THE ORBIT (normal anatomy)

Question 1

It is represented as a pyramid having four walls converging posteriorly

Answer 1

Orbital Cavity

Question 2

Medial walls of the right and left orbit are parallel and is separated by

Answer 2

Nose

Question 3

What is the angle formed by each of the orbits lateral and medial walls?

Answer 3

45 Degree

Question 4

What is the resulting angle between the two lateral walls of the orbits?

Answer 4

Right Angle

Question 5

What sturdy bony aperture do the parts of the frontal bone, zygomatic (malar) bone, and maxilla formed?

Answer 5

Circular

Question 6

This is slightly smaller in cross-sectional dimension providing protection to the globe

Answer 6

Circular Bony Aperture

Question 7

Approximate volume of the adult’s orbit?

Answer 7

30 mL

Question 8

With the adult’s orbit volume, how many does the eyeball occupies?

Answer 8

One-fifth of the space

Question 9

It is the anterior limit of the orbital cavity which acts as a barrier between lid and orbit

Answer 9

Orbital Septum

Question 10

Where does the orbit relate?

Answer 10

Paranasal SInuses

Question 11

Known as the paper-thin medial wall

Answer 11

Lamina Papyracea

Question 12

What happens when there is direct trauma to the globe?

Answer 12

• thin orbital floor and paper-thin medial wall is easily damaged
• Results in a “blowout fracture” with herniation of orbital contents

Question 13

What happens to the globe when there are defects in the roof like neurofibromatosis?

Answer 13

Visible Pulsations (transmitted from the brain)