Anatomy of the Pituitary gland

Question 1

What is located infreriorly and posteriorly to the cerebrum

Answer 1

Cerebellum

Question 2

The brain stem can be subdivided into what 3 parts?

Answer 2

Midbrain
pons
medulla (oblongata)

Question 3

what is the diencephalon composed of

Answer 3

The thalamus and hypothalamus

Question 4

what does the diencephalon form

Answer 4

The central core of the cerebrum with connections to the right and left cerebral hemispheres and the midbrain

Question 5

What connects the hypothalamus to the pituitary gland

Answer 5

the infundibulum

Question 6

What does an infundibulum mean? regardless of location in the body

Answer 6

A funnel

Question 7

what is the pituitary gland divided into

Answer 7

Anterior and posterior pituitary gland

Question 8

what are the names of the 3 fossae of the skull?

Answer 8

anterior, middle and posterior

Question 9

What are the bounderies of the anterior fossae of the skull

Answer 9

Frontal bone and the lesser wing of the sphenoid bone

Question 10

What are the boundaries of the middle fossae of the skull

Answer 10

Lesser wings of the sphenoid and by the peatrus parts fo the temporal bone

Question 11

What are the boundaries of the posterior fossae of the skull

Answer 11

Peatrus parts of the temporal bone and the occipital bone

Question 12

Where is the pituitary fossa located

Answer 12

In the middle part of the middle fossa (sphenoid bone)

Question 13

what does the pituitary fossa lie within

Answer 13

The sella turcica

Question 14

what structure lies immediately inferior to the pituitary gland

Answer 14

optic chiasm

Question 15

What forms the optic chiasm

Answer 15

Right and left optic nerves (CNs II)

Question 16

What passes posteriorly from the chiasm

Answer 16

The optic tracts

Question 17

Where do the neurones from the optic tract synapse

Answer 17

The thalamus

Question 18

Neurones pass from the thalamus to where

Answer 18

To the visual cortext in the occipital lobe via the optic radiation

Question 19

What can the field of view be divided into

Answer 19

The nasal and temporal side of visual field

Question 20

If the light passes from the nassal side, where will it be perceived

Answer 20

In the temporal retina

Question 21

Describe the route of neurones and action potentials if light passes from the nasal side

Answer 21

light is received by the temrporal retina,
APs are then sent via neurones from the retina long the optic nerve to then pass along the right optic tract to synapse in the thalamus.
A second neurone will then send signals to the visual cortex in the occipital bone

Question 22

Describe the route of neurones and action potentials if light passes from the temporal side

Answer 22

Light rays will be received by the nasal retina and action potentials are sent along to the optic chiasma but will then cross over ehere to pass down the controlateral side in the optic tract to synapse in the thalamus. A second neurone will then send signals to the visual cortex in the occipital bone

Question 23

What happens if there is a pituitary gland tumour

Answer 23

The gland enlarges resulting in compression of the optic chiasma meaning there will be a disruption of visual pathway and the loss of temporal vision

Question 24

Why is there a loss of temporal vision with a pituitary tumour

Answer 24

The tumour disrupts the transmission of action potentials from the nasal retina bilaterally

Question 25

Define bitemporal hemianopia

Answer 25

The loss of temporal field vision in both eyes

Question 26

What are the two types of surgical approach to accessing the pituitary gland

Answer 26

``` Transcranial approach (sub frontal - under the frontal lobe) Transsphenoidal approach (via nasal cavities and sphenoid sinus) ```

Question 27

What forms the roof of the nasal cavity

Answer 27

The cribriform plate of the ethmoid bone

Question 28

What forms the inferior part of the nasal septum

Answer 28

The vomer bone

Question 29

What forms the superior part of the nasal septum

Answer 29

The perpendicular plate of the ethmoid bone

Question 30

The superior and middle nasal concha are part of what?

Answer 30

Ethmoid bone

Question 31

What are paranasal sinuses

Answer 31

Air-filled spaces within the bones surrounding the nasal cavities

Question 32

Where are the 4 paranasal sinuses

Answer 32

``` Frontal bone (frontal sinuses Maxillae (maxillary sinuses) Ethmoid bone (ethmoidal air cells) Sphenoid bone (sphenoid sinuses) ```

Question 33

What are the paranasal sinuses lined by

Answer 33

Mucous secreting respiratory muscosa

Question 34

What are the functions of the paranasal sinuses

Answer 34

To make mucous and drain it into the nasal cavities through ostia _bony drainage holes) Reduces the weight of the skull Add resonance to the voice (maxillary sinuses) Increase buoyancy in aquatic mammals e.g. dolphins

Question 35

What does the transsphenoidal transnasal approach require

Answer 35

Surgical fracture of the nasal septum and the floor and roof of the sphenoid sinus(es)

Question 36

What is another name given to the maxillary sinuses

Answer 36

Antra of the maxilla

Question 37

How many sinuses are located in the ethmoid bone

Answer 37

3 groups - superior, middle and inferior

Question 38

Where are the sphenoid sinuses located

Answer 38

Within the body of the sphenoid bone

Question 39

What type of Le fort fracture can be induced by the surgeon and why

Answer 39

Type 1 - if the surgeon requires better access into the nasal cavity

Question 40

Describe a Type 1 Le Fort fracture

Answer 40

Horizontally along the maxilla

Question 41

Describe a Type 2 Le Fort Fracture

Answer 41

Dissociation from the entire maxilla from the rest of the face

Question 42

Describe a Type 3 Le Fort Fracture

Answer 42

Separation of the facial skeleton form the neurocranium

Question 43

What artery crosses the anterior surface of the pons

Answer 43

The basilar artery

Question 44

What is the posterior extension of the optic nerve

Answer 44

The optic chiasma

Question 45

What is the tantrum cerebelli

Answer 45

A tough sheet of dura mater "tenting" over the cerebellum within the posterior cranial fossa but with a central gap to permit the brainstem to pass through

Question 46

What is the function of the dura mater

Answer 46

A protective lining for the brain

Question 47

What artery lies very close to the pituitary gland

Answer 47

Internal carotid artery

Question 48

What is the diaphragm sell

Answer 48

A tough sheet of dura mater forming a roof (diaphragm) over the pituitary fossa

Question 49

What lies inferior to the diaphragm sella

Answer 49

The pituitary gland

Question 50

The entire cranial cavity is lines internally with dura mater. True or False

Answer 50

True

Question 51

What are the dural venous sinuses

Answer 51

Areas within the cranial cavity where the 2 layers of dura have separated responsible for draining venous blood from the cranial cavity into the internal jugular veins

Question 52

What is the pituitary gland surrounded by

Answer 52

The cavernous and inter cavernous sinuses

Question 53

What arteries pass through the cavernous sinuses

Answer 53

The internal carotid arteries

Question 54

What cranial nerves also run through the cavernous sinus

Answer 54

2,3,4,5i, 5ii, 6

Question 55

The ophthalmic artery is a branch of what artery

Answer 55

The internal carotid artery

Question 56

Where does the ophthalmic artery enter the orbit

Answer 56

Via the optic canal

Question 57

Describe the route of the right internal carotid artery

Answer 57

Passes medially into the cavernous sinus and forms a loop to go and supply the brain

Question 58

What are the 8 structures at risk in pituitary gland surgery

Answer 58

``` Optic chiasm Oculomotor nerve (1) Trochlear nerve (4) Trigeminal nerve (5) Abducent Nerve (6) Cavernous sinus Internal carotid artery Dura mater ```

Question 59

What is the functional deficit of a damaged internal carotid artery

Answer 59

Catastrophic haemmorrhage

Question 60

What is the functional deficit of a damaged dura mater

Answer 60

CSF leak

Question 61

What is the functional deficit of a damaged cavernous sinus

Answer 61

Venous haemorrhage

Question 62

What can cause problems with specific eye movements

Answer 62

Damage to the trochlear nerve, the oculomotor nerve or the abducent nerve

Question 63

What can cause a dilated pupil

Answer 63

A damaged oculomotornerve

Question 64

What can cause sensory symptoms on the face or difficulty chewing

Answer 64

Damage to the trigeminal nerve