A3- anatomy basics

Question 1

List bones that contribute to the 4 walls of the orbital cavity

Answer 1

Superior wall: frontal and sphenoid
Inferior wall: zygomatic, maxilla, palatine
Medial wall: sphenoid, lacrimal, ethmoid, maxilla
Lateral wall: zygomatic, sphenoid

Question 2

Where does the lateral palpebral ligament attach?

Answer 2

From zygomatic bone to superior and inferior tarsus

Question 3

Where does the medial palpebral ligament attach?

Answer 3

From maxilla to superior and inferior tarsus

Question 4

What is the flow of fluid through the lacrimal system?

Answer 4

1: Lacrimal gland secretes fluid continually
2: Moved across surface of eyes as eyelids blink
3: Accumulates medially in lacrimla lake
4: Fluid passes into lacrimal punctum (opening)
5: Drained by superior and inferior lacrimal canaliculi
6: Forms the common lacrimal canaliculi
7: Drains into lacrimal sac
8: Drains into nasolacrimal duct
9: Empties into the inferior meatus of the nasal cavity

Question 5

What is the attachment of the rectus muscles?

Answer 5

All originate at the common tendinous ring
All insert onto the sclera, posterior to the cornea-sclera junction (i.e. SR - to superior sclera, LR - lateral sclera etc.)

Question 6

Where does the superior oblique attach?

Answer 6

O: body of sphenoid
I: Sclera deep to SR, but goes via the trochlear so changes direction

Question 7

Where does the inferior oblique attach?

Answer 7

O: Anterior floor of orbit
I: Sclera deep to LR

Question 8

Where does levator palpebral superioris attach?

Answer 8

O: Lesser wing of sphenoid
I: superior tarsus

Question 9

What bones make up the external nose?

Answer 9

Frontal process of the maxilla
Frontal bones
Nasal bones

Question 10

What makes up the nasal septum?

Answer 10

Anteriorly= septal nasal cartilage
Posteirorly= vomer and perpendicular plate of ethmoid

Question 11

What bones contribute to the nasal cavity?

Answer 11

Nasal
Maxilla
Sphenoid
Vomer
Palatine
Lacrimal
Ethmoid
(“Nerdy Medical Students are often Very PaLE)

Question 12

Describe the position of the meatus in the nasal cavity

Answer 12

Spheno-ethmoidal meatus
Superior concha
Superior nasal meatus
Middle concha
Middle nasal meatus
Inferior concha
Inferior nasal meatus

Question 13

What opens up into each of the meatus?

Answer 13

Spheno-ethmoidal recess: sphenoid sinus
Superior meatus: posterior ethmoid sinus
Middle meatus: frontal sinus, maxillary sinus, anterior and middle ethmoid sinus
Inferior meatus: nasolacrimal duct

Question 14

Where is the sphenoid sinus found?

Answer 14

Within the body of the sphenoid

Question 15

Which sinus is the largest?

Answer 15

Maxillary

Question 16

What bones form the orbital rim?

Answer 16

Superiorly: by frontal bone
Medially: by frontal process of maxilla
Inferiorly: by zygomatic process of maxilla and zygomatic bone
Laterally: by zygomatic bone and zygomatic process of frontal bone

Question 17

What passes through the optic foramen/ canal?

Answer 17

Optic nerve
Ohpthlamic artery

Question 18

What passes through the infra-orbital foramen?

Answer 18

Infra-orbital nerve (branch of maxillary)

Question 19

What passes through the inferior orbital fissure?

Answer 19

Maxillary nerve and infraorbital vessels

Question 20

What passes through the superior orbital fissure?

Answer 20

Oculomotor, trochlear, abducens, ophthlamic (V1)
Superior ophthalmic vein

Question 21

What sinus can be used to access the pituitary gland?

Answer 21

Sphenoid

Question 22

What is the hiatus semilunaris?

Answer 22

Crescent shaped groove in the middle meatus where the frontal, maxillary and ethmoid (anterior and middle) sinuses empty

Question 22

What is the hiatus semilunaris?

Answer 22

Crescent shaped groove in the middle meatus where the frontal, maxillary and ethmoid (anterior and middle) sinuses empty