Lab 1

Question 1

Bones of the orbital floor

Answer 1

orbital plate of the frontal bone; lesser wing of sphenoid (near orbital apex)

Question 2

Bones of the medial wall of orbit

Answer 2

orbital plate of ethmoid bone, the body of the sphenoid, lacrimal bone, frontal process of the maxilla.

Question 3

Bones of the floor of the orbit

Answer 3

orbital plate of the maxilla bone, orbital plate of the zygomatic, orbital part of palatine

Question 4

Where are the two lacrimal fossae (for the lacrimal gland and sac) located?

Answer 4

depressed area between the anterior and posterior lacrimal crests in the medial wall of the orbit

Question 5

What bones make up the orbital margin?

Answer 5

frontal and zygomatic

Question 6

What structures are located at the orbital apex?

Answer 6

orbital apex is the area between the orbit and intracranial space that houses structures like the optic canal (OC), superior orbital fissure (SOF), and inferior orbital fissure (IOF), forming an opening to the orbit

Question 7

Between which two walls do you find the “superior orbital fissure”?

Answer 7

the lateral wall and roof of orbit

Question 8

Between which two walls do you find the “inferior orbital fissure”?

Answer 8

between the lateral wall and the floor

Question 9

What major structures pass through the inferior orbital fissure?

Answer 9

inferior ophthalmic vein (not always), infraorbital nerve, infraorbital artery, infraorbital vein, zygomatic nerve, and parasympathetic fibers from pterygopalatine ganglion.

Question 10

What major structures pass through the superior orbital fissure?

Answer 10

-Passing through SOF superior to the common tendinous ring (annulus of Zinn) are: Lacrimal, frontal, and trochlear nerves; superior ophthalmic vein, and
sometimes recurrent meningeal (lacrimal) artery

-Passing through SOF and annulus of Zinn are:
Superior division of oculomotor nerve, nasociliary branch of ophthalmic
nerve, inferior division of oculomotor nerve, and abducens nerve

Question 11

Where is the “trochlea” located?

Answer 11

Located on anterior-medial part of frontal bone

Question 12

What is its purpose of the trochlea?

Answer 12

cartilaginous pulley of the superior oblique muscle.

Question 13

Which is the thickest wall of the orbit?

Answer 13

lateral

Question 14

Which is the thinnest wall of the orbit?

Answer 14

medial

Question 15

Which is the weakest wall of the orbit?

Answer 15

floor

Question 16

Explain the course of the infraorbital nerve.

Answer 16

The infraorbital nerve courses forward, first through the infraorbital groove, and then through the infraorbital canal on the floor of the orbit. It finally emerges on the face through the infraorbital foramen, located near the inferior margin of orbit

Question 17

Refers to the orbital landmark where the Lockwood ligament attaches:

Answer 17

Lateral orbital tubercle (of Whitnall’s)

Question 18

What is label #3 on this picture of the orbit?

Answer 18

superior orbital fissure