Pituitary Gland Anatomy

Question 1

what makes up the diencephalon?

Answer 1

thalamus and hypothalamus

Question 2

what does the diencephalon form?

Answer 2

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

Question 3

what is the infundibulum?

Answer 3

anatomically and functionally connects the hypothalamus and the pituitary gland

Question 4

what can the infundibulum otherwise be known as?

Answer 4

pituitary stalk, infundibulum=funnel

Question 5

what lobes is the pituitary anatomically and functionally divided up into?

Answer 5

anterior and posterior

Question 6

what is the anterior lobe also known as?

Answer 6

adenohypophysis

• pars distalis
• pars tuberalis
• pars intermedia

Question 7

what is the posterior lobe also known as?

Answer 7

neurohypophysis

-pars nervosa

Question 8

which lobe is an extension of brain?

Answer 8

posterior

Question 9

which lobe synthesises and releases most of the pituitary hormones?

Answer 9

anterior

Question 10

which hormones does the posterior lobe produce?

Answer 10

ADH and oxytocin (synthesised in hypothalamus)

Question 11

what is the location of the pituitary gland?

Answer 11

it is a midline structure in the pituitary fossa of the sphenoid bone (deep in cranial cavity)

Question 12

where does the pituitary fossa lie?

Answer 12

sella turcica

Question 13

what is the relation between the pituitary gland and the optic chiasm?

Answer 13

lies immediately inferior to the optic chiasm

Question 14

what is the brain stem continuous with?

Answer 14

spinal cord

Question 15

what is the controlling centre for the whole endocrine system?

Answer 15

hypothalamus

Question 16

what is the thalamus?

Answer 16

centre for sensation

Question 17

what does sella turcica mean?

Answer 17

turkish saddle

Question 18

what are the visual fields?

Answer 18

nasal and temporal (right and left)

Question 19

what are the photoreceptors in the nasal and temporal retina?

Answer 19

rods and cones

Question 20

what is the optic chiasma formed from?

Answer 20

right and left optic nerves

Question 21

what visual fields cross over?

Answer 21

nasal

Question 22

what clinical feature can a pituitary tumour result in?

Answer 22

bitemporal hemianopia

Question 23

why does bitemporal hemianopia occur?

Answer 23

tumour impinging on optic chiasma which disrupts transmission of action potentials from nasal retina bilaterally

Question 24

what field of vision is restricted in bitemporal hemianopia?

Answer 24

temporal (medial part of retinas)

Question 25

what are the two surgical access areas?

Answer 25

transcranial and transsphenoidal

Question 26

what surgical access type is more common?

Answer 26

transsphenoidal

Question 27

what are nasal conchae covered by?

Answer 27

mucous membranes

Question 28

what do nasal conchae do?

Answer 28

warm air and help to humidify it when breathing through the nose

Question 29

what are paranasal sinuses?

Answer 29

air filled spaces within bones surrounding nasal cavities

Question 30

what are paranasal sinuses lined by?

Answer 30

mucus-secreting respiratory mucosa

Question 31

is there a known function of paranasal sinuses?

Answer 31

no

Question 32

what are some suggested functions of paranasal sinuses?

Answer 32

secrete mucus which drains into nasal cavities through ostia (single=ostium-bony drainage hole), reduce weight of the skull, add resonance to voice

Question 33

what are Le Fort fractures of the facial skeleton?

Answer 33

nasty fractures that depend on how much of the eye or orbital cavity is involved

Question 34

what is significant about Le Fort 1 fractures?

Answer 34

Le Fort 1 down fracture approach to the nasal cavities provides better surgical access in more complicated cases

Question 35

what is dura mater?

Answer 35

thick fibrous membrane that covers the whole brain and lines the entire cranial cavity internally

Question 36

what do the vertebral arteries anastomose to form?

Answer 36

basilar artery

Question 37

what is the tentorium cerebelli?

Answer 37

thought sheet of dura mater tenting over cerebellum in posterior cranial fossa but has a central gap to allow brainstem to pass through

Question 38

what is the diaphragm sellae?

Answer 38

tough sheet of dura mater forming roof over pituitary fossa and sellae turcica

Question 39

what does trigeminal mean?

Answer 39

three twins

Question 40

what are dural venous sinuses?

Answer 40

venous channels within dura mater that drain most of venous blood from cranial cavity including the brain into internal jugular veins (spaces between dural folds

Question 41

what makes dural venous sinuses different to veins?

Answer 41

no proper venous walls (different histologically but similar function

Question 42

where do dural venous sinuses drain into internal jugular veins?

Answer 42

jugular foraminae in the floor of posterior cranial fossa