer 1

C) The Short Ciliary nerve comes off the ciliary ganglion, in which the soma of post ganglionic parasympathetic cells are located. the ciliary ganglion receives fibers mainly from the ocular motor nerve, which contributes the parasympathetic innervation of the ciliary and pupillary constrictor muscles.

Question 2

What are the contents of the inferior orbital fissure?

Answer 2

v2, zygomatic nerve, inf opthalmic vein, infraorbits artery and vein

Question 3

The outer and inner cup give rise to what layers of the retina?

Answer 3

Outer- pigment layer

inner- neural layer

Question 4

The retinal and the sphincter pupils have which embryological origin?

Answer 4

Neuroectoderm

Question 5

the sclera and virtuous body have which embryological origin?

Answer 5

mesoderm

Question 6

the lens has which embryological origin?

Answer 6

surface ectoderm

Question 7

The proximal hyaloid gives rise to?

Answer 7

the central artery and vein

Question 8

Where does the liquoid in eye drain into?

Answer 8

the iridosccleral angle

Question 9

ptosis is failure of which muscle?

Answer 9

superior tarsal of Müller (sympathetic)

Question 10

Where will Vitreous humor be found in the eye?

A. Posterior Chamber
B. Anterior Chamber
C. Postremal Chamber
D. Retina

RFA

Answer 10

Ans. C Postremal= where vitreous humor will be found

A & B= where aqueous humor will be found

D. Retina= is solid part of teh eye no fluid should be found in it.

Question 11

Which artery supplies the pigmented layer of the retina?

A. Central artery of retina
B. Ethmoidal Artery 
C. Posterior Ciliary Artery 
D. Lacrimal Artery
E. Supraorbital Artery 

RFA

Answer 11

Ans. C Posterior Ciliary Artery

A. Central Art. of Retina= Enters Optic Nerve and visual layer of the retina

B. Ethmoidal Art.= Nasal Cavity & Paranasal Sinuses

D. Lacrimal Artery= lacrimal gland

E. Supraorbital Artery= Anterior Scalp

Question 12

A 5 year old girl comes in your clinic with “keyhole pupils” what is the cause of this appearance?

A. Result of a blow on the eye
B. Failure of the rim of the optic cup to develop
C. Failure of the Optic Stalk to Develop
D. Incomplete closure of the retinal fissure
E. Use of teratogenic agents during pregnancy

RFA

Answer 12

Ans D.

A. Would cause detach retina

B. Would result in the iris failing to form

C. Would result in CNII not forming

E. Would cause cataracts