Anatomy: Pituitary

Question 1

What is the function of the diencephalon?

Answer 1

Forms the central core of the cerebrum with the connections to the right and left cerebral hemisphere and the midbrain

Question 2

What makes up the diencephalon?

Answer 2

The thalamus and the hypothalamus

Question 3

What are the three parts of the midbrain (starting from the most superior)?

Answer 3

Midbrain
Pons
Medulla (oblongata)

Question 4

Where is the pituitary gland

Answer 4

It is a midline structure situated in the pituitary fossa of the sphenoid bone.
Connected to the hypothalamus by a stalk.

Question 5

What is the name of the pituitary stalk

Answer 5

Infundibulum

Question 6

How is the pituitary gland divided anatomically and functionally?

Answer 6

Into anterior pituitary and posterior pituitary

Question 7

Where does the pituitary fossa lie within

Answer 7

the sella turcica

Question 8

Where does the pituitary gland lie in relation to the optic chiasm

Answer 8

Immediately inferior

Question 9

What is the optic chiasm

Answer 9

Formed from the crossing over of the right and left optic nerves.

Question 10

What are the optic nerves called after the optic chiasm

Answer 10

the optic tracts (right and left)

Question 11

What is the name of the optic tracts after they have synapsed at the thalamus

Answer 11

The optic radiation

Question 12

Where do the axons travelling through the optic radiation go to

Answer 12

the visual cortex

Question 13

Where is the visual cortex

Answer 13

the occipital lobe of the brain

Question 14

Where is the optic canal

Answer 14

the sphenoid bone

Question 15

Where do images from the nasal side of the visual field reach the retina

Answer 15

the temporal side

Question 16

Where do images from the temporal side of the visual fiel reach the retina

Answer 16

the nasal side of the retina

Question 17

What affect on vision would a pituitary tumour pressing on the optic chiasm have?

Answer 17

Bitemporal hemianopia (loss of vision in the temporal fields)

Question 18

Why is vision lost in only the temporal fields when the optic chiasm is compressed.1

Answer 18

Images from the temporal field of vision are formed on the nasal retinae. If the optic chiasm is disrupted only APs from the nasal retina are disrupted and so the patient can no longer see what is in the temporal side of their vision.

Question 19

What are the two methods of surgical access to the pituitary fossa.

Answer 19

Transcranial (subfrontal- under the frontal lobe)

Transphenoidal (via the nasal cavities and sphenoid sinus)

Question 20

What type of mucosa lines the paranasal sinuses

Answer 20

Mucous secreting respiratory mucosa

Question 21

Name the paranasal sinuses

Answer 21

Frontal
Maxillary
Ethmoidal air cells
Sphenoid sinuses

Question 22

What is the name of the tissue that is adherent to the bones of the cranial vault

Answer 22

dura mater

Question 23

What is the name given to the dura mater covering the cerebellum

Answer 23

the tentorium cerebelli

Question 24

What is the name of the dura mater covering the roof of the pituitary fossa

Answer 24

The diaphragm sellae

Question 25

What is the function of the dural venous sinuses

Answer 25

Venous channels within the dura marer than drain most of the venous blood from the cranial cavity

Question 26

Where do the dural venous sinuses drain to?

Answer 26

The internal jugular veins

Question 27

Where do the dural venous sinuses drain into the jugular vein

Answer 27

at the jugular foraminae in the floor of the posterior cranial fossa

Question 28

What sinuses surround the pituitary gland

Answer 28

the cavernous and intercavernous sinuses

Question 29

What artery passes through the cavernous sinuses

Answer 29

the internal carotid